| // Copyright 2019 The Flutter 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 'dart:ui'; |
| |
| import 'package:flutter/foundation.dart'; |
| import 'package:flutter/rendering.dart'; |
| |
| import 'framework.dart'; |
| |
| /// Applies a [ColorFilter] to its child. |
| @immutable |
| class ColorFiltered extends SingleChildRenderObjectWidget { |
| /// Creates a widget that applies a [ColorFilter] to its child. |
| /// |
| /// The [colorFilter] must not be null. |
| const ColorFiltered({@required this.colorFilter, Widget child, Key key}) |
| : assert(colorFilter != null), |
| super(key: key, child: child); |
| |
| /// The color filter to apply to the child of this widvget. |
| final ColorFilter colorFilter; |
| |
| @override |
| RenderObject createRenderObject(BuildContext context) => _ColorFilterRenderObject(colorFilter); |
| |
| @override |
| void updateRenderObject(BuildContext context, _ColorFilterRenderObject renderObject) { |
| renderObject..colorFilter = colorFilter; |
| } |
| |
| @override |
| void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| super.debugFillProperties(properties); |
| properties.add(DiagnosticsProperty<ColorFilter>('colorFilter', colorFilter)); |
| } |
| } |
| |
| class _ColorFilterRenderObject extends RenderProxyBox { |
| _ColorFilterRenderObject(this._colorFilter); |
| |
| ColorFilter get colorFilter => _colorFilter; |
| ColorFilter _colorFilter; |
| set colorFilter(ColorFilter value) { |
| assert(value != null); |
| if (value != _colorFilter) { |
| _colorFilter = value; |
| markNeedsPaint(); |
| } |
| } |
| |
| @override |
| bool get alwaysNeedsCompositing => child != null; |
| |
| @override |
| void paint(PaintingContext context, Offset offset) { |
| layer = context.pushColorFilter(offset, colorFilter, super.paint, oldLayer: layer); |
| } |
| } |