Flutter_学习记录_AppBar中取消leading的占位展示

• 将leading设置为null
• 将automaticallyImplyLeading设置为false

看看automaticallyImplyLeading的说明：

Controls whether we should try to imply the leading widget if null.

If true and AppBar.leading is null, automatically try to deduce what the leading widget should be. If false and AppBar.leading is null, leading space is given to AppBar.title. If leading widget is not null, this parameter has no effect.

意思就是说：

• 如果leading为null 并且 automaticallyImplyLeading为true ， 那么会保留leading的占位位置；
• 如果如果leading为null 并且automaticallyImplyLeading为false ， 那么会将leading的位置让给title；
• 如果leading不为null ， automaticallyImplyLeading这个设置失效。

代码如下：

@override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
      	
        leading: null,
        automaticallyImplyLeading: false,
        title: Container(
            margin: EdgeInsets.fromLTRB(0, 0, 0, 0), 
            height: Screenadapter.height(100),
            width:  Screenadapter.width(880) ,
            decoration: BoxDecoration(
              borderRadius: BorderRadius.circular(20),
              color: Color.fromARGB(10, 0, 0, 0)
            ),
            child: Row(
              crossAxisAlignment: CrossAxisAlignment.center,
              children: [
                Padding(padding: EdgeInsets.fromLTRB(10, 0, 0, 0), child: Icon(Icons.search, color: Colors.black26)),
                Expanded(child: Text("耳机", style: TextStyle(color: Colors.black45, fontSize: Screenadapter.fontSize(36)))),
                Padding(padding: EdgeInsets.fromLTRB(0, 0, 10, 0), child: Icon(FangXMIcon.saomiao, color: Colors.black26)),
              ],
            ),
          ),
        centerTitle: true,
        actions: [
          Container(
            padding: EdgeInsets.fromLTRB(0, 0, 0, 0),
            width: Screenadapter.width(124),
            height: Screenadapter.height(100),
            child: InkWell(
              child: Icon(FangXMIcon.xiaoxi, color: Colors.black54 ),
            ),
          )
        ],
      ),
      body: const Center(
        child: Text(
          'GiveView is working',
          style: TextStyle(fontSize: 20),
        ),
      ),
    );
  }

效果如下：