点击容器触发onTap()处理程序,但不会显示任何墨水飞溅效果。

class _MyHomePageState extends State<MyHomePage> {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(
        title: new Text(widget.title),
      ),
      body: new Center(
        child: new InkWell(
          onTap: (){print("tapped");},
          child: new Container(
            width: 100.0,
            height: 100.0,
            color: Colors.orange,
          ),
        ),
      ),
    );
  }
}

我试着把InkWell放在容器里,但徒劳。


当前回答

InkWell小部件必须有一个材质小部件作为祖先,否则它不能显示效果。例如: 材料( 孩子:InkWell( 孩子:..... 你必须添加onTap方法来查看实际效果 按钮{RaisedButton,FlatButton等}。 例如->材料( 孩子:InkWell( onTap:(){} 孩子:.....

让我们来看看要点,看看下面的例子,试着理解 InkWell的实际概念。

In Below example Material is parent of InkWell with onTap but it still not working. Please try to understand the concept of it. You should provide some margin to container or other widget to show the effects. Actually below code working fine but we can't see because we did not provide any margin or align so it has no space to show the effects. Widget build(BuildContext context) { return Center( child: Material( child: new InkWell( onTap: () { print("tapped"); }, child: new Container( width: 100.0, height: 100.0, color: Colors.orange, ), ), ), ); } Below example show InkWell effects only to upwards because we provide space {margin}. Widget build(BuildContext context) { return Center( child: Material( child: new InkWell( onTap: () { print("tapped"); }, child: new Container( margin: EdgeInsets.only(top: 100.0), width: 100.0, height: 100.0, color: Colors.orange, ), ), ), ); } Below exp. show the effects in all the page because center create margin from all the side. Centre align it's child widget from top, left, right and bottom. Widget build(BuildContext context) { return Center( child: Material( child: new InkWell( onTap: () { print("tapped"); }, child: Center( child: new Container( width: 100.0, height: 100.0, color: Colors.orange, ), ), ), ), ); }

其他回答

为材质添加透明颜色在我的案例中起作用:

  child: new Material(
    color: Colors.transparent
    child: new InkWell(
      onTap: (){},
      child: new Container(
        width: 100.0,
        height: 100.0,
        color: Colors.amber,
      ),
    ),
  ),

添加onTap:(){}监听器后,涟漪效应应该工作良好。如果你在InkWell()小部件中使用BoxShadow(),它就不工作了。

更好的方法是使用Ink小部件而不是其他小部件。

而不是在容器内定义颜色,你可以在墨水小部件本身中定义它。

下面的代码将工作。

Ink(
  color: Colors.orange,
  child: InkWell(
    child: Container(
      width: 100,
      height: 100,
    ),
    onTap: () {},
  ),
)

不要忘记在InkWell中添加onTap:(){},否则它会 也没有显示出涟漪效应。

InkWell()将永远不会显示涟漪效应,直到您添加

onTap : () {} 

或任何回调,如onDoubleTap, onLongPress等。

当你指定这个参数时,InkWell才会开始监听你的点击。

我认为给容器添加颜色是在掩盖墨水的效果

https://api.flutter.dev/flutter/material/InkWell/InkWell.html

这段代码似乎可以工作

  body: new Center(
    child: new Container(
      child: new Material(
        child: new InkWell(
          onTap: (){print("tapped");},
          child: new Container(
            width: 100.0,
            height: 100.0,
          ),
        ),
        color: Colors.transparent,
      ),
      color: Colors.orange,
    ),
  ),

只要点击中间的方块。

编辑:我找到了错误报告。https://github.com/flutter/flutter/issues/3782

This is actually as expected, though we should update the docs to make it clearer. What's going on is that the Material spec says that the splashes are actually ink on the Material. So when we splash, what we do is we literally have the Material widget do the splash. If you have something on top of the Material, we splash under it, and you can't see it. I have wanted to add a "MaterialImage" widget that conceptually prints its image into the Material as well so that then the splashes would be over the image. We could have a MaterialDecoration which does something similar for a Decoration. Or we could have Material itself take a decoration. Right now it takes a color, but we could extend that to taking a whole decoration. It's not clear whether it's really material-spec-compatible to have a material with a gradient, though, so I'm not sure whether we should do that. In the short run, if you just need a workaround, you can put a Material on top of the container, with the material set to use the "transparency" type, and then put the ink well inside that.

--希克西

更新:Hixie去年合并了一个新的Ink解决方案。墨水提供了一种方便的方式溅在图像。

  testWidgets('Does the Ink widget render anything', (WidgetTester tester) async {
    await tester.pumpWidget(
      new Material(
        child: new Center(
          child: new Ink(
            color: Colors.blue,
            width: 200.0,
            height: 200.0,
            child: new InkWell(
              splashColor: Colors.green,
              onTap: () { },
            ),
          ),
        ),
      ),
    );


Material(
  color: Colors.grey[800],
  child: Center(
    child: Ink.image(
      image: AssetImage('cat.jpeg'),
      fit: BoxFit.cover,
      width: 300.0,
      height: 200.0,
      child: InkWell(
        onTap: () { /* ... */ },
        child: Align(
          alignment: Alignment.topLeft,
          child: Padding(
            padding: const EdgeInsets.all(10.0),
            child: Text('KITTEN', style: TextStyle(fontWeight: FontWeight.w900, color: Colors.white)),
          ),
        )
      ),
    ),
  ),
)

请注意:我没有测试新的墨水小部件。我从ink_paint_test中拷贝了代码。dart和Ink类文档

https://github.com/Hixie/flutter/blob/1f6531984984f52328e66c0cd500a8d517964564/packages/flutter/test/material/ink_paint_test.dart

https://github.com/flutter/flutter/pull/13900

https://api.flutter.dev/flutter/material/Ink-class.html