Size _widgetSize = Size.zero; Widget build(BuildContext context){ Offset o = Offset(_widgetSize.size.width/2, _widgetSize.size.height/2); returnTransform.translate( offset: o, child: MeasurableWidget(child: ..., onSized: _handleWidgetSized); ); } void_handleWidgetSized(Size value) => ...
Size _widgetSize = Size.zero; Widget build(BuildContext context){ Offset o = Offset(_widgetSize.size.width/2, _widgetSize.size.height/2); return Transform.translate( offset: o, child: MeasurableWidget(child: ..., onSized: _handleWidgetSized); void _handleWidgetSized(Size value) => setS...
Inside the performLayout widget, you need to get the child's size and call the callback if the current size is different than the previous size. class WidgetSizeRenderObject extends RenderProxyBox { final OnWidgetSizeChange onSizeChange; Size? currentSize; WidgetSizeRenderObject(this.onSizeChange...
final topLeftPosition=box.localToGlobal(Offset.zero); returntopLeftPosition.dy; 2. 可以通过context.size获取当前控件的尺寸和位置offset信息 下面是示例,通过contex.size.height可以拿到child控件的高度 1 2 3 4 5 6 7 8 9 10 11 12 13 14 classHeightReporter extends StatelessWidget { final Widget child;...
}@overrideWidgetbuild(BuildContext context){returnScaffold(appBar:AppBar(),body:Container(color:Colors.green,child:Stack(children:!show?getCustomChildren():showChildren,),),);}} 这段代码的思路为: 1.建立一个GlobalKey数组对传递进来的Widget数组提前进行渲染知道并且都赋予GlobalKey保存到数组里。
child: buildChildWidget(), onChildSizeChanged: (size) => handleNewChildSize(size), ); 简单的理论 当编写一个包含子窗口的自定义窗口小部件时,我们需要知道一些重要的事情: 对于每个自定义小部件,我们需要编写它的 Element 和(有时) RenderObject 实现 ...
children: <Widget>[ new Container( key:_myKey, color:Colors.black12, child: new Column( mainAxisSize: MainAxisSize.min, children: <Widget>[ new Text("获取大小",style: new TextStyle(fontSize: 10.0),), new Text("获取大小",style: new TextStyle(fontSize: 12.0),), ...
我们平时在开发中的过程中通常都会获取屏幕或者 widget 的宽高用来做一些事情,在 Flutter 中,我们可以使用如下方法来获取屏幕或者 widget 的宽高。 MediaQuery 一般情况下,我们会使用如下方式去获取 widget 的宽高: finalsize =MediaQuery.of(context).size;finalwidth =size.width;finalheight =size.height; ...
title:Text(widget.title), ), body:Center( child:Container( width:400, height:400, color:Colors.black45.withAlpha(128), child:Flow( delegate:TestFlowFlowDelegate(), children:[Container(width:80.0, height:80.0, color:Colors.pink),Container(width:80.0, height:80.0, color:Colors.yellow),Containe...
您可以为包装child小部件的小部件设置GlobalKey，例如Container或IntrinsicHeight(将其高度设置为其子部件的...