flutter中关于Container配置alignment不显示子组件问题。

Question

比如我想把虚线显示在其父组件的底部

代码如下:

Widget MyWidgetsTest() {    
  
  //DashedLine(虚线)  
  LJDashedLine dashedLine = LJDashedLine(axis: Axis.horizontal);  
  Container dashedLineContainer = Container(  
  width: 200,  
    height: 100,  
    child: dashedLine,//虚线  
  color: Colors.yellow,  
//    alignment: Alignment.bottomLeft, //1.无效，不显示dashedLine 
//    padding: EdgeInsets.fromLTRB(0, 97, 0, 0),//2.这种倒是可以显示到底部
  );  
  
  return dashedLineContainer;  
}

class LJDashedLine extends StatelessWidget {
//...省略部分代码
@override  
  Widget build(BuildContext context) {  
  // TODO: implement build  
  return LayoutBuilder(  
  builder: (BuildContext context, BoxConstraints constraints) {  
  
  return Flex(  
  direction: this.axis,  
            mainAxisAlignment: MainAxisAlignment.spaceBetween,  
//          mainAxisSize: MainAxisSize.min,  
  children: List.generate(CalcDashedCountWithConstraints(constraints), (int index) {  
  return SizedBox(  
  width: dashedWidth,  
                height: dashedHeight,  
                child: DecoratedBox(  
  decoration: BoxDecoration(color: dashedColor),  
                ),  
              );  
            }),  
          );  
      },  
    );  
  }

}

如上，这样运行虚线默认是居中显示的，然后我想在dashedLine父组件Container中调整alignment: Alignment.bottomLeft让虚线显示在底部为啥虚线就直接不显示了呢....### 问题描述

Answer 1

没人吗，自己顶一下，虽然我知道有几种方法可以解决这个问题，但是我却不知道为啥Alignment.bottomLeft设置无效不说还把dashedLine给搞没了。。