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b4ff5ca6ae
This patch contains a prototype of a new widget framework. In this framework, Components can be reused in the tree as many times as the author desires. Also, StatefulComponent is split into two pieces, a ComponentConfiguration and a ComponentState. The ComponentConfiguration is created by the author and can be reused as many times as desired. When mounted into the tree, the ComponentConfiguration creates a ComponentState to hold the state for the component. The state remains in the tree and cannot be reused.
1680 lines
57 KiB
Dart
1680 lines
57 KiB
Dart
// Copyright 2015 The Chromium Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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import 'dart:async';
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import 'dart:collection';
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import 'dart:sky' as sky;
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import 'package:sky/animation.dart';
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import 'package:sky/services.dart';
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import 'package:sky/src/rendering/box.dart';
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import 'package:sky/src/rendering/error.dart';
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import 'package:sky/src/rendering/hit_test.dart';
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import 'package:sky/src/rendering/object.dart';
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import 'package:sky/src/rendering/sky_binding.dart';
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import 'package:sky/src/rendering/view.dart';
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export 'package:sky/src/rendering/box.dart' show BoxConstraints, BoxDecoration, Border, BorderSide, EdgeDims;
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export 'package:sky/src/rendering/hit_test.dart' show EventDisposition, combineEventDispositions;
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export 'package:sky/src/rendering/object.dart' show Point, Offset, Size, Rect, Color, Paint, Path;
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final bool _shouldLogRenderDuration = false; // see also 'enableProfilingLoop' argument to runApp()
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typedef Widget Builder();
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typedef void WidgetTreeWalker(Widget widget);
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abstract class Key {
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const Key.constructor(); // so that subclasses can call us, since the Key() factory constructor shadows the implicit constructor
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factory Key(String value) => new ValueKey<String>(value);
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}
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class ValueKey<T> extends Key {
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const ValueKey(this.value) : super.constructor();
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final T value;
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String toString() => '[\'${value}\']';
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bool operator==(other) => other is ValueKey<T> && other.value == value;
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int get hashCode => value.hashCode;
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}
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class ObjectKey extends Key {
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const ObjectKey(this.value) : super.constructor();
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final Object value;
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String toString() => '[${value.runtimeType}(${value.hashCode})]';
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bool operator==(other) => other is ObjectKey && identical(other.value, value);
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int get hashCode => identityHashCode(value);
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}
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typedef void GlobalKeySyncListener(GlobalKey key, Widget widget);
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typedef void GlobalKeyRemoveListener(GlobalKey key);
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abstract class GlobalKey extends Key {
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const GlobalKey.constructor() : super.constructor(); // so that subclasses can call us, since the Key() factory constructor shadows the implicit constructor
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factory GlobalKey({ String label }) => new LabeledGlobalKey(label); // the label is purely for debugging purposes and is otherwise ignored
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static final Map<GlobalKey, Widget> _registry = new Map<GlobalKey, Widget>();
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static final Map<GlobalKey, int> _debugDuplicates = new Map<GlobalKey, int>();
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static final Map<GlobalKey, Set<GlobalKeySyncListener>> _syncListeners = new Map<GlobalKey, Set<GlobalKeySyncListener>>();
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static final Map<GlobalKey, Set<GlobalKeyRemoveListener>> _removeListeners = new Map<GlobalKey, Set<GlobalKeyRemoveListener>>();
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static final Set<GlobalKey> _syncedKeys = new Set<GlobalKey>();
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static final Set<GlobalKey> _removedKeys = new Set<GlobalKey>();
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void _register(Widget widget) {
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assert(() {
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if (_registry.containsKey(this)) {
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int oldCount = _debugDuplicates.putIfAbsent(this, () => 1);
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assert(oldCount >= 1);
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_debugDuplicates[this] = oldCount + 1;
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}
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return true;
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});
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_registry[this] = widget;
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}
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void _unregister(Widget widget) {
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assert(() {
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if (_registry.containsKey(this) && _debugDuplicates.containsKey(this)) {
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int oldCount = _debugDuplicates[this];
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assert(oldCount >= 2);
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if (oldCount == 2) {
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_debugDuplicates.remove(this);
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} else {
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_debugDuplicates[this] = oldCount - 1;
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}
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}
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return true;
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});
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if (_registry[this] == widget) {
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_registry.remove(this);
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_removedKeys.add(this);
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}
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}
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void _didSync() {
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_syncedKeys.add(this);
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}
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static void registerSyncListener(GlobalKey key, GlobalKeySyncListener listener) {
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assert(key != null);
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Set<GlobalKeySyncListener> listeners =
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_syncListeners.putIfAbsent(key, () => new Set<GlobalKeySyncListener>());
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bool added = listeners.add(listener);
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assert(added);
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}
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static void unregisterSyncListener(GlobalKey key, GlobalKeySyncListener listener) {
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assert(key != null);
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assert(_syncListeners.containsKey(key));
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bool removed = _syncListeners[key].remove(listener);
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if (_syncListeners[key].isEmpty)
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_syncListeners.remove(key);
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assert(removed);
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}
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static void registerRemoveListener(GlobalKey key, GlobalKeyRemoveListener listener) {
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assert(key != null);
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Set<GlobalKeyRemoveListener> listeners =
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_removeListeners.putIfAbsent(key, () => new Set<GlobalKeyRemoveListener>());
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bool added = listeners.add(listener);
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assert(added);
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}
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static void unregisterRemoveListener(GlobalKey key, GlobalKeyRemoveListener listener) {
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assert(key != null);
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assert(_removeListeners.containsKey(key));
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bool removed = _removeListeners[key].remove(listener);
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if (_removeListeners[key].isEmpty)
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_removeListeners.remove(key);
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assert(removed);
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}
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static Widget getWidget(GlobalKey key) {
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assert(key != null);
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return _registry[key];
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}
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static void _notifyListeners() {
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assert(!_inBuildDirtyComponents);
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assert(!Widget._notifyingMountStatus);
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assert(() {
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String message = '';
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for (GlobalKey key in _debugDuplicates.keys) {
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message += 'Duplicate GlobalKey found amongst mounted widgets: $key (${_debugDuplicates[key]} instances)\n';
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message += 'Most recently registered instance is:\n${_registry[key]}\n';
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}
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if (!_debugDuplicates.isEmpty)
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throw message;
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return true;
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});
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if (_syncedKeys.isEmpty && _removedKeys.isEmpty)
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return;
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try {
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for (GlobalKey key in _syncedKeys) {
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Widget widget = _registry[key];
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if (widget != null && _syncListeners.containsKey(key)) {
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Set<GlobalKeySyncListener> localListeners = new Set<GlobalKeySyncListener>.from(_syncListeners[key]);
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for (GlobalKeySyncListener listener in localListeners)
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listener(key, widget);
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}
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}
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for (GlobalKey key in _removedKeys) {
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if (!_registry.containsKey(key) && _removeListeners.containsKey(key)) {
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Set<GlobalKeyRemoveListener> localListeners = new Set<GlobalKeyRemoveListener>.from(_removeListeners[key]);
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for (GlobalKeyRemoveListener listener in localListeners)
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listener(key);
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}
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}
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} finally {
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_removedKeys.clear();
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_syncedKeys.clear();
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}
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}
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}
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class LabeledGlobalKey extends GlobalKey {
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// the label is purely for documentary purposes and does not affect the key
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const LabeledGlobalKey(this._label) : super.constructor();
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final String _label;
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String toString() => '[GlobalKey ${_label != null ? _label : hashCode}]';
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}
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class GlobalObjectKey extends GlobalKey {
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const GlobalObjectKey(this.value) : super.constructor();
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final Object value;
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String toString() => '[GlobalKey ${value.runtimeType}(${value.hashCode})]';
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bool operator==(other) => other is GlobalObjectKey && identical(other.value, value);
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int get hashCode => identityHashCode(value);
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}
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/// A base class for elements of the widget tree
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abstract class Widget {
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Widget({ Key key }) : _key = key {
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assert(_isConstructedDuringBuild());
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}
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// TODO(jackson): Remove this workaround for limitation of Dart mixins
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Widget._withKey(Key key) : _key = key {
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assert(_isConstructedDuringBuild());
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}
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// you should not build the UI tree ahead of time, build it only during build()
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bool _isConstructedDuringBuild() => this is AbstractWidgetRoot || this is App || _inBuildDirtyComponents || _inLayoutCallbackBuilder > 0;
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Key _key;
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/// A semantic identifer for this widget
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///
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/// Keys are used to find matches when synchronizing two widget trees, for
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/// example after a [Component] rebuilds. Without keys, two widgets can match
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/// if their runtimeType matches. With keys, the keys must match as well.
