Scaffold(
      appBar: AppBar(
        title: Text("GoodsInfo"),
      ),
      body: Center(
        child: RaisedButton(
          child: Text("下一步"),
          onPressed: (){
          	//替换当前Widget, /Search返回当前Widget的上一页, 而不是当前Widget.
            Navigator.pushReplacementNamed(context, "/Search", arguments:"Are you Search Page?");
          },
        ),
      ),
    );

Scaffold(
      //页面里定义一个浮动按钮
      floatingActionButton: FloatingActionButton(
        child: Text("返回"),
        onPressed: (){
          //当浮动按钮被点击时, 弹出当前页面, 返回上一页
          Navigator.of(context).pushAndRemoveUntil(
              MaterialPageRoute(
                  builder: (BuildContext context) => HomeContent()
              ),
              (route) => route == null
          );
        },
      ),
      appBar: AppBar(
        title: Text("I'm searching"),
      ),
      body: Center(
        child: Text(this.arguments.toString()),
      ),
    );