FlutterのAlertDialogクラスの親クラスであるDialogクラスを使用します。ダイアログウィジェットには、ダイアログボックスのエッジを整形するために使用できる引数 "shape"があります。
コードサンプルは次のとおりです。
Dialog errorDialog = Dialog(
shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12.0)), //this right here
child: Container(
height: 300.0,
width: 300.0,
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Padding(
padding: EdgeInsets.all(15.0),
child: Text('Cool', style: TextStyle(color: Colors.red),),
),
Padding(
padding: EdgeInsets.all(15.0),
child: Text('Awesome', style: TextStyle(color: Colors.red),),
),
Padding(padding: EdgeInsets.only(top: 50.0)),
FlatButton(onPressed: (){
Navigator.of(context).pop();
},
child: Text('Got It!', style: TextStyle(color: Colors.purple, fontSize: 18.0),))
],
),
),
);
showDialog(context: context, builder: (BuildContext context) => errorDialog);}
ボタンで[ダイアログを表示]をクリックします-
showDialog(
context: context,
builder: (_) => LogoutOverlay(),
);
2つのボタンを持つダイアログデザイン-
class LogoutOverlay extends StatefulWidget {
@override
State<StatefulWidget> createState() => LogoutOverlayState();
}
class LogoutOverlayState extends State<LogoutOverlay>
with SingleTickerProviderStateMixin {
AnimationController controller;
Animation<double> scaleAnimation;
@override
void initState() {
super.initState();
controller =
AnimationController(vsync: this, duration: Duration(milliseconds: 450));
scaleAnimation =
CurvedAnimation(parent: controller, curve: Curves.elasticInOut);
controller.addListener(() {
setState(() {});
});
controller.forward();
}
@override
Widget build(BuildContext context) {
return Center(
child: Material(
color: Colors.transparent,
child: ScaleTransition(
scale: scaleAnimation,
child: Container(
margin: EdgeInsets.all(20.0),
padding: EdgeInsets.all(15.0),
height: 180.0,
decoration: ShapeDecoration(
color: Color.fromRGBO(41, 167, 77, 10),
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(15.0))),
child: Column(
children: <Widget>[
Expanded(
child: Padding(
padding: const EdgeInsets.only(
top: 30.0, left: 20.0, right: 20.0),
child: Text(
"Are you sure, you want to logout?",
style: TextStyle(color: Colors.white, fontSize: 16.0),
),
)),
Expanded(
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Padding(
padding: const EdgeInsets.all(10.0),
child: ButtonTheme(
height: 35.0,
minWidth: 110.0,
child: RaisedButton(
color: Colors.white,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(5.0)),
splashColor: Colors.white.withAlpha(40),
child: Text(
'Logout',
textAlign: TextAlign.center,
style: TextStyle(
color: Colors.green,
fontWeight: FontWeight.bold,
fontSize: 13.0),
),
onPressed: () {
setState(() {
Route route = MaterialPageRoute(
builder: (context) => LoginScreen());
Navigator.pushReplacement(context, route);
});
},
)),
),
Padding(
padding: const EdgeInsets.only(
left: 20.0, right: 10.0, top: 10.0, bottom: 10.0),
child: ButtonTheme(
height: 35.0,
minWidth: 110.0,
child: RaisedButton(
color: Colors.white,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(5.0)),
splashColor: Colors.white.withAlpha(40),
child: Text(
'Cancel',
textAlign: TextAlign.center,
style: TextStyle(
color: Colors.green,
fontWeight: FontWeight.bold,
fontSize: 13.0),
),
onPressed: () {
setState(() {
/* Route route = MaterialPageRoute(
builder: (context) => LoginScreen());
Navigator.pushReplacement(context, route);
*/ });
},
))
),
],
))
],
)),
),
),
);
}
}
一般的な例
showDialog(context: context,builder: (context) => _onTapImage(context)); // Call the Dialog.
_onTapImage(BuildContext context) {
return Stack(
alignment: Alignment.center,
children: <Widget>[
Image.network('https://via.placeholder.com/150',fit: BoxFit.contain,), // Show your Image
Align(
alignment: Alignment.topRight,
child: RaisedButton.icon(
color: Theme.of(context).accentColor,
textColor: Colors.white,
onPressed: () => Navigator.pop(context),
icon: Icon(
Icons.close,
color: Colors.white,
),
label: Text('Close')),
),
],
);
}
このクラスをプロジェクトに配置し、ダイアログを表示するためにそのメソッドを呼び出すだけです。
このクラスを使用すると、どこにでもダイアログコードを記述する必要はありません。
class DialogUtils {
static DialogUtils _instance = new DialogUtils.internal();
DialogUtils.internal();
factory DialogUtils() => _instance;
static void showCustomDialog(BuildContext context,
{@required String title,
String okBtnText = "Ok",
String cancelBtnText = "Cancel",
@required Function okBtnFunction}) {
showDialog(
context: context,
builder: (_) {
return AlertDialog(
title: Text(title),
content: /* Here add your custom widget */,
actions: <Widget>[
FlatButton(
child: Text(okBtnText),
onPressed: okBtnFunction,
),
FlatButton(
child: Text(cancelBtnText),
onPressed: () => Navigator.pop(context))
],
);
});
}
}
このメソッドは次のように呼び出すことができます。
GestureDetector(
onTap: () =>
DialogUtils.showCustomDialog(context,
title: "Gallary",
okBtnText: "Save",
cancelBtnText: "Cancel",
okBtnFunction: () => /* call method in which you have write your logic and save process */),
child: Container(),
)