Flutter 底部导航点击时,颤振弹出至根部
我想实现这样一个功能,当用户点击Flutter 底部导航点击时,颤振弹出至根部,flutter,Flutter,我想实现这样一个功能,当用户点击BottomNavigationBarItem时,如果当前页面索引等于点击的索引,就像普通的iOS应用程序一样,则弹出到根目录。 我试着像下面那样。我将MaterialApp中的所有根页面路由设置为index,popintil到根页面,如果currentIndex等于。 然而错误说 颤振:处理手势时抛出以下状态错误: 颤振:不良状态:未来已完成 我怎样才能做到这一点 代码: // MyApp class class MyApp extends State
BottomNavigationBarItem
时,如果当前页面索引等于点击的索引,就像普通的iOS应用程序一样,则弹出到根目录。
我试着像下面那样。我将MaterialApp
中的所有根页面路由设置为index
,popintil
到根页面,如果currentIndex
等于。
然而错误说
颤振:处理手势时抛出以下状态错误:
颤振:不良状态:未来已完成
我怎样才能做到这一点
代码:
// MyApp class
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new MaterialApp(
routes: <String, WidgetBuilder>{
'/Page1': (BuildContext context) => new Page1(),
'/Page2': (BuildContext context) => new Page2(),
'/Page3': (BuildContext context) => new Page3(),
'/Page4': (BuildContext context) => new Page4(),
},
title: 'Flutter Example',
home: new HomeScreen(),
);
}
}
// MyHome class
class HomeScreen extends StatefulWidget {
@override
_HomeScreenState createState() => new _HomeScreenState();
}
class _HomeScreenState extends State<HomeScreen> {
final List<StatelessWidget> pages = [
new Page1(),
new Page2(),
new Page3(),
new Page3(),
];
final List<String> routes = [
'/Page1',
'/Page2',
'/Page3',
'/Page4',
];
int currentIndex = 0;
@override
Widget build(BuildContext context) {
return new WillPopScope(
onWillPop: () => new Future<bool>.value(true),
child: new CupertinoTabScaffold(
tabBar: new CupertinoTabBar(
onTap: (index) {
if (index == currentIndex) {
Navigator.popUntil(context, ModalRoute.withName(routes[index]));
}
currentIndex = index;
},
backgroundColor: Colors.white,
activeColor: Colors.blue,
inactiveColor: Colors.grey,
items: const <BottomNavigationBarItem>[
BottomNavigationBarItem(
icon: Icon(Icons.looks_one),
title: Text('Page1'),
),
BottomNavigationBarItem(
icon: Icon(Icons.looks_two),
title: Text('Page2'),
),
BottomNavigationBarItem(
icon: Icon(Icons.looks_3),
title: Text('Page3'),
),
BottomNavigationBarItem(
icon: Icon(Icons.looks_4),
title: Text('Page4'),
),
],
),
tabBuilder: (BuildContext context, int index) {
return new DefaultTextStyle(
style: const TextStyle(
fontFamily: '.SF UI Text',
fontSize: 17.0,
color: CupertinoColors.black,
),
child: new CupertinoTabView(
builder: (BuildContext context) {
return pages[index];
},
),
);
},
),
);
}
}
//MyApp类
类MyApp扩展了无状态小部件{
@凌驾
小部件构建(构建上下文){
返回新材料PP(
路线:{
“/Page1”:(BuildContext上下文)=>new Page1(),
“/Page2”:(BuildContext上下文)=>new Page2(),
“/Page3”:(BuildContext上下文)=>new Page3(),
“/Page4”:(BuildContext上下文)=>new Page4(),
},
标题:“颤振示例”,
主页:新的主屏幕(),
);
}
}
//我的家庭课
类主屏幕扩展StatefulWidget{
@凌驾
_HomeScreenState createState()=>新的_HomeScreenState();
}
类_homescrenstate扩展状态{
最终列表页=[
新建页面1(),
新建页面2(),
新建第3页(),
新建第3页(),
];
最终列表路线=[
“/Page1”,
“/Page2”,
“/Page3”,
“/Page4”,
];
int currentIndex=0;
@凌驾
小部件构建(构建上下文){
返回新的Willposcope(
onWillPop:()=>新的未来值(true),
孩子:新杯子(
tabBar:新的CupertinoTabBar(
onTap:(索引){
如果(索引==当前索引){
Navigator.popintil(context,ModalRoute.withName(routes[index]));
}
currentIndex=索引;
},
背景颜色:Colors.white,
activeColor:Colors.blue,
不活动颜色:颜色。灰色,
项目:常数[
底部导航气压计(
图标:图标(图标。看起来像一个图标),
标题:文本(“第1页”),
),
底部导航气压计(
图标:图标(图标。看起来像两个),
标题:文本(“第2页”),
),
底部导航气压计(
图标:图标(图标3),
标题:文本(“第3页”),
),
底部导航气压计(
图标:图标(图标外观4),
标题:文本(“第4页”),
),
],
),
tabBuilder:(BuildContext,int-index){
返回新的DefaultTextStyle(
样式:consttextstyle(
fontFamily:“.SF UI文本”,
字体大小:17.0,
颜色:铜色。黑色,
),
孩子:新Cupertinobview(
生成器:(BuildContext上下文){
返回页[索引];
},
),
);
},
),
);
}
}
如果我正确理解您的需求,您可以使用按钮和移动按钮来达到相同的效果
final PageRouteBuilder\u homeRoute=new PageRouteBuilder(
pageBuilder:(构建上下文上下文,u,u){
返回主屏幕();
},
);
void_goHome(){
Navigator.pushandremoveintil(上下文,_homeRoute,(Route r)=>false);
}
这还可以利用PageRouteBuilder的其他属性。现在可以实现此功能,因为Flatter v1.1.1将navigatorKey添加到CupertinobView中
()
首先,必须为每个选项卡声明一个GlobalKey
,然后将其传递给相应的cupertinobview
构造函数。
然后,在cupertinotabar
的onTap
方法中,如果用户在同一选项卡中点击,则可以使用firstTabNavKey.currentState.popUntil((r)=>r.isFirst)