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/// Assigning a key to a widget can improve performance by causing the
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/// framework to sync widgets that share a lot of common structure and can
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/// help match stateful components semantically rather than positionally.
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Key get key => _key;
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Widget _parent;
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/// The parent of this widget in the widget tree.
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Widget get parent => _parent;
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// The "generation" of a Widget is the frame in which it was last
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// synced. We use this to tell if an instance of a Widget has moved
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// to earlier in the tree so that when we come across where it used
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// to be, we pretend it was never there. See syncChild().
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static int _currentGeneration = 1;
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int _generation = 0;
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bool get isFromOldGeneration => _generation < _currentGeneration;
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void _markAsFromCurrentGeneration() { _generation = _currentGeneration; }
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bool get _hasState => false;
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static bool _canSync(Widget a, Widget b) {
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assert(a != null);
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assert(b != null);
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return (a == b) ||
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(a.runtimeType == b.runtimeType &&
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a.key == b.key &&
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(!a._hasState || !b._hasState));
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}
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bool _mounted = false;
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bool _wasMounted = false;
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bool get mounted => _mounted;
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static bool _notifyingMountStatus = false;
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static List<Widget> _mountedChanged = new List<Widget>();
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/// Called during the synchronizing process to update the widget's parent.
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void setParent(Widget newParent) {
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assert(!_notifyingMountStatus);
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if (_parent == newParent)
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return;
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_parent = newParent;
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if (newParent == null) {
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if (_mounted) {
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_mounted = false;
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_mountedChanged.add(this);
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}
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} else {
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assert(newParent._mounted);
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if (_parent._mounted != _mounted) {
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_mounted = _parent._mounted;
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_mountedChanged.add(this);
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}
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}
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}
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/// Walks the immediate children of this widget.
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///
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/// Override this if you have children and call walker on each child.
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/// Note that you may be called before the child has had its parent
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/// pointer set to point to you. Your walker, and any methods it
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/// invokes on your descendants, should not rely on the ancestor
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/// chain being correctly configured at this point.
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void walkChildren(WidgetTreeWalker walker) { }
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/// If the object has a single child, return it. Override this if
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/// you define a new child model with only one child.
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Widget get singleChild => null;
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/// Detaches the single child of this object from this object,
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/// without calling remove() on that child.
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/// Only called when singleChild returns a non-null node.
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/// Override this if you override singleChild to return non-null.
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void takeChild() {
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assert(singleChild != null);
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throw '${runtimeType} does not define a "takeChild()" method';
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}
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static void _notifyMountStatusChanged() {
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try {
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sky.tracing.begin('Widget._notifyMountStatusChanged');
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_notifyingMountStatus = true;
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for (Widget node in _mountedChanged) {
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if (node._wasMounted != node._mounted) {
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if (node._mounted)
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node.didMount();
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else
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node.didUnmount();
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node._wasMounted = node._mounted;
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}
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}
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_mountedChanged.clear();
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} finally {
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_notifyingMountStatus = false;
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sky.tracing.end('Widget._notifyMountStatusChanged');
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}
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GlobalKey._notifyListeners();
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}
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/// Override this function to learn when this [Widget] enters the widget tree.
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void didMount() {
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if (key is GlobalKey)
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(key as GlobalKey)._register(this); // TODO(ianh): remove cast when analyzer is cleverer
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}
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/// Override this function to learn when this [Widget] leaves the widget tree.
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void didUnmount() {
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if (key is GlobalKey)
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(key as GlobalKey)._unregister(this); // TODO(ianh): remove cast when analyzer is cleverer
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}
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RenderObject _renderObject;
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/// The underlying [RenderObject] associated with this [Widget].
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RenderObject get renderObject => _renderObject;
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// Subclasses which implements Nodes that become stateful may return true
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// if the node has become stateful and should be retained.
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// This is called immediately before _sync().
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// Component.retainStatefulNodeIfPossible() calls syncConstructorArguments().
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// This is only ever called on a node A with an argument B if _canSync(A, B)
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// is true. It's ok if after calling retainStatefulNodeIfPossible(), the two
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// nodes no longer return true from _canSync().
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bool retainStatefulNodeIfPossible(Widget newNode) => false;
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void _sync(Widget old, dynamic slot) {
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// When this is called, old must be from an old generation. It's a violation
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// of the _sync() contract to call _sync() with an old node that has already
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// been synced this generation, as this means that that node is elsewhere in
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// the tree by now.
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// By the time we get here, though, syncChild() has already been called on
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// our children (by the subclasses overriding this). This means 'old' may
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// have been moved to somewhere else in the tree and might therefore already
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// be from a new generation.
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assert(isFromOldGeneration);
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_markAsFromCurrentGeneration();
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if (old != null && old != this)
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old._markAsFromCurrentGeneration();
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if (key is GlobalKey)
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(key as GlobalKey)._didSync(); // TODO(ianh): Remove the cast once the analyzer is cleverer.
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}
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void updateSlot(dynamic newSlot);
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// 'slot' is the identifier that the ancestor RenderObjectWrapper uses to know
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// where to put this descendant. If you just defer to a child, then make sure
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// to pass them the slot.
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Set<Type> _dependencies;
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Inherited inheritedOfType(Type targetType) {
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if (_dependencies == null)
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_dependencies = new Set<Type>();
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_dependencies.add(targetType);
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Widget ancestor = parent;
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while (ancestor != null && ancestor.runtimeType != targetType)
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ancestor = ancestor.parent;
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return ancestor;
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}
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void dependenciesChanged() {
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// This is called if you've use inheritedOfType and the Inherited
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// ancestor you were provided was changed. For a widget to use Inherited
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// it needs an implementation of dependenciesChanged. If your widget extends
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// Component or RenderObjectWrapper this is provided for you automatically.
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// If you aren't able to extend one of those classes, you need to
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// provide your own implementation of dependenciesChanged.
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assert(false);
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}
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void remove() {
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walkChildren((Widget child) {
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if (child.isFromOldGeneration || !isFromOldGeneration) {
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assert(child.parent == this);
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child.remove();
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} else {
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// if it's from the current generation and we're not, it means it's been moved somewhere else in the tree already and isn't really our child anymore
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assert(child.parent != this);
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}
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});
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_renderObject = null;
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setParent(null);
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}
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void detachRenderObject();
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Widget _getCandidateSingleChildFrom(Widget oldChild) {
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Widget candidate = oldChild.singleChild;
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if (candidate != null && !candidate.isFromOldGeneration)
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candidate = null;
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assert(candidate == null || candidate.parent == oldChild);
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return candidate;
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}
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// Returns the child which should be retained as the child of this node.
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Widget syncChild(Widget newNode, Widget oldNode, dynamic slot) {
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String debugDetails;
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assert(() {
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// we save this information early because by the time the exception fires we might have changed everything around
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debugDetails = ' old child: $oldNode\n new child: $newNode';
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return true;
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});
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try {
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// At this point, oldNode might have been moved to a new part in the tree.
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// If this has happened, it will already have been synced, in which case
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// it will be from a new generation. Our contract with _sync() is that we
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// will not pass an old child that has been moved to elsewhere in the
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// tree, so it's important that we verify at each step here that we're not
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// dealing with such a child. This is why this function keeps checking
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// isFromOldGeneration on the candidate "old" children.
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if (newNode == oldNode) {
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// If our child literally hasn't changed identity, short-circuit the
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// work. That subtree hasn't changed. We still need to set the parent
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// because _we_ might have changed identity, even if the child hasn't.
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assert(newNode is! RenderObjectWrapper ||
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(newNode is RenderObjectWrapper && newNode._ancestor != null)); // if the child didn't change, it had better be configured
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assert(newNode is! StatefulComponent ||
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(newNode is StatefulComponent && newNode._isStateInitialized)); // if the child didn't change, it had better be configured
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// TODO(ianh): Simplify the two asserts above once the analyzer is cleverer
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if (newNode != null) {
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newNode.setParent(this);
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newNode._markAsFromCurrentGeneration();
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}
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return newNode; // Nothing to do. Subtrees must be identical.
