How to implement a Custom dialog box in flutter?

Solution 1:

Use Dialog class which is a parent class to AlertDialog class in Flutter. Dialog widget has a argument , "shape" which you can use to shape the Edges of the Dialog box.

Here is a code sample:

 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)),
        TextButton(onPressed: () {
          Navigator.of(context).pop();
        },
            child: Text('Got It!', style: TextStyle(color: Colors.purple, fontSize: 18.0),))
      ],
    ),
  ),
);
showDialog(context: context, builder: (BuildContext context) => errorDialog);}

Solution 2:

Screenshot (Null Safe):

Code:

Just call this method:

void showCustomDialog(BuildContext context) {
  showGeneralDialog(
    context: context,
    barrierLabel: "Barrier",
    barrierDismissible: true,
    barrierColor: Colors.black.withOpacity(0.5),
    transitionDuration: Duration(milliseconds: 700),
    pageBuilder: (_, __, ___) {
      return Center(
        child: Container(
          height: 240,
          child: SizedBox.expand(child: FlutterLogo()),
          margin: EdgeInsets.symmetric(horizontal: 20),
          decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(40)),
        ),
      );
    },
    transitionBuilder: (_, anim, __, child) {
      Tween<Offset> tween;
      if (anim.status == AnimationStatus.reverse) {
        tween = Tween(begin: Offset(-1, 0), end: Offset.zero);
      } else {
        tween = Tween(begin: Offset(1, 0), end: Offset.zero);
      }
  
      return SlideTransition(
        position: tween.animate(anim),
        child: FadeTransition(
          opacity: anim,
          child: child,
        ),
      );
    },
  );
}

Solution 3:

On a button click show dialog as -

showDialog(
        context: context,
        builder: (_) => LogoutOverlay(),
      );

Dialog design with two buttons -

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);
                                   */ });
                                  },
                                ))
                          ),
                        ],
                      ))
                    ],
                  )),
            ),
          ),
        );
      }
    }

Solution 4:

You just put this class in your project and call its method for showing dialog.
Using this class you don't need to write dialog code everywhere

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))
            ],
          );
        });
  }
 }

You can call this method like :

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(),
)