如何在Flutter中的行小部件内的容器上添加边框？

Question

        Container(
    //            decoration: BoxDecoration(
    //              border: Border.all(color: Colors.black45),
    //              borderRadius: BorderRadius.circular(8.0),
    //            ),
                child: Row(
                  children: <Widget>[
                    Container(
                      child: Text("hi"),
                      margin : EdgeInsets.fromLTRB(20, 8, 8, 16),
                      width: MediaQuery.of(context).size.width *0.42,
                      height: 90,
                      color: Colors.black12,
                    ),

                    Container(
                      child: Text("Hi"),
                      margin: EdgeInsets.fromLTRB(16, 8, 8, 16),
                      width: MediaQuery.of(context).size.width * 0.42 ,
                      height: 90,
                      color: Colors.black12,
                    )
                  ],
                ),
              ),

我可以在外部容器上使用Box装饰添加边框，但是当我尝试在内部容器上执行相同操作时，这使我出错。问题出在哪里，如何解决？

Answer 1

这应该起作用：

Container(
  child: Row(
    children: <Widget>[
      Container(
        decoration: BoxDecoration(
          border: Border.all(color: Colors.black45),
          borderRadius: BorderRadius.circular(8.0),
          color: Colors.black12,  //add it here
        ),
        child: Text("hi"),
        margin : EdgeInsets.fromLTRB(20, 8, 8, 16),
        width: MediaQuery.of(context).size.width *0.42,
        height: 90,
        //color: Colors.black12,    //must be removed
      ),

      Container(
        decoration: BoxDecoration(
          border: Border.all(color: Colors.black45),
          borderRadius: BorderRadius.circular(8.0),
          color: Colors.black12,  //add it here
        ),
        child: Text("Hi"),
        margin: EdgeInsets.fromLTRB(16, 8, 8, 16),
        width: MediaQuery.of(context).size.width * 0.42 ,
        height: 90,
        //color: Colors.black12,      // must be removed
      )
    ],
  ),
),

Answer 2

     Container(
          child: Row(
            children: <Widget>[
              Container(
                child: Text("hi"),
                margin: EdgeInsets.fromLTRB(20, 8, 8, 16),
                width: MediaQuery.of(context).size.width * 0.42,
                height: 90,
                decoration: BoxDecoration(
                    borderRadius: BorderRadius.all(Radius.circular(4)),
                    shape: BoxShape.rectangle,
                    border: Border.all(
                      color: Colors.blue,
                      width: 4,
                    )),
              ),
              Container(
                child: Text("Hi"),
                margin: EdgeInsets.fromLTRB(16, 8, 8, 16),
                width: MediaQuery.of(context).size.width * 0.42,
                height: 90,
                decoration: BoxDecoration(
                    borderRadius: BorderRadius.all(Radius.circular(4)),
                    shape: BoxShape.rectangle,
                    border: Border.all(
                      color: Colors.blue,
                      width: 4,
                    )),
              )
            ],
          ),
        ),