class PaddingTestRoute extends StatelessWidget {

  @override

  Widget build(BuildContext context) {

    return Padding(

      //上下左右各添加16像素补白

      padding: EdgeInsets.all(16.0),

      child: Column(

        //显式指定对齐方式为左对齐，排除对齐干扰

        crossAxisAlignment: CrossAxisAlignment.start,

        children: <Widget>[

          Padding(

            //左边添加8像素补白

            padding: const EdgeInsets.only(left: 8.0),

            child: Text("Hello world"),

          ),

          Padding(

            //上下各添加8像素补白

            padding: const EdgeInsets.symmetric(vertical: 8.0),

            child: Text("I am Jack"),

          ),

          Padding(

            // 分别指定四个方向的补白

            padding: const EdgeInsets.fromLTRB(20.0,.0,20.0,20.0),

            child: Text("Your friend"),

          )

        ],

      ),

    );

  }

}