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}
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// if the old node isn't the same as the new node and has already been synced, then
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// we must assume that it has been moved elsewhere in the tree and isn't really a
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// match for the node we're trying to insert.
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if (oldNode != null && !oldNode.isFromOldGeneration)
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oldNode = null;
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if (newNode == null) {
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// the child in this slot has gone away
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// remove it if they old one is still here
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if (oldNode != null) {
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assert(oldNode != null);
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assert(oldNode.isFromOldGeneration);
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assert(oldNode.mounted);
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oldNode.detachRenderObject();
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oldNode.remove();
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assert(!oldNode.mounted);
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// we don't update the generation of oldNode, because there's
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// still a chance it could be reused as-is later in the tree.
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}
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return null;
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}
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if (oldNode != null) {
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assert(newNode != null);
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assert(newNode.isFromOldGeneration);
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assert(oldNode.isFromOldGeneration);
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if (!Widget._canSync(newNode, oldNode)) {
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assert(oldNode.mounted);
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// We want to handle the case where there is a removal of zero
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// or more widgets. In this case, we should be able to sync
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// ourselves with a Widget that is a descendant of the
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// oldNode, skipping the nodes in between. Let's try that.
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Widget deadNode = oldNode;
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Widget candidate = _getCandidateSingleChildFrom(oldNode);
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oldNode = null;
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while (candidate != null) {
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if (Widget._canSync(newNode, candidate)) {
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assert(candidate.parent != null);
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assert(candidate.parent.singleChild == candidate);
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if (candidate.renderObject != deadNode.renderObject) {
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// TODO(ianh): Handle removal across RenderNode boundaries
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} else {
|
|
candidate.parent.takeChild();
|
|
oldNode = candidate;
|
|
}
|
|
break;
|
|
}
|
|
candidate = _getCandidateSingleChildFrom(candidate);
|
|
}
|
|
|
|
// TODO(ianh): Handle insertion, too...
|
|
|
|
if (oldNode == null)
|
|
deadNode.detachRenderObject();
|
|
deadNode.remove();
|
|
}
|
|
if (oldNode != null) {
|
|
assert(newNode.isFromOldGeneration);
|
|
assert(oldNode.isFromOldGeneration);
|
|
assert(Widget._canSync(newNode, oldNode));
|
|
if (oldNode == newNode) {
|
|
newNode.setParent(this);
|
|
newNode._markAsFromCurrentGeneration();
|
|
return newNode;
|
|
} else if (oldNode.retainStatefulNodeIfPossible(newNode)) {
|
|
assert(oldNode.mounted);
|
|
assert(!newNode.mounted);
|
|
oldNode.setParent(this);
|
|
oldNode._sync(newNode, slot);
|
|
assert(oldNode.renderObject is RenderObject);
|
|
return oldNode;
|
|
} else {
|
|
oldNode.setParent(null);
|
|
}
|
|
}
|
|
}
|
|
|
|
assert(oldNode == null || (oldNode.mounted == false && oldNode.parent == null && newNode.mounted == false && oldNode.isFromOldGeneration && newNode.isFromOldGeneration));
|
|
assert(oldNode != newNode);
|
|
newNode.setParent(this);
|
|
newNode._sync(oldNode, slot);
|
|
assert(newNode.renderObject is RenderObject);
|
|
return newNode;
|
|
|
|
} catch (e, stack) {
|
|
_debugReportException('syncing children of $this\n$debugDetails', e, stack);
|
|
return null;
|
|
}
|
|
}
|
|
|
|
// This function can be safely called when the layout is valid.
|
|
// For example Listener or SizeObserver callbacks can safely call
|
|
// globalToLocal().
|
|
Point globalToLocal(Point point) {
|
|
assert(mounted);
|
|
assert(renderObject is RenderBox);
|
|
return (renderObject as RenderBox).globalToLocal(point);
|
|
}
|
|
|
|
// See globalToLocal().
|
|
Point localToGlobal(Point point) {
|
|
assert(mounted);
|
|
assert(renderObject is RenderBox);
|
|
return (renderObject as RenderBox).localToGlobal(point);
|
|
}
|
|
|
|
String toString() {
|
|
List<String> details = <String>[];
|
|
debugAddDetails(details);
|
|
String detailString = details.join('; ');
|
|
return '$runtimeType($detailString})';
|
|
}
|
|
void debugAddDetails(List<String> details) {
|
|
if (key != null)
|
|
details.add('$key');
|
|
details.add('hashCode=$hashCode');
|
|
details.add(mounted ? 'mounted' : 'not mounted');
|
|
if (_generation != _currentGeneration) {
|
|
if (_generation == 0) {
|
|
details.add('never synced');
|
|
} else {
|
|
int delta = _generation - _currentGeneration;
|
|
String sign = delta < 0 ? '' : '+';
|
|
details.add('gen$sign$delta');
|
|
}
|
|
}
|
|
}
|
|
String toStringDeep([String prefix = '', String startPrefix = '']) {
|
|
String childrenString = '';
|
|
List<Widget> children = new List<Widget>();
|
|
walkChildren(children.add);
|
|
if (children.length > 0) {
|
|
Widget lastChild = children.removeLast();
|
|
String nextStartPrefix = prefix + ' +-';
|
|
String nextPrefix = prefix + ' | ';
|
|
for (Widget child in children)
|
|
childrenString += child.toStringDeep(nextPrefix, _adjustPrefixWithParentCheck(child, nextStartPrefix));
|
|
nextStartPrefix = prefix + ' \'-';
|
|
nextPrefix = prefix + ' ';
|
|
childrenString += lastChild.toStringDeep(nextPrefix, _adjustPrefixWithParentCheck(lastChild, nextStartPrefix));
|
|
}
|
|
return '$startPrefix$this\n$childrenString';
|
|
}
|
|
String _adjustPrefixWithParentCheck(Widget child, String prefix) {
|
|
if (child.parent == this)
|
|
return prefix;
|
|
if (child.parent == null)
|
|
return '$prefix [[DISCONNECTED]] ';
|
|
return '$prefix [[PARENT IS ${child.parent}]] ';
|
|
}
|
|
}
|
|
|
|
|
|
// Descendants of TagNode provide a way to tag RenderObjectWrapper and
|
|
// Component nodes with annotations, such as event listeners,
|
|
// stylistic information, etc.
|
|
abstract class TagNode extends Widget {
|
|
|
|
TagNode({ Key key, Widget child })
|
|
: child = child, super(key: key) {
|
|
assert(child != null);
|
|
}
|
|
|
|
// TODO(jackson): Remove this workaround for limitation of Dart mixins
|
|
TagNode._withKey(Widget child, Key key)
|
|
: child = child, super._withKey(key);
|
|
|
|
Widget child;
|
|
|
|
void walkChildren(WidgetTreeWalker walker) {
|
|
if (child != null)
|
|
walker(child);
|
|
}
|
|
|
|
Widget get singleChild => child;
|
|
|
|
bool _debugChildTaken = false;
|
|
|
|
void takeChild() {
|
|
assert(!_debugChildTaken);
|
|
assert(singleChild == child);
|
|
assert(child != null);
|
|
child = null;
|
|
_renderObject = null;
|
|
assert(() { _debugChildTaken = true; return true; });
|
|
}
|
|
|
|
void _sync(TagNode old, dynamic slot) {
|
|
assert(!_debugChildTaken);
|
|
child = syncChild(child, old?.child, slot);
|
|
if (child != null) {
|
|
assert(child.parent == this);
|
|
assert(child.renderObject != null);
|
|
_renderObject = child.renderObject;
|
|
assert(_renderObject == renderObject); // in case a subclass reintroduces it
|
|
} else {
|
|
_renderObject = null;
|
|
}
|
|
super._sync(old, slot);
|
|
}
|
|
|
|
void updateSlot(dynamic newSlot) {
|
|
child.updateSlot(newSlot);
|
|
}
|
|
|
|
void detachRenderObject() {
|
|
assert(!_debugChildTaken);
|
|
if (child != null)
|
|
child.detachRenderObject();
|
|
}
|
|
|
|
}
|
|
|
|
abstract class ParentDataNode extends TagNode {
|
|
ParentDataNode({ Key key, Widget child })
|
|
: super(key: key, child: child);
|
|
|
|
/// Subclasses should override this function to ensure that they are placed
|
|
/// inside widgets that expect them.
