// 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 'package:flutter_test/flutter_test.dart'; import 'package:flutter/rendering.dart'; import 'package:flutter/widgets.dart'; class TestSingleChildLayoutDelegate extends SingleChildLayoutDelegate { BoxConstraints constraintsFromGetSize; BoxConstraints constraintsFromGetConstraintsForChild; Size sizeFromGetPositionForChild; Size childSizeFromGetPositionForChild; @override Size getSize(BoxConstraints constraints) { if (!RenderObject.debugCheckingIntrinsics) constraintsFromGetSize = constraints; return new Size(200.0, 300.0); } @override BoxConstraints getConstraintsForChild(BoxConstraints constraints) { assert(!RenderObject.debugCheckingIntrinsics); constraintsFromGetConstraintsForChild = constraints; return new BoxConstraints( minWidth: 100.0, maxWidth: 150.0, minHeight: 200.0, maxHeight: 400.0 ); } @override Offset getPositionForChild(Size size, Size childSize) { assert(!RenderObject.debugCheckingIntrinsics); sizeFromGetPositionForChild = size; childSizeFromGetPositionForChild = childSize; return Offset.zero; } bool shouldRelayoutCalled = false; bool shouldRelayoutValue = false; @override bool shouldRelayout(_) { assert(!RenderObject.debugCheckingIntrinsics); shouldRelayoutCalled = true; return shouldRelayoutValue; } } Widget buildFrame(SingleChildLayoutDelegate delegate) { return new Center(child: new CustomSingleChildLayout(delegate: delegate, child: new Container())); } void main() { testWidgets('Control test for CustomSingleChildLayout', (WidgetTester tester) async { TestSingleChildLayoutDelegate delegate = new TestSingleChildLayoutDelegate(); await tester.pumpWidget(buildFrame(delegate)); expect(delegate.constraintsFromGetSize.minWidth, 0.0); expect(delegate.constraintsFromGetSize.maxWidth, 800.0); expect(delegate.constraintsFromGetSize.minHeight, 0.0); expect(delegate.constraintsFromGetSize.maxHeight, 600.0); expect(delegate.constraintsFromGetConstraintsForChild.minWidth, 0.0); expect(delegate.constraintsFromGetConstraintsForChild.maxWidth, 800.0); expect(delegate.constraintsFromGetConstraintsForChild.minHeight, 0.0); expect(delegate.constraintsFromGetConstraintsForChild.maxHeight, 600.0); expect(delegate.sizeFromGetPositionForChild.width, 200.0); expect(delegate.sizeFromGetPositionForChild.height, 300.0); expect(delegate.childSizeFromGetPositionForChild.width, 150.0); expect(delegate.childSizeFromGetPositionForChild.height, 400.0); }); testWidgets('Test SingleChildDelegate shouldRelayout method', (WidgetTester tester) async { TestSingleChildLayoutDelegate delegate = new TestSingleChildLayoutDelegate(); await tester.pumpWidget(buildFrame(delegate)); // Layout happened because the delegate was set. expect(delegate.constraintsFromGetConstraintsForChild, isNotNull); // i.e. layout happened expect(delegate.shouldRelayoutCalled, isFalse); // Layout did not happen because shouldRelayout() returned false. delegate = new TestSingleChildLayoutDelegate(); delegate.shouldRelayoutValue = false; await tester.pumpWidget(buildFrame(delegate)); expect(delegate.shouldRelayoutCalled, isTrue); expect(delegate.constraintsFromGetConstraintsForChild, isNull); // Layout happened because shouldRelayout() returned true. delegate = new TestSingleChildLayoutDelegate(); delegate.shouldRelayoutValue = true; await tester.pumpWidget(buildFrame(delegate)); expect(delegate.shouldRelayoutCalled, isTrue); expect(delegate.constraintsFromGetConstraintsForChild, isNotNull); }); }