Flutter:使用不同的数据和后退按钮刷新同一屏幕
Flutter : Refresh same screen with different data and back button
几天前我最近开始探索 Flutter。我创建了一个包含一些行的列表。
有些行有子数据。
现在屏幕顶部有自定义按钮。
final topAppBar = AppBar(
elevation: 0.1,
backgroundColor: Color.fromRGBO(0, 113, 188, 1.0),
title: Text("RESOURCES", style: TextStyle(
color: Colors.white,
fontFamily: 'Raleway-ExtraBold',
fontWeight: FontWeight.w900,
fontSize: 20.0,
),),
leading: IconButton(
icon: new Image.asset('assets/images/settings.png'),
),
);
当用户点击这些行时,我只想用子数据刷新列表,并通过更新顶部的“后退按钮”来推送效果。
下面的代码能够通过推送效果在屏幕上导航,但是我们如何使用数据和后退按钮来维护应用程序的状态。
ListTile makeResourcesListTile(Resources resources) => ListTile(
contentPadding: EdgeInsets.symmetric(horizontal: 20.0, vertical: 0.0),
title: Text(
resources.title,
style: TextStyle(
color: Colors.white,
fontSize: 14.0,
fontWeight: FontWeight.bold,
fontFamily: "Raleway-Bold",
),
),
trailing:
Icon(Icons.keyboard_arrow_right, color: Colors.white, size: 30.0),
onTap: () {
Navigator.pushNamed(context, ‘/listScreen’);
},
);
求推荐。提前谢谢你
我想你应该看看:
这是您要找的吗?
LE:
如果您只想更改列表的数据源并添加后退按钮,请尝试以下代码:
class MyHomePage extends StatefulWidget {
@override
State<StatefulWidget> createState() {
return _MyHomePageState();
}
}
class _MyHomePageState extends State<MyHomePage> {
bool showDetails = false;
String title = 'Resources';
List<Resource> resources = [
new Resource('1', 'one', null),
new Resource('2', 'two', [new Resource('Child', 'Child', null)]),
new Resource('3', 'three', null),
new Resource('4', 'four', [
new Resource('Child', 'Child', null),
new Resource('Child', 'Child', null)
]),
new Resource('5', 'five', null)
];
List<Resource> currentSource;
@override
Widget build(BuildContext context) {
if (!showDetails) {
currentSource = resources;
}
Widget showResourcesList() {
return new ListView.builder(
itemCount: currentSource.length,
itemBuilder: (BuildContext context, int index) {
return new ListTile(
title: Center(
child: Text(currentSource[index].name),
),
onTap: () {
setState(() {
if (currentSource[index].children != null) {
title = 'Children for ' + currentSource[index].name;
currentSource = resources[index].children;
showDetails = true;
}
});
});
});
}
Widget showBackButton() {
return IconButton(
icon: Icon(Icons.arrow_back),
onPressed: () {
setState(() {
showDetails = false;
currentSource = resources;
title = 'Resources';
});
},
);
}
Widget showSettingsButton() {
return IconButton(
icon: Icon(Icons.settings),
onPressed: () {},
);
}
return Scaffold(
appBar: AppBar(
elevation: 0.1,
backgroundColor: Color.fromRGBO(0, 113, 188, 1.0),
title: Text(
title,
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.w900,
fontSize: 20.0,
),
),
leading: showDetails ? showBackButton() : showSettingsButton(),
),
body: showResourcesList(),
);
}
}
class Resource {
String name;
String description;
List<Resource> children;
Resource(this.name, this.description, this.children);
}
我使用了代表应用程序状态的 bool 变量 (showDetails),并且在点击 listTile 时更改了数据源。
几天前我最近开始探索 Flutter。我创建了一个包含一些行的列表。 有些行有子数据。
现在屏幕顶部有自定义按钮。
final topAppBar = AppBar(
elevation: 0.1,
backgroundColor: Color.fromRGBO(0, 113, 188, 1.0),
title: Text("RESOURCES", style: TextStyle(
color: Colors.white,
fontFamily: 'Raleway-ExtraBold',
fontWeight: FontWeight.w900,
fontSize: 20.0,
),),
leading: IconButton(
icon: new Image.asset('assets/images/settings.png'),
),
);
当用户点击这些行时,我只想用子数据刷新列表,并通过更新顶部的“后退按钮”来推送效果。
下面的代码能够通过推送效果在屏幕上导航,但是我们如何使用数据和后退按钮来维护应用程序的状态。
ListTile makeResourcesListTile(Resources resources) => ListTile(
contentPadding: EdgeInsets.symmetric(horizontal: 20.0, vertical: 0.0),
title: Text(
resources.title,
style: TextStyle(
color: Colors.white,
fontSize: 14.0,
fontWeight: FontWeight.bold,
fontFamily: "Raleway-Bold",
),
),
trailing:
Icon(Icons.keyboard_arrow_right, color: Colors.white, size: 30.0),
onTap: () {
Navigator.pushNamed(context, ‘/listScreen’);
},
);
求推荐。提前谢谢你
我想你应该看看:
这是您要找的吗?
LE:
如果您只想更改列表的数据源并添加后退按钮,请尝试以下代码:
class MyHomePage extends StatefulWidget {
@override
State<StatefulWidget> createState() {
return _MyHomePageState();
}
}
class _MyHomePageState extends State<MyHomePage> {
bool showDetails = false;
String title = 'Resources';
List<Resource> resources = [
new Resource('1', 'one', null),
new Resource('2', 'two', [new Resource('Child', 'Child', null)]),
new Resource('3', 'three', null),
new Resource('4', 'four', [
new Resource('Child', 'Child', null),
new Resource('Child', 'Child', null)
]),
new Resource('5', 'five', null)
];
List<Resource> currentSource;
@override
Widget build(BuildContext context) {
if (!showDetails) {
currentSource = resources;
}
Widget showResourcesList() {
return new ListView.builder(
itemCount: currentSource.length,
itemBuilder: (BuildContext context, int index) {
return new ListTile(
title: Center(
child: Text(currentSource[index].name),
),
onTap: () {
setState(() {
if (currentSource[index].children != null) {
title = 'Children for ' + currentSource[index].name;
currentSource = resources[index].children;
showDetails = true;
}
});
});
});
}
Widget showBackButton() {
return IconButton(
icon: Icon(Icons.arrow_back),
onPressed: () {
setState(() {
showDetails = false;
currentSource = resources;
title = 'Resources';
});
},
);
}
Widget showSettingsButton() {
return IconButton(
icon: Icon(Icons.settings),
onPressed: () {},
);
}
return Scaffold(
appBar: AppBar(
elevation: 0.1,
backgroundColor: Color.fromRGBO(0, 113, 188, 1.0),
title: Text(
title,
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.w900,
fontSize: 20.0,
),
),
leading: showDetails ? showBackButton() : showSettingsButton(),
),
body: showResourcesList(),
);
}
}
class Resource {
String name;
String description;
List<Resource> children;
Resource(this.name, this.description, this.children);
}
我使用了代表应用程序状态的 bool 变量 (showDetails),并且在点击 listTile 时更改了数据源。