|
|
///
|
|
/// The given ancestor is the first non-component ancestor of this widget.
|
|
void debugValidateAncestor(Widget ancestor);
|
|
}
|
|
|
|
abstract class Inherited extends TagNode {
|
|
|
|
Inherited({ Key key, Widget child }) : super._withKey(child, key);
|
|
|
|
void _sync(Widget old, dynamic slot) {
|
|
if (old != null) {
|
|
if (syncShouldNotify(old))
|
|
notifyDescendants();
|
|
}
|
|
super._sync(old, slot);
|
|
}
|
|
|
|
void notifyDescendants() {
|
|
final Type ourRuntimeType = runtimeType;
|
|
void notifyChildren(Widget child) {
|
|
if (child._dependencies != null &&
|
|
child._dependencies.contains(ourRuntimeType))
|
|
child.dependenciesChanged();
|
|
if (child.runtimeType != ourRuntimeType)
|
|
child.walkChildren(notifyChildren);
|
|
}
|
|
walkChildren(notifyChildren);
|
|
}
|
|
|
|
bool syncShouldNotify(Inherited old);
|
|
|
|
}
|
|
|
|
typedef EventDisposition GestureEventListener(sky.GestureEvent e);
|
|
typedef EventDisposition PointerEventListener(sky.PointerEvent e);
|
|
typedef EventDisposition EventListener(sky.Event e);
|
|
|
|
class Listener extends TagNode {
|
|
Listener({
|
|
Key key,
|
|
Widget child,
|
|
PointerEventListener this.onPointerDown,
|
|
PointerEventListener this.onPointerMove,
|
|
PointerEventListener this.onPointerUp,
|
|
PointerEventListener this.onPointerCancel
|
|
}) : super(key: key, child: child);
|
|
|
|
final PointerEventListener onPointerDown;
|
|
final PointerEventListener onPointerMove;
|
|
final PointerEventListener onPointerUp;
|
|
final PointerEventListener onPointerCancel;
|
|
|
|
EventDisposition _handleEvent(sky.Event event) {
|
|
if (onPointerDown != null && event.type == 'pointerdown')
|
|
return onPointerDown(event);
|
|
if (onPointerMove != null && event.type == 'pointermove')
|
|
return onPointerMove(event);
|
|
if (onPointerUp != null && event.type == 'pointerup')
|
|
return onPointerUp(event);
|
|
if (onPointerCancel != null && event.type == 'pointercancel')
|
|
return onPointerCancel(event);
|
|
return EventDisposition.ignored;
|
|
}
|
|
}
|
|
|
|
abstract class Component extends Widget {
|
|
|
|
Component({ Key key })
|
|
: _order = _currentOrder + 1,
|
|
super._withKey(key);
|
|
|
|
bool _debugIsBuilding = false;
|
|
static Queue<Component> _debugComponentBuildTree = new Queue<Component>();
|
|
|
|
bool _dirty = true;
|
|
Widget _child;
|
|
|
|
void walkChildren(WidgetTreeWalker walker) {
|
|
if (_child != null)
|
|
walker(_child);
|
|
}
|
|
|
|
Widget get singleChild => _child;
|
|
|
|
bool _debugChildTaken = false;
|
|
|
|
void takeChild() {
|
|
assert(!_debugChildTaken);
|
|
assert(singleChild == _child);
|
|
assert(_child != null);
|
|
_child = null;
|
|
_renderObject = null;
|
|
assert(() { _debugChildTaken = true; return true; });
|
|
}
|
|
|
|
void remove() {
|
|
assert(_debugChildTaken || (_child != null && _renderObject != null));
|
|
super.remove();
|
|
_child = null;
|
|
_renderObject = null;
|
|
}
|
|
|
|
void detachRenderObject() {
|
|
assert(!_debugChildTaken);
|
|
if (_child != null)
|
|
_child.detachRenderObject();
|
|
}
|
|
|
|
void dependenciesChanged() {
|
|
// called by Inherited.sync()
|
|
_scheduleBuild();
|
|
}
|
|
|
|
dynamic _slot; // cached slot from the last time we were synced
|
|
|
|
void updateSlot(dynamic newSlot) {
|
|
_slot = newSlot;
|
|
if (_child != null)
|
|
_child.updateSlot(newSlot);
|
|
}
|
|
|
|
// order corresponds to _build_ order, not depth in the tree.
|
|
// All the Components built by a particular other Component will have the
|
|
// same order, regardless of whether one is subsequently inserted
|
|
// into another. The order is used to not tell a Component to
|
|
// rebuild if the Component that it built has itself been rebuilt.
|
|
final int _order;
|
|
static int _currentOrder = 0;
|
|
|
|
// There are three cases here:
|
|
// 1) Building for the first time:
|
|
// assert(_child == null && old == null)
|
|
// 2) Re-building (because a dirty flag got set):
|
|
// assert(_child != null && old == null)
|
|
// 3) Syncing against an old version (we are either new, or Stateful and pretending to be new)
|
|
// assert(_child == null && old != null)
|
|
void _sync(Component old, dynamic slot) {
|
|
assert(!_debugChildTaken);
|
|
assert(_child == null || old == null);
|
|
assert(old == null || old.isFromOldGeneration);
|
|
|
|
updateSlot(slot);
|
|
|
|
Widget oldChild;
|
|
if (old == null) {
|
|
oldChild = _child;
|
|
_child = null;
|
|
} else {
|
|
oldChild = old._child;
|
|
old._child = null;
|
|
assert(_child == null);
|
|
}
|
|
|
|
assert(() {
|
|
_debugIsBuilding = true;
|
|
_debugComponentBuildTree.add(this);
|
|
return true;
|
|
});
|
|
|
|
int lastOrder = _currentOrder;
|
|
_currentOrder = _order;
|
|
try {
|
|
_child = build();
|
|
assert(_child != null);
|
|
} catch (e, stack) {
|
|
_debugReportException('building $this', e, stack);
|
|
}
|
|
_currentOrder = lastOrder;
|
|
assert(() { _debugChildTaken = false; return true; });
|
|
try {
|
|
// even if build() failed (i.e. _child == null), we still call syncChild(), to remove the oldChild
|
|
_child = syncChild(_child, oldChild, slot);
|
|
assert(!_debugChildTaken); // we shouldn't be able to lose our child when we're syncing it!
|
|
assert(_child == null || _child.parent == this);
|
|
assert(_child == null || _child.renderObject != null);
|
|
} catch (e, stack) {
|
|
_debugReportException('syncing build output of $this\n old child: $oldChild\n new child: $_child', e, stack);
|
|
_child = null;
|
|
}
|
|
assert(() {
|
|
if (_child == null) {
|
|
try {
|
|
_child = new ErrorWidget()..setParent(this).._sync(null, slot);
|
|
} catch (e) {
|
|
print('(application is now in an unstable state - ignore any subsequent exceptions)');
|
|
}
|
|
}
|
|
_debugIsBuilding = false;
|
|
return identical(_debugComponentBuildTree.removeLast(), this);
|
|
});
|
|
|
|
_dirty = false;
|
|
_renderObject = _child.renderObject;
|
|
assert(_renderObject == renderObject); // in case a subclass reintroduces it
|
|
super._sync(old, slot);
|
|
}
|
|
|
|
void _markAsFromCurrentGeneration() {
|
|
if (_dirty)
|
|
return;
|
|
super._markAsFromCurrentGeneration();
|
|
}
|
|
|
|
void _buildIfDirty() {
|
|
if (!_dirty || !_mounted)
|
|
return;
|
|
assert(isFromOldGeneration);
|
|
assert(renderObject != null);
|
|
_sync(null, _slot);
|
|
}
|
|
|
|
void _scheduleBuild() {
|
|
assert(!_debugIsBuilding);
|
|
if (_dirty || !_mounted)
|
|
return;
|
|
_dirty = true;
|
|
_scheduleComponentForRender(this);
|
|
}
|
|
|
|
static void flushBuild() {
|
|
if (!_dirtyComponents.isEmpty)
|
|
_buildDirtyComponents();
|
|
}
|
|
|
|
Widget build();
|
|
|
|
void debugAddDetails(List<String> details) {
|
|
super.debugAddDetails(details);
|
|
if (_dirty)
|
|
details.add('dirty');
|
|
}
|
|
}
|
|
|
|
abstract class StatefulComponent extends Component {
|
|
|
|
StatefulComponent({ Key key }) : super(key: key);
|
|
|
|
bool _isStateInitialized = false;
|
|
|
|
bool get _hasState => _isStateInitialized;
|
|
|
|
bool retainStatefulNodeIfPossible(StatefulComponent newNode) {
|
|
assert(newNode != null);
|
|
assert(!newNode._isStateInitialized);
|
|
assert(this != newNode);
|
|
assert(Widget._canSync(this, newNode));
|
|
assert(_child != null);
|
|
|
|
newNode._child = _child;
|
|
_child = null;
|
|
_dirty = true;
|
|
|
|
return true;
|
|
}
|
|
|
|
// because our retainStatefulNodeIfPossible() method returns true,
|
|
// when _sync is called, our 'old' is actually the new instance that
|
|
// we are to copy state from.