,并弹出到root
完整示例如下:
void main() {
runApp(MyApp());
}
class MyApp extends StatefulWidget {
@override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
int currentIndex = 0;
final GlobalKey<NavigatorState> firstTabNavKey = GlobalKey<NavigatorState>();
final GlobalKey<NavigatorState> secondTabNavKey = GlobalKey<NavigatorState>();
final GlobalKey<NavigatorState> thirdTabNavKey = GlobalKey<NavigatorState>();
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'My App',
home: CupertinoTabScaffold(
tabBuilder: (BuildContext context, int index) {
switch (index) {
case 0:
return CupertinoTabView(
navigatorKey: firstTabNavKey,
builder: (BuildContext context) => FirstTab(),
);
break;
case 1:
return CupertinoTabView(
navigatorKey: secondTabNavKey,
builder: (BuildContext context) => SecondTab(),
);
break;
case 2:
return CupertinoTabView(
navigatorKey: thirdTabNavKey,
builder: (BuildContext context) => ThirdTab(),
);
break;
}
return null;
},
tabBar: CupertinoTabBar(
items: <BottomNavigationBarItem> [
BottomNavigationBarItem(
title: Text('Tab 1'),
),
BottomNavigationBarItem(
title: Text('Tab 2'),
),
BottomNavigationBarItem(
title: Text('Tab 3'),
),
],
onTap: (index){
// back home only if not switching tab
if(currentIndex == index) {
switch (index) {
case 0:
firstTabNavKey.currentState.popUntil((r) => r.isFirst);
break;
case 1:
secondTabNavKey.currentState.popUntil((r) => r.isFirst);
break;
case 2:
thirdTabNavKey.currentState.popUntil((r) => r.isFirst);
break;
}
}
currentIndex = index;
},
),
),
);
}
}
void main(){
runApp(MyApp());
}
类MyApp扩展了StatefulWidget{
@凌驾
_MyAppState createState()=>\u MyAppState();
}
类MyAppState扩展了状态{
int currentIndex=0;
final GlobalKey firstTabNavKey=GlobalKey();
最终GlobalKey secondTabNavKey=GlobalKey();
最终GlobalKey thirdTabNavKey=GlobalKey();
@凌驾
小部件构建(构建上下文){
返回材料PP(
标题:“我的应用程序”,
住家:库珀蒂诺巴塞弗德(
tabBuilder:(BuildContext,int-index){
开关(索引){
案例0:
返回CupertinoTabView(
navigatorKey:firstTabNavKey,
生成器:(BuildContext上下文)=>FirstTab(),
);
打破
案例1:
返回CupertinoTabView(
导航工作:第二个TabNavKey,
生成器:(BuildContext上下文)=>SecondTab(),
);
打破
案例2:
返回CupertinoTabView(
导航工作:第三个ABNAVKEY,
生成器:(BuildContext上下文)=>ThirdTab(),
);
打破
}
返回null;
},
tabBar:CupertinoTabBar(
项目:[
底部导航气压计(
标题:文本(“表1”),
),
底部导航气压计(
标题:文本(“表2”),
),
底部导航气压计(
标题:文本(“表3”),
),
],
onTap:(索引){
//仅当不切换选项卡时返回主页
void main() {
runApp(MyApp());
}
class MyApp extends StatefulWidget {
@override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
int currentIndex = 0;
final GlobalKey<NavigatorState> firstTabNavKey = GlobalKey<NavigatorState>();
final GlobalKey<NavigatorState> secondTabNavKey = GlobalKey<NavigatorState>();
final GlobalKey<NavigatorState> thirdTabNavKey = GlobalKey<NavigatorState>();
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'My App',
home: CupertinoTabScaffold(
tabBuilder: (BuildContext context, int index) {
switch (index) {
case 0:
return CupertinoTabView(
navigatorKey: firstTabNavKey,
builder: (BuildContext context) => FirstTab(),
);
break;
case 1:
return CupertinoTabView(
navigatorKey: secondTabNavKey,
builder: (BuildContext context) => SecondTab(),
);
break;
case 2:
return CupertinoTabView(
navigatorKey: thirdTabNavKey,
builder: (BuildContext context) => ThirdTab(),
);
break;
}
return null;
},
tabBar: CupertinoTabBar(
items: <BottomNavigationBarItem> [
BottomNavigationBarItem(
title: Text('Tab 1'),
),
BottomNavigationBarItem(
title: Text('Tab 2'),
),
BottomNavigationBarItem(
title: Text('Tab 3'),
),
],
onTap: (index){
// back home only if not switching tab
if(currentIndex == index) {
switch (index) {
case 0:
firstTabNavKey.currentState.popUntil((r) => r.isFirst);
break;
case 1:
secondTabNavKey.currentState.popUntil((r) => r.isFirst);
break;
case 2:
thirdTabNavKey.currentState.popUntil((r) => r.isFirst);
break;
}
}
currentIndex = index;
},
),
),
);
}
}
onPressed: () {
Navigator.of(context).pushNamedAndRemoveUntil('/', ModalRoute.withName('/'));
}