我想在单击抽屉项时显示AlertDialog
我正在使用以下代码在我的Flutter应用中使用导航抽屉项目
class HomePage extends StatefulWidget {
final drawerItems = [
DrawerItem("View Your account", Icons.account_circle),
DrawerItem("Request", Icons.receipt),
DrawerItem("Order", Icons.shopping_cart),
DrawerItem("Report", Icons.report_problem),
DrawerItem("Log out", Icons.info)
];
@override
State<StatefulWidget> createState() {
return new HomePageState();
}
}
class HomePageState extends State<HomePage> {
int _selectedDrawerIndex = 0;
bool visibilityTag = false;
showAlertDialog(BuildContext context) {
// set up the button
Widget okButton = FlatButton(
child: Text("OK"),
onPressed: () {
Navigator.of(context).pop();
},
);
Widget cancelButton = FlatButton(
child: Text("Cancel"),
onPressed: () {
Navigator.of(context).pop();
},
);
// set up the AlertDialog
AlertDialog alert = AlertDialog(
elevation: 10,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.all(Radius.circular(20.0))),
title: Text("ORICON"),
content: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Text("Are you sure you want to logout?"),
Padding(
padding: const EdgeInsets.only(top: 20.0),
child: Text(
"1300 898 989",
style: TextStyle(
color: Colors.blue,
fontWeight: FontWeight.bold,
fontSize: 20.0),
),
),
],
),
actions: [okButton, cancelButton],
);
showDialog(
context: context,
barrierDismissible: false,
builder: (BuildContext context) {
return alert;
},
);
}
_getDrawerItemWidget(int pos) {
switch (pos) {
case 0:
visibilityTag = false;
return AccountDetails();
case 1:
visibilityTag = true;
return RequestBin();
case 2:
visibilityTag = true;
return OrderBin();
case 3:
visibilityTag = true;
return Report();
case 4:
showAlertDialog(context);
visibilityTag = false;
return AccountDetails();
default:
return new Text("Error");
}
}
_onSelectItem(int index) {
if (index == 0) {
visibilityTag = false;
} else {
visibilityTag = true;
}
// setState(() => _selectedDrawerIndex = index);
_selectedDrawerIndex = index; // removed setState call
Navigator.of(context).pop(); // close the drawer
}
@override
Widget build(BuildContext context) {
List<Widget> drawerOptions = [];
for (var i = 0; i < widget.drawerItems.length; i++) {
var d = widget.drawerItems[i];
drawerOptions.add(new ListTile(
leading: Icon(d.icon),
title: Text(d.title),
selected: i == _selectedDrawerIndex,
onTap: () => _onSelectItem(i),
));
}
Future<bool> customPop() {
if (_selectedDrawerIndex == 0) {
visibilityTag = false;
return Future.value(true);
} else {
setState(() {
visibilityTag = false;
_selectedDrawerIndex = 0;
});
return Future.value(false);
}
}
void navigateToHomeScreen() {
if (_selectedDrawerIndex == 0) {
visibilityTag = false;
} else {
visibilityTag = false;
setState(() {
_selectedDrawerIndex = 0;
});
}
}
return WillPopScope(
onWillPop: customPop,
child: Scaffold(
appBar: AppBar(
backgroundColor: Colors.white,
iconTheme: IconThemeData(color: Colors.black), //add this line here
// here we display the title corresponding to the fragment
// you can instead choose to have a static title
title: Text(
widget.drawerItems[_selectedDrawerIndex].title,
style: TextStyle(color: Colors.black),
),
actions: <Widget>[
Padding(
padding: const EdgeInsets.only(right: 10),
child: Visibility(
visible: visibilityTag,
child: Row(
children: <Widget>[
IconButton(
icon: new Icon(Icons.arrow_back_ios),
color: Colors.grey,
onPressed: navigateToHomeScreen,
),
Text(
"BACK",
style: TextStyle(color: Colors.grey),
)
],
)),
)
],
),
drawer: Drawer(
child: Column(
children: <Widget>[
UserAccountsDrawerHeader(
accountName: new Text("Nilesh Rathod"), accountEmail: null),
Column(children: drawerOptions)
],
),
),
body: _getDrawerItemWidget(_selectedDrawerIndex)),
);
}
}
但是我在例外之下
This Overlay widget cannot be marked as needing to build because the framework is already in the process of building widgets. A widget can be marked as needing to be built during the build phase only if one of its ancestors is currently building. This exception is allowed because the framework builds parent widgets before children, which means a dirty descendant will always be built. Otherwise, the framework might not visit this widget during this build phase.
The widget on which setState() or markNeedsBuild() was called was: Overlay-[LabeledGlobalKey<OverlayState>#7e1a8]
state: OverlayState#72b8b(entries: [OverlayEntry#cf40a(opaque: false; maintainState: false), OverlayEntry#e10aa(opaque: false; maintainState: true), OverlayEntry#e0ccc(opaque: false; maintainState: false), OverlayEntry#5fdab(opaque: false; maintainState: true)])
The widget which was currently being built when the offending call was made was: HomePage
dirty
dependencies: [_InheritedTheme, _LocalizationsScope-[GlobalKey#c84d4]]
state: HomePageState#982b0
User-created ancestor of the error-causing widget was:
MaterialApp file:///home/ctpl119/Documents/NEW_PROJECT/oricon/oricon/lib/main.dart:11:10
When the exception was thrown, this was the stack:
#0 Element.markNeedsBuild.<anonymous closure> (package:flutter/src/widgets/framework.dart:3687:11)
#1 Element.markNeedsBuild (package:flutter/src/widgets/framework.dart:3702:6)
#2 State.setState (package:flutter/src/widgets/framework.dart:1161:14)
#3 OverlayState.insertAll (package:flutter/src/widgets/overlay.dart:346:5)
#4 OverlayRoute.install (package:flutter/src/widgets/routes.dart:43:24)
我已经检查了下面的堆栈溢出链接
如果需要更多信息，请告诉我。提前致谢。您的努力将不胜感激。