|
|
void _sync(StatefulComponent old, dynamic slot) {
|
|
if (old == null) {
|
|
if (!_isStateInitialized) {
|
|
assert(mounted);
|
|
assert(!_wasMounted);
|
|
initState();
|
|
_isStateInitialized = true;
|
|
}
|
|
} else {
|
|
assert(_isStateInitialized);
|
|
assert(!old._isStateInitialized);
|
|
assert(old.isFromOldGeneration);
|
|
syncConstructorArguments(old);
|
|
}
|
|
super._sync(old, slot);
|
|
assert(_child != null);
|
|
}
|
|
|
|
// Stateful components can override initState if they want
|
|
// to do non-trivial work to initialize state. This is
|
|
// always called before build().
|
|
void initState() { }
|
|
|
|
// This is called by _sync(). Derived classes should override this
|
|
// method to update `this` to account for the new values the parent
|
|
// passed to `source`. Make sure to call super.syncConstructorArguments(source)
|
|
// unless you are extending StatefulComponent directly.
|
|
// A given source can be used multiple times as a source.
|
|
// The source must not be mutated.
|
|
void syncConstructorArguments(Component source);
|
|
|
|
// Calls function fn immediately and then schedules another build
|
|
// for this Component.
|
|
void setState(void fn()) {
|
|
assert(!_debugIsBuilding);
|
|
assert(_isStateInitialized);
|
|
fn();
|
|
_scheduleBuild();
|
|
}
|
|
|
|
void debugAddDetails(List<String> details) {
|
|
super.debugAddDetails(details);
|
|
details.add(_isStateInitialized ? 'stateful' : 'stateless');
|
|
}
|
|
}
|
|
|
|
Set<Component> _dirtyComponents = new Set<Component>();
|
|
bool _buildScheduled = false;
|
|
bool _inBuildDirtyComponents = false;
|
|
int _inLayoutCallbackBuilder = 0;
|
|
|
|
class LayoutCallbackBuilderHandle { bool _active = true; }
|
|
LayoutCallbackBuilderHandle enterLayoutCallbackBuilder() {
|
|
LayoutCallbackBuilderHandle result;
|
|
assert(() {
|
|
_inLayoutCallbackBuilder += 1;
|
|
result = new LayoutCallbackBuilderHandle();
|
|
return true;
|
|
});
|
|
return result;
|
|
}
|
|
void exitLayoutCallbackBuilder(LayoutCallbackBuilderHandle handle) {
|
|
assert(() {
|
|
assert(handle._active);
|
|
handle._active = false;
|
|
_inLayoutCallbackBuilder -= 1;
|
|
return true;
|
|
});
|
|
_endSyncPhase();
|
|
}
|
|
|
|
List<int> _debugFrameTimes = <int>[];
|
|
|
|
// TODO(ianh): Move this to Component
|
|
void _absorbDirtyComponents(List<Component> list) {
|
|
list.addAll(_dirtyComponents);
|
|
_dirtyComponents.clear();
|
|
list.sort((Component a, Component b) => a._order - b._order);
|
|
}
|
|
|
|
// TODO(ianh): Move this to Component
|
|
void _buildDirtyComponents() {
|
|
assert(!_dirtyComponents.isEmpty);
|
|
|
|
Stopwatch sw;
|
|
if (_shouldLogRenderDuration)
|
|
sw = new Stopwatch()..start();
|
|
|
|
while (!_dirtyComponents.isEmpty) {
|
|
_inBuildDirtyComponents = true;
|
|
try {
|
|
sky.tracing.begin('Component.flushBuild');
|
|
List<Component> sortedDirtyComponents = new List<Component>();
|
|
_absorbDirtyComponents(sortedDirtyComponents);
|
|
int index = 0;
|
|
while (index < sortedDirtyComponents.length) {
|
|
Component component = sortedDirtyComponents[index];
|
|
component._buildIfDirty();
|
|
if (_dirtyComponents.length > 0) {
|
|
// the following assert verifies that we're not rebuilding anyone twice in one frame
|
|
assert(_dirtyComponents.every((Component component) => !sortedDirtyComponents.contains(component)));
|
|
_absorbDirtyComponents(sortedDirtyComponents);
|
|
index = 0;
|
|
} else {
|
|
index += 1;
|
|
}
|
|
}
|
|
} finally {
|
|
_buildScheduled = false;
|
|
_inBuildDirtyComponents = false;
|
|
sky.tracing.end('Component.flushBuild');
|
|
}
|
|
_endSyncPhase();
|
|
}
|
|
|
|
if (_shouldLogRenderDuration) {
|
|
sw.stop();
|
|
_debugFrameTimes.add(sw.elapsedMicroseconds);
|
|
if (_debugFrameTimes.length >= 1000) {
|
|
_debugFrameTimes.sort();
|
|
const int i = 99;
|
|
print('Component.flushBuild: ${i+1}th fastest frame out of the last ${_debugFrameTimes.length}: ${_debugFrameTimes[i]} microseconds');
|
|
_debugFrameTimes.clear();
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
// TODO(ianh): Move this to Widget
|
|
void _endSyncPhase() {
|
|
try {
|
|
Widget._currentGeneration += 1;
|
|
Widget._notifyMountStatusChanged();
|
|
} catch (e, stack) {
|
|
_debugReportException('sending post-sync notifications', e, stack);
|
|
return null;
|
|
}
|
|
}
|
|
|
|
// TODO(ianh): Move this to Component
|
|
void _scheduleComponentForRender(Component component) {
|
|
_dirtyComponents.add(component);
|
|
if (!_buildScheduled) {
|
|
_buildScheduled = true;
|
|
scheduler.ensureVisualUpdate();
|
|
}
|
|
}
|
|
|
|
// RenderObjectWrappers correspond to a desired state of a
|
|
// RenderObject. They are fully immutable, except that a Widget which
|
|
// is a Component which lives within a RenderObjectWrapper's children
|
|
// list may be in-place replaced with the "old" instance if it has
|
|
// become stateful.
|
|
abstract class RenderObjectWrapper extends Widget {
|
|
|
|
RenderObjectWrapper({ Key key }) : super(key: key);
|
|
|
|
RenderObject createNode();
|
|
|
|
static final Map<RenderObject, RenderObjectWrapper> _nodeMap =
|
|
new HashMap<RenderObject, RenderObjectWrapper>();
|
|
static RenderObjectWrapper _getMounted(RenderObject node) => _nodeMap[node];
|
|
|
|
static Iterable<Widget> getWidgetsForRenderObject(RenderObject renderObject) sync* {
|
|
Widget target = RenderObjectWrapper._getMounted(renderObject);
|
|
if (target == null)
|
|
return;
|
|
RenderObject targetRenderObject = target.renderObject;
|
|
while (target != null && target.renderObject == targetRenderObject) {
|
|
yield target;
|
|
target = target.parent;
|
|
}
|
|
}
|
|
|
|
RenderObjectWrapper _ancestor;
|
|
void insertChildRenderObject(RenderObjectWrapper child, dynamic slot);
|
|
void detachChildRenderObject(RenderObjectWrapper child);
|
|
|
|
bool get _hasState => _renderObject != null;
|
|
|
|
void retainStatefulRenderObjectWrapper(RenderObjectWrapper newNode) {
|
|
newNode._renderObject = _renderObject;
|
|
newNode._ancestor = _ancestor;
|
|
}
|
|
|
|
RenderObjectWrapper findAncestorRenderObjectWrapper() {
|
|
Widget ancestor = parent;
|
|
while (ancestor != null && ancestor is! RenderObjectWrapper)
|
|
ancestor = ancestor.parent;
|
|
return ancestor;
|
|
}
|
|
|
|
void _sync(RenderObjectWrapper old, dynamic slot) {
|
|
// TODO(abarth): We should split RenderObjectWrapper into two pieces so that
|
|
// RenderViewObject doesn't need to inherit all this code it
|
|
// doesn't need.
