mirror of
https://github.com/flutter/flutter.git
synced 2026-02-20 02:29:02 +08:00
396a04df4a
- add a checkbox to the stock app, so that we're testing the checkbox widget (it's not currently wired up to anything, that can come later) - make InkSplash use FlexContainer so that we can use flex in the popup menu items - make effen's Text be more similar to Image and Container, so that it can be styled - make layout.dart's RenderCSSText correctly support being styled - also fixes a bug with the stock list where we were rendering one too few a row when scrolling - check in the code to dump the DOM so I don't have to keep remembering how to do this R=eseidel@chromium.org Review URL: https://codereview.chromium.org/1134163003
107 lines
2.9 KiB
Dart
107 lines
2.9 KiB
Dart
// Copyright 2015 The Chromium Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
import '../animation/scroll_behavior.dart';
|
|
import '../debug/tracing.dart';
|
|
import '../fn.dart';
|
|
import 'dart:math' as math;
|
|
import 'dart:async';
|
|
import 'scrollable.dart';
|
|
|
|
abstract class FixedHeightScrollable extends Scrollable {
|
|
static final Style _style = new Style('''
|
|
overflow: hidden;
|
|
position: relative;
|
|
will-change: transform;'''
|
|
);
|
|
|
|
static final Style _scrollAreaStyle = new Style('''
|
|
position:relative;
|
|
will-change: transform;'''
|
|
);
|
|
|
|
FixedHeightScrollable({
|
|
Object key
|
|
}) : super(key: key);
|
|
|
|
ScrollBehavior createScrollBehavior() => new OverscrollBehavior();
|
|
OverscrollBehavior get scrollBehavior => super.scrollBehavior as OverscrollBehavior;
|
|
|
|
double _height = 0.0;
|
|
double _itemHeight;
|
|
|
|
int _itemCount = 0;
|
|
int get itemCount => _itemCount;
|
|
void set itemCount (int value) {
|
|
if (_itemCount != value) {
|
|
_itemCount = value;
|
|
if (_itemHeight != null)
|
|
scrollBehavior.contentsHeight = _itemHeight * _itemCount;
|
|
}
|
|
}
|
|
|
|
void _measureHeights() {
|
|
trace('FixedHeightScrollable::_measureHeights', () {
|
|
if (_itemHeight != null)
|
|
return;
|
|
var root = getRoot();
|
|
if (root == null)
|
|
return;
|
|
var item = root.firstChild.firstChild;
|
|
if (item == null)
|
|
return;
|
|
setState(() {
|
|
_height = root.height;
|
|
assert(_height > 0);
|
|
_itemHeight = item.height;
|
|
assert(_itemHeight > 0);
|
|
scrollBehavior.containerHeight = _height;
|
|
scrollBehavior.contentsHeight = _itemHeight * _itemCount;
|
|
});
|
|
});
|
|
}
|
|
|
|
UINode buildContent() {
|
|
var itemNumber = 0;
|
|
var drawCount = 1;
|
|
var transformStyle = '';
|
|
|
|
if (_itemHeight == null)
|
|
new Future.microtask(_measureHeights);
|
|
|
|
if (_height > 0.0 && _itemHeight != null) {
|
|
if (scrollOffset < 0.0) {
|
|
double visibleHeight = _height + scrollOffset;
|
|
drawCount = (visibleHeight / _itemHeight).round() + 1;
|
|
transformStyle =
|
|
'transform: translateY(${(-scrollOffset).toStringAsFixed(2)}px)';
|
|
} else {
|
|
drawCount = (_height / _itemHeight).ceil() + 1;
|
|
double alignmentDelta = -scrollOffset % _itemHeight;
|
|
if (alignmentDelta != 0.0)
|
|
alignmentDelta -= _itemHeight;
|
|
|
|
double drawStart = scrollOffset + alignmentDelta;
|
|
itemNumber = math.max(0, (drawStart / _itemHeight).floor());
|
|
|
|
transformStyle =
|
|
'transform: translateY(${(alignmentDelta).toStringAsFixed(2)}px)';
|
|
}
|
|
}
|
|
|
|
return new Container(
|
|
style: _style,
|
|
children: [
|
|
new Container(
|
|
style: _scrollAreaStyle,
|
|
inlineStyle: transformStyle,
|
|
children: buildItems(itemNumber, drawCount)
|
|
)
|
|
]
|
|
);
|
|
}
|
|
|
|
List<UINode> buildItems(int start, int count);
|
|
}
|