自定义AppBar Flutter

Question

我试图实现类似以下的东西,

我很吵,所以我无法弄明白.我需要一个带抽屉和动作的自定义AppBar,但是像图像一样排列.

我在标题小部件中尝试了StackView

appBar: AppBar(
    title: Stack(
      children: <Widget>[
        Container(
          width: double.infinity,
          color: CustomColors.accentColor,
        ),
        Text(
          'Title',
          style: TextStyle(fontSize: 22.0, color: CustomColors.primaryDark),
        ),
      ],
    ),
  ),

但我得到这样的东西

有人可以帮我吗？谢谢.

Answer 1

截屏：

代码：

• 使用 flexibleSpace

  Scaffold(
    appBar: AppBar(
      toolbarHeight: 120, // Set this height
      flexibleSpace: Container(
        color: Colors.orange,
        child: Column(
          children: [
            Text('One'),
            Text('Two'),
            Text('Three'),
            Text('Four'),
          ],
        ),
      ),
    ),
  )
  

• 使用 PreferredSize

  Scaffold(
    appBar: PreferredSize(
      preferredSize: Size.fromHeight(120), // Set this height
      child: Container(
        color: Colors.orange,
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text('One'),
            Text('Two'),
            Text('Three'),
            Text('Four'),
          ],
        ),
      ),
    ),
  )
  

Answer 2

只需将整个内容包装在Stack 中。然后 AppBar 定位为最后一个小部件，并在一些小部件（例如容器）之间，这样 AppBar 就可以漂浮在它们上面。

 Widget setPage() {
    Color red800 = Colors.red[800];

    return Stack(
      children: <Widget>[
        Container(     // Background
          child: Center(
             child: Text("Home", style: TextStyle(fontSize: 25.0,
              fontWeight: FontWeight.w600,
              color: Colors.white),),),
          color: red800,
          height: MediaQuery.of(context).size.height * 0.2,
          width: MediaQuery.of(context).size.width,
        ),

        Container(),   // Required some widget in between to float AppBar

        Positioned(    // To take AppBar Size only
          top: 100.0,
          left: 20.0,
          right: 20.0,
          child: AppBar(
            backgroundColor: Colors.white,
            leading: Icon(Icons.menu, color: red800,),
            primary: false,
            title: TextField(
                decoration: InputDecoration(
                    hintText: "Search",
                    border: InputBorder.none,
                    hintStyle: TextStyle(color: Colors.grey))),
            actions: <Widget>[
              IconButton(
                icon: Icon(Icons.search, color: red800), onPressed: () {},),
              IconButton(icon: Icon(Icons.notifications, color: red800),
                onPressed: () {},)
            ],
          ),
        )

      ],
    );
  }

Answer 3

截屏：

代码（空安全）：

为简单起见，我没有创建所需的 UI，我只是想向您展示如何使用以下命令创建自定义应用程序栏PreferredSize

创建这个类：

class CustomAppBar extends StatelessWidget implements PreferredSizeWidget {
  final Widget child;
  final double height;

  CustomAppBar({
    required this.child,
    this.height = kToolbarHeight,
  });

  @override
  Size get preferredSize => Size.fromHeight(height);

  @override
  Widget build(BuildContext context) {
    return Container(
      height: preferredSize.height,
      color: Colors.orange,
      alignment: Alignment.center,
      child: child,
    );
  }
}

用法：

像其他任何一样使用它，AppBar但这次您可以设置height属性：

Scaffold(
  appBar: CustomAppBar(
    height: 120,
    child: Column(
      children: [
        Text('One'),
        Text('Two'),
        Text('Three'),
        Text('Four'),
      ],
    ),
  ),
)

Answer 4

正如我在评论中提到的,你可以像你的Image一样创建一个Custom小部件,有很多方法可以做到,这只是一个例子:

    class CustomBarWidget extends StatelessWidget {

      GlobalKey<ScaffoldState> _scaffoldKey = GlobalKey();

      @override
      Widget build(BuildContext context) {
        return Scaffold(
          key: _scaffoldKey,
          body: Container(
            height: 160.0,
            child: Stack(
              children: <Widget>[
                Container(
                  color: Colors.red,
                  width: MediaQuery.of(context).size.width,
                  height: 100.0,
                  child: Center(
                    child: Text(
                      "Home",
                      style: TextStyle(color: Colors.white, fontSize: 18.0),
                    ),
                  ),
                ),
                Positioned(
                  top: 80.0,
                  left: 0.0,
                  right: 0.0,
                  child: Container(
                    padding: EdgeInsets.symmetric(horizontal: 20.0),
                    child: DecoratedBox(
                      decoration: BoxDecoration(
                          borderRadius: BorderRadius.circular(1.0),
                          border: Border.all(
                              color: Colors.grey.withOpacity(0.5), width: 1.0),
                          color: Colors.white),
                      child: Row(
                        children: [
                          IconButton(
                            icon: Icon(
                              Icons.menu,
                              color: Colors.red,
                            ),
                            onPressed: () {
                              print("your menu action here");
                              _scaffoldKey.currentState.openDrawer();
                            },
                          ),
                          Expanded(
                            child: TextField(
                              decoration: InputDecoration(
                                hintText: "Search",
                              ),
                            ),
                          ),
                          IconButton(
                            icon: Icon(
                              Icons.search,
                              color: Colors.red,
                            ),
                            onPressed: () {
                              print("your menu action here");
                            },
                          ),
                          IconButton(
                            icon: Icon(
                              Icons.notifications,
                              color: Colors.red,
                            ),
                            onPressed: () {
                              print("your menu action here");
                            },
                          ),
                        ],
                      ),
                    ),
                  ),
                )
              ],
            ),
          ),
        );
      }
    }