|
|
assert(parent != null || this is RenderViewWrapper);
|
|
assert(old == null || old.isFromOldGeneration);
|
|
if (old == null) {
|
|
_renderObject = createNode();
|
|
assert(_renderObject != null);
|
|
_ancestor = findAncestorRenderObjectWrapper();
|
|
if (_ancestor != null)
|
|
_ancestor.insertChildRenderObject(this, slot);
|
|
} else {
|
|
_renderObject = old.renderObject;
|
|
_ancestor = old._ancestor;
|
|
assert(_renderObject != null);
|
|
}
|
|
assert(() {
|
|
_renderObject.debugExceptionContext = Component._debugComponentBuildTree.fold(' Widget build stack:', (String result, Component component) => result + '\n $component');
|
|
return true;
|
|
});
|
|
assert(_renderObject == renderObject); // in case a subclass reintroduces it
|
|
assert(renderObject != null);
|
|
assert(mounted);
|
|
_nodeMap[renderObject] = this;
|
|
syncRenderObject(old);
|
|
super._sync(old, slot);
|
|
}
|
|
|
|
void updateSlot(dynamic newSlot) {
|
|
// We never use the slot except during sync(), in which
|
|
// case our parent is handing it to us anyway.
|
|
// We don't need to propagate this to our children, since
|
|
// we give them their own slots for them to fit into us.
|
|
}
|
|
|
|
/// Override this function if your RenderObjectWrapper uses a [ParentDataNode]
|
|
/// to program parent data into children.
|
|
void updateParentData(RenderObject child, ParentDataNode node) { }
|
|
|
|
void syncRenderObject(RenderObjectWrapper old) {
|
|
assert(old == null || old.renderObject == renderObject);
|
|
ParentDataNode parentDataNode = null;
|
|
for (Widget current = parent; current != null; current = current.parent) {
|
|
assert(() {
|
|
if (current is ParentDataNode) {
|
|
Widget ancestor = current.parent;
|
|
while (ancestor is Component)
|
|
ancestor = ancestor.parent;
|
|
// ancestor might be null in two cases:
|
|
// - asking for the ancestor of a Widget that has no non-Component
|
|
// ancestors between itself and its AbstractWidgetRoot ancestor
|
|
// - if the node is just being synced to get its intrinsic
|
|
// dimensions, as e.g. MixedViewport does.
|
|
if (ancestor != null)
|
|
current.debugValidateAncestor(ancestor);
|
|
}
|
|
return true;
|
|
});
|
|
if (current is ParentDataNode) {
|
|
assert(parentDataNode == null);
|
|
parentDataNode = current;
|
|
} else if (current is RenderObjectWrapper) {
|
|
current.updateParentData(renderObject, parentDataNode);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// for use by subclasses that manage their children using lists
|
|
void syncChildren(List<Widget> newChildren, List<Widget> oldChildren) {
|
|
assert(newChildren != null);
|
|
assert(oldChildren != null);
|
|
assert(!identical(newChildren, oldChildren));
|
|
|
|
// This attempts to diff the new child list (this.children) with
|
|
// the old child list (old.children), and update our renderObject
|
|
// accordingly.
|
|
|
|
// The cases it tries to optimise for are:
|
|
// - the old list is empty
|
|
// - the lists are identical
|
|
// - there is an insertion or removal of one or more widgets in
|
|
// only one place in the list
|
|
// If a widget with a key is in both lists, it will be synced.
|
|
// Widgets without keys might be synced but there is no guarantee.
|
|
|
|
// The general approach is to sync the entire new list backwards, as follows:
|
|
// 1. Walk the lists from the top until you no longer have
|
|
// matching nodes. We don't sync these yet, but we now know to
|
|
// skip them below. We do this because at each sync we need to
|
|
// pass the pointer to the new next widget as the slot, which
|
|
// we can't do until we've synced the next child.
|
|
// 2. Walk the lists from the bottom, syncing nodes, until you no
|
|
// longer have matching nodes.
|
|
// At this point we narrowed the old and new lists to the point
|
|
// where the nodes no longer match.
|
|
// 3. Walk the narrowed part of the old list to get the list of
|
|
// keys and sync null with non-keyed items.
|
|
// 4. Walk the narrowed part of the new list backwards:
|
|
// * Sync unkeyed items with null
|
|
// * Sync keyed items with the source if it exists, else with null.
|
|
// 5. Walk the top list again but backwards, syncing the nodes.
|
|
// 6. Sync null with any items in the list of keys that are still
|
|
// mounted.
|
|
|
|
final ContainerRenderObjectMixin renderObject = this.renderObject; // TODO(ianh): Remove this once the analyzer is cleverer
|
|
assert(renderObject is ContainerRenderObjectMixin);
|
|
|
|
int childrenTop = 0;
|
|
int newChildrenBottom = newChildren.length-1;
|
|
int oldChildrenBottom = oldChildren.length-1;
|
|
|
|
// top of the lists
|
|
while ((childrenTop <= oldChildrenBottom) && (childrenTop <= newChildrenBottom)) {
|
|
Widget oldChild = oldChildren[childrenTop];
|
|
Widget newChild = newChildren[childrenTop];
|
|
if (oldChild != newChild && !oldChild.isFromOldGeneration) {
|
|
// even if the two nodes could in theory be synced, they can't really because
|
|
// it would seem that the old node has already been synced elsewhere in the tree.
|
|
break;
|
|
}
|
|
assert(oldChild.mounted);
|
|
if (!Widget._canSync(oldChild, newChild))
|
|
break;
|
|
childrenTop += 1;
|
|
}
|
|
|
|
Widget nextSibling;
|
|
|
|
// bottom of the lists
|
|
while ((childrenTop <= oldChildrenBottom) && (childrenTop <= newChildrenBottom)) {
|
|
Widget oldChild = oldChildren[oldChildrenBottom];
|
|
Widget newChild = newChildren[newChildrenBottom];
|
|
if (oldChild != newChild && !oldChild.isFromOldGeneration) {
|
|
// even if the two nodes could in theory be synced, they can't really because
|
|
// it would seem that the old node has already been synced elsewhere in the tree.
|
|
break;
|
|
}
|
|
assert(oldChild.mounted);
|
|
if (!Widget._canSync(oldChild, newChild))
|
|
break;
|
|
assert(oldChild == newChild || !newChild.mounted);
|
|
newChild = syncChild(newChild, oldChild, nextSibling);
|
|
assert(newChild.mounted);
|
|
newChildren[newChildrenBottom] = newChild;
|
|
nextSibling = newChild;
|
|
oldChildrenBottom -= 1;
|
|
newChildrenBottom -= 1;
|
|
}
|
|
|
|
// middle of the lists - old list
|
|
bool haveOldNodes = childrenTop <= oldChildrenBottom;
|
|
Map<Key, Widget> oldKeyedChildren;
|
|
if (haveOldNodes) {
|
|
oldKeyedChildren = new Map<Key, Widget>();
|
|
while (childrenTop <= oldChildrenBottom) {
|
|
Widget oldChild = oldChildren[oldChildrenBottom];
|
|
assert(oldChild.mounted);
|
|
if (oldChild.key != null) {
|
|
oldKeyedChildren[oldChild.key] = oldChild;
|
|
} else {
|
|
// Let's give up trying to sync this node with a new node. If this
|
|
// child is from the old generation, then we'll remove it from our
|
|
// child list. It it's not, then that means it's already been synced
|
|
// elsewhere and we should leave it alone.
