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f183f6a173
This CL pulled an implementation of position: absolute in RenderStackContainer. R=eseidel@chromium.org, ianh@google.com Review URL: https://codereview.chromium.org/1166363002.
116 lines
3.8 KiB
Dart
116 lines
3.8 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 'box.dart';
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import 'object.dart';
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class StackParentData extends BoxParentData with ContainerParentDataMixin<RenderBox> {
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double top;
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double right;
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double bottom;
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double left;
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void merge(StackParentData other) {
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if (other.top != null)
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top = other.top;
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if (other.right != null)
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right = other.right;
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if (other.bottom != null)
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bottom = other.bottom;
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if (other.left != null)
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left = other.left;
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super.merge(other);
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}
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String toString() => '${super.toString()}; top=$top; right=$right; bottom=$bottom, left=$left';
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}
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class RenderStack extends RenderBox with ContainerRenderObjectMixin<RenderBox, StackParentData>,
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RenderBoxContainerDefaultsMixin<RenderBox, StackParentData> {
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RenderStack({
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List<RenderBox> children
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}) {
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if (children != null)
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children.forEach((child) { add(child); });
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}
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void setParentData(RenderBox child) {
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if (child.parentData is! StackParentData)
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child.parentData = new StackParentData();
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}
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double getMinIntrinsicWidth(BoxConstraints constraints) {
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return constraints.constrainWidth(double.INFINITY);
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}
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double getMaxIntrinsicWidth(BoxConstraints constraints) {
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return constraints.constrainWidth(double.INFINITY);
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}
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double getMinIntrinsicHeight(BoxConstraints constraints) {
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return constraints.constrainHeight(double.INFINITY);
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}
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double getMaxIntrinsicHeight(BoxConstraints constraints) {
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return constraints.constrainHeight(double.INFINITY);
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}
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void performLayout() {
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size = constraints.constrain(Size.infinite);
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assert(size.width < double.INFINITY);
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assert(size.height < double.INFINITY);
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BoxConstraints innerConstraints = new BoxConstraints.loose(size);
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RenderBox child = firstChild;
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while (child != null) {
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assert(child.parentData is StackParentData);
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StackParentData parentData = child.parentData;
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BoxConstraints childConstraints = innerConstraints;
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if (parentData.left != null && parentData.right != null)
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childConstraints = childConstraints.applyWidth(parentData.right - parentData.left);
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else if (parentData.left != null)
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childConstraints = childConstraints.applyMaxWidth(size.width - parentData.left);
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else if (parentData.right != null)
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childConstraints = childConstraints.applyMaxWidth(size.width - parentData.right);
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if (parentData.top != null && parentData.bottom != null)
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childConstraints = childConstraints.applyHeight(parentData.bottom - parentData.top);
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else if (parentData.top != null)
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childConstraints = childConstraints.applyMaxHeight(size.height - parentData.top);
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else if (parentData.bottom != null)
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childConstraints = childConstraints.applyMaxHeight(size.width - parentData.bottom);
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child.layout(childConstraints);
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double x = 0.0;
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if (parentData.left != null)
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x = parentData.left;
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else if (parentData.right != null)
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x = size.width - parentData.right - child.size.width;
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assert(x >= 0.0 && x + child.size.width <= size.width);
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double y = 0.0;
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if (parentData.top != null)
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y = parentData.top;
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else if (parentData.bottom != null)
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y = size.height - parentData.bottom - child.size.height;
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assert(y >= 0.0 && y + child.size.height <= size.height);
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parentData.position = new Point(x, y);
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child = child.parentData.nextSibling;
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}
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}
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void hitTestChildren(HitTestResult result, { Point position }) {
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defaultHitTestChildren(result, position: position);
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}
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void paint(RenderObjectDisplayList canvas) {
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defaultPaint(canvas);
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}
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}
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