|
|
if (oldChild.isFromOldGeneration)
|
|
syncChild(null, oldChild, null);
|
|
}
|
|
oldChildrenBottom -= 1;
|
|
}
|
|
}
|
|
|
|
// middle of the lists - new list
|
|
while (childrenTop <= newChildrenBottom) {
|
|
Widget oldChild;
|
|
Widget newChild = newChildren[newChildrenBottom];
|
|
if (haveOldNodes) {
|
|
Key key = newChild.key;
|
|
if (key != null) {
|
|
oldChild = oldKeyedChildren[newChild.key];
|
|
if (oldChild != null) {
|
|
if ((Widget._canSync(oldChild, newChild)) &&
|
|
(oldChild == newChild || oldChild.isFromOldGeneration)) {
|
|
// we found a match!
|
|
// remove it from oldKeyedChildren so we don't unsync it later
|
|
oldKeyedChildren.remove(key);
|
|
} else {
|
|
// Either it wasn't a match, or it's already been synced elsewhere in the tree.
|
|
// In either case, let's pretend we didn't see it for now.
|
|
oldChild = null;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
assert(oldChild == null || Widget._canSync(oldChild, newChild));
|
|
assert(oldChild == newChild || !newChild.mounted);
|
|
newChild = syncChild(newChild, oldChild, nextSibling);
|
|
assert(newChild.mounted);
|
|
assert(oldChild == newChild || oldChild == null || !oldChild.mounted);
|
|
newChildren[newChildrenBottom] = newChild;
|
|
nextSibling = newChild;
|
|
newChildrenBottom -= 1;
|
|
}
|
|
assert(oldChildrenBottom == newChildrenBottom);
|
|
assert(childrenTop == newChildrenBottom+1);
|
|
|
|
// now sync the top of the list
|
|
while (childrenTop > 0) {
|
|
childrenTop -= 1;
|
|
Widget oldChild = oldChildren[childrenTop];
|
|
assert(oldChild.mounted);
|
|
Widget newChild = newChildren[childrenTop];
|
|
assert(Widget._canSync(oldChild, newChild));
|
|
newChild = syncChild(newChild, oldChild, nextSibling);
|
|
assert(newChild.mounted);
|
|
assert(oldChild == newChild || oldChild == null || !oldChild.mounted);
|
|
newChildren[childrenTop] = newChild;
|
|
nextSibling = newChild;
|
|
}
|
|
|
|
// clean up any of the remaining middle nodes from the old list
|
|
if (haveOldNodes && !oldKeyedChildren.isEmpty) {
|
|
for (Widget oldChild in oldKeyedChildren.values)
|
|
if (oldChild.isFromOldGeneration)
|
|
syncChild(null, oldChild, null);
|
|
}
|
|
|
|
assert(renderObject == this.renderObject); // TODO(ianh): Remove this once the analyzer is cleverer
|
|
}
|
|
|
|
void dependenciesChanged() {
|
|
// called by Inherited.sync()
|
|
syncRenderObject(this);
|
|
}
|
|
|
|
void remove() {
|
|
assert(renderObject != null);
|
|
_nodeMap.remove(renderObject);
|
|
super.remove();
|
|
}
|
|
|
|
void detachRenderObject() {
|
|
assert(renderObject != null);
|
|
assert(_ancestor != null);
|
|
assert(_ancestor.renderObject != null);
|
|
_ancestor.detachChildRenderObject(this);
|
|
}
|
|
|
|
}
|
|
|
|
abstract class LeafRenderObjectWrapper extends RenderObjectWrapper {
|
|
|
|
LeafRenderObjectWrapper({ Key key }) : super(key: key);
|
|
|
|
void insertChildRenderObject(RenderObjectWrapper child, dynamic slot) {
|
|
assert(false);
|
|
}
|
|
|
|
void detachChildRenderObject(RenderObjectWrapper child) {
|
|
assert(false);
|
|
}
|
|
|
|
}
|
|
|
|
abstract class OneChildRenderObjectWrapper extends RenderObjectWrapper {
|
|
|
|
OneChildRenderObjectWrapper({ Key key, Widget child })
|
|
: _child = child, super(key: key);
|
|
|
|
Widget _child;
|
|
Widget get child => _child;
|
|
|
|
void walkChildren(WidgetTreeWalker walker) {
|
|
if (child != null)
|
|
walker(child);
|
|
}
|
|
|
|
Widget get singleChild => _child;
|
|
|
|
bool _debugChildTaken = false;
|
|
|
|
void takeChild() {
|
|
assert(!_debugChildTaken);
|
|
assert(singleChild == child);
|
|
assert(child != null);
|
|
_child = null;
|
|
assert(() { _debugChildTaken = true; return true; });
|
|
}
|
|
|
|
void syncRenderObject(RenderObjectWrapper old) {
|
|
assert(!_debugChildTaken);
|
|
super.syncRenderObject(old);
|
|
Widget oldChild = (old as OneChildRenderObjectWrapper)?.child;
|
|
Widget newChild = child;
|
|
_child = syncChild(newChild, oldChild, null);
|
|
assert((newChild == null && child == null) || (newChild != null && child.parent == this));
|
|
assert(oldChild == null || child == oldChild || oldChild.parent == null);
|
|
}
|
|
|
|
void insertChildRenderObject(RenderObjectWrapper child, dynamic slot) {
|
|
final renderObject = this.renderObject; // TODO(ianh): Remove this once the analyzer is cleverer
|
|
assert(renderObject is RenderObjectWithChildMixin);
|
|
assert(slot == null);
|
|
renderObject.child = child.renderObject;
|
|
assert(renderObject == this.renderObject); // TODO(ianh): Remove this once the analyzer is cleverer
|
|
}
|
|
|
|
void detachChildRenderObject(RenderObjectWrapper child) {
|
|
final renderObject = this.renderObject; // TODO(ianh): Remove this once the analyzer is cleverer
|
|
assert(renderObject is RenderObjectWithChildMixin);
|
|
assert(renderObject.child == child.renderObject);
|
|
renderObject.child = null;
|
|
assert(renderObject == this.renderObject); // TODO(ianh): Remove this once the analyzer is cleverer
|
|
}
|
|
}
|
|
|
|
abstract class MultiChildRenderObjectWrapper extends RenderObjectWrapper {
|
|
|
|
// In MultiChildRenderObjectWrapper subclasses, slots are the Widget
|
|
// nodes whose RenderObjects are to be used as the "insert before"
|
|
// sibling in ContainerRenderObjectMixin.add() calls
|
|
|
|
MultiChildRenderObjectWrapper({ Key key, List<Widget> children })
|
|
: this.children = children == null ? const [] : children,
|
|
super(key: key) {
|
|
assert(!_debugHasDuplicateIds());
|
|
}
|
|
|
|
final List<Widget> children;
|
|
|
|
void walkChildren(WidgetTreeWalker walker) {
|
|
for (Widget child in children)
|
|
walker(child);
|
|
}
|
|
|
|
void insertChildRenderObject(RenderObjectWrapper child, Widget slot) {
|
|
final renderObject = this.renderObject; // TODO(ianh): Remove this once the analyzer is cleverer
|
|
RenderObject nextSibling = slot?.renderObject;
|
|
assert(nextSibling == null || nextSibling is RenderObject);
|
|
assert(renderObject is ContainerRenderObjectMixin);
|
|
renderObject.add(child.renderObject, before: nextSibling);
|
|
assert(renderObject == this.renderObject); // TODO(ianh): Remove this once the analyzer is cleverer
|
|
}
|
|
|
|
void detachChildRenderObject(RenderObjectWrapper child) {
|
|
final renderObject = this.renderObject; // TODO(ianh): Remove this once the analyzer is cleverer
|
|
assert(renderObject is ContainerRenderObjectMixin);
|
|
assert(child.renderObject.parent == renderObject);
|
|
renderObject.remove(child.renderObject);
|
|
assert(renderObject == this.renderObject); // TODO(ianh): Remove this once the analyzer is cleverer
|
|
}
|
|
|
|
bool _debugHasDuplicateIds() {
|
|
var idSet = new HashSet<Key>();
|
|
for (var child in children) {
|
|
assert(child != null);
|
|
if (child.key == null)
|
|
continue; // when these nodes are reordered, we just reassign the data
|
|
|
|
if (!idSet.add(child.key)) {
|
|
throw 'If multiple keyed nodes exist as children of another node, they must have unique keys. $this has multiple children with key "${child.key}".';
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void syncRenderObject(MultiChildRenderObjectWrapper old) {
|
|
super.syncRenderObject(old);
|
|
List<Widget> oldChildren = old == null ? const <Widget>[] : old.children;
|
|
if (oldChildren == children) {
|
|
int index = children.length;
|
|
Widget nextSibling = null;
|
|
while (index > 0) {
|
|
index -= 1;
|
|
Widget child = children[index];
|
|
nextSibling = syncChild(child, child, nextSibling);
|
|
children[index] = nextSibling;
|
|
}
|
|
} else {
|
|
syncChildren(children, oldChildren);
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
class WidgetSkyBinding extends SkyBinding {
|
|
|
|
WidgetSkyBinding({ RenderView renderViewOverride: null })
|
|
: super(renderViewOverride: renderViewOverride);
|
|
|
|
static void initWidgetSkyBinding({ RenderView renderViewOverride: null }) {
|
|
if (SkyBinding.instance == null)
|
|
new WidgetSkyBinding(renderViewOverride: renderViewOverride);
|
|
assert(SkyBinding.instance is WidgetSkyBinding);
|
|
}
|
|
|
|
EventDisposition handleEvent(sky.Event event, BindingHitTestEntry entry) {
|
|
EventDisposition disposition = EventDisposition.ignored;
|
|
for (HitTestEntry entry in entry.result.path) {
|
|
if (entry.target is! RenderObject)
|
|
continue;
|
|
for (Widget target in RenderObjectWrapper.getWidgetsForRenderObject(entry.target)) {
|
|
if (target is Listener) {
|
|
EventDisposition targetDisposition = target._handleEvent(event);
|
|
if (targetDisposition == EventDisposition.consumed) {
|
|
return targetDisposition;
|
|
} else if (targetDisposition == EventDisposition.processed) {
|
|
disposition = EventDisposition.processed;
|
|
}
|
|
}
|
|
target = target._parent;
|
|
}
|
|
}
|
|
return combineEventDispositions(disposition, super.handleEvent(event, entry));
|
|
}
|
|
|
|
void beginFrame(double timeStamp) {
|
|
Component.flushBuild();
|
|
super.beginFrame(timeStamp);
|
|
}
|
|
|
|
}
|
|
|
|
abstract class App extends StatefulComponent {
|
|
|
|
App({ Key key }) : super(key: key);
|
|
|
|
void _handleEvent(sky.Event event) {
|
|
if (event.type == 'back')
|
|
onBack();
|
|
}
|
|
|
|
void didMount() {
|
|
super.didMount();
|
|
SkyBinding.instance.addEventListener(_handleEvent);
|
|
}
|
|
|
|
void didUnmount() {
|
|
super.didUnmount();
|
|
SkyBinding.instance.removeEventListener(_handleEvent);
|
|
}
|
|
|
|
void syncConstructorArguments(Component source) { }
|
|
|
|
// Override this to handle back button behavior in your app
|
|
// Call super.onBack() to finish the activity
|
|
void onBack() {
|
|
activity.finishCurrentActivity();
|
|
}
|
|
}
|
|
|
|
abstract class AbstractWidgetRoot extends StatefulComponent {
|
|
|
|
AbstractWidgetRoot() {
|
|
_mounted = true;
|
|
_scheduleComponentForRender(this);
|
|
}
|
|
|
|
void syncConstructorArguments(AbstractWidgetRoot source) {
|
|
assert(false);
|
|
// if we get here, it implies that we have a parent
|
|
}
|
|
|
|
void _buildIfDirty() {
|
|
assert(_dirty);
|
|
assert(_mounted);
|
|
assert(parent == null);
|
|
_sync(null, null);
|
|
}
|
|
|
|
}
|
|
|
|
class RenderViewWrapper extends OneChildRenderObjectWrapper {
|
|
RenderViewWrapper({ Key key, Widget child }) : super(key: key, child: child);
|
|
RenderView get renderObject => super.renderObject;
|
|
RenderView createNode() => SkyBinding.instance.renderView;
|
|
}
|
|
|
|
class AppContainer extends AbstractWidgetRoot {
|
|
AppContainer(this.app) {
|
|
assert(SkyBinding.instance is WidgetSkyBinding);
|
|
}
|
|
final App app;
|
|
Widget build() => new RenderViewWrapper(child: app);
|
|
}
|
|
|
|
AppContainer _container;
|
|
void runApp(App app, { RenderView renderViewOverride, bool enableProfilingLoop: false }) {
|
|
WidgetSkyBinding.initWidgetSkyBinding(renderViewOverride: renderViewOverride);
|
|
_container = new AppContainer(app);
|
|
if (enableProfilingLoop) {
|
|
new Timer.periodic(const Duration(milliseconds: 20), (_) {
|
|
app._scheduleBuild();
|
|
});
|
|
}
|
|
}
|
|
|
|
/// Prints a textual representation of the entire widget tree
|
|
void debugDumpApp() {
|
|
if (_container != null)
|
|
_container.toStringDeep().split('\n').forEach(print);
|
|
else
|
|
print('runApp() not yet called');
|
|
}
|
|
|
|
|
|
class RenderBoxToWidgetAdapter extends AbstractWidgetRoot {
|
|
|
|
RenderBoxToWidgetAdapter(
|
|
RenderObjectWithChildMixin<RenderBox> container,
|
|
this.builder
|
|
) : _container = container, super() {
|
|
assert(builder != null);
|
|
}
|
|
|
|
RenderObjectWithChildMixin<RenderBox> _container;
|
|
RenderObjectWithChildMixin<RenderBox> get container => _container;
|
|
void set container(RenderObjectWithChildMixin<RenderBox> value) {
|
|
if (_container != value) {
|
|
assert(value.child == null);
|
|
if (renderObject != null) {
|
|
assert(_container.child == renderObject);
|
|
_container.child = null;
|
|
}
|
|
_container = value;
|
|
if (renderObject != null) {
|
|
_container.child = renderObject;
|
|
assert(_container.child == renderObject);
|
|
}
|
|
}
|
|
}
|
|
|
|
final Builder builder;
|
|
|
|
void _buildIfDirty() {
|
|
super._buildIfDirty();
|
|
if (renderObject.parent == null) {
|
|
// we haven't attached it yet
|
|
assert(_container.child == null);
|
|
_container.child = renderObject;
|
|
}
|
|
assert(renderObject.parent == _container);
|
|
}
|
|
|
|
Widget build() => builder();
|
|
}
|
|
|
|
class ErrorWidget extends LeafRenderObjectWrapper {
|
|
RenderBox createNode() => new RenderErrorBox();
|
|
}
|
|
|
|
typedef void WidgetsExceptionHandler(String context, dynamic exception, StackTrace stack);
|
|
/// This callback is invoked whenever an exception is caught by the widget
|
|
/// system. The 'context' argument is a description of what was happening when
|
|
/// the exception occurred, and may include additional details such as
|
|
/// descriptions of the objects involved. The 'exception' argument contains the
|
|
/// object that was thrown, and the 'stack' argument contains the stack trace.
|
|
/// The callback is invoked after the information is printed to the console, and
|
|
/// could be used to print additional information, such as from
|
|
/// [debugDumpApp()].
|
|
WidgetsExceptionHandler debugWidgetsExceptionHandler;
|
|
void _debugReportException(String context, dynamic exception, StackTrace stack) {
|
|
print('------------------------------------------------------------------------');
|
|
'Exception caught while $context'.split('\n').forEach(print);
|
|
print('$exception');
|
|
print('Stack trace:');
|
|
'$stack'.split('\n').forEach(print);
|
|
print('Build stack:');
|
|
Component._debugComponentBuildTree.forEach((Component component) { print(' $component'); });
|
|
if (debugWidgetsExceptionHandler != null)
|
|
debugWidgetsExceptionHandler(context, exception, stack);
|
|
print('------------------------------------------------------------------------');
|
|
}
|