Loader is stuck and doesn't navigate to next page

I have implemented a loader from flutter_spinkit package, the loader appears when users navigate to another page through the navigation drawer, the problem is when user clicks the button that navigate to another page the loader appears and stuck without closing or navigating, here is the code :

onTap: () async {
                //Close the navigation Drawer
                Navigator.pop(context);

                //Show dialog that contains the loader
                showDialog(
                  context: context,
                  barrierDismissible: false,
                  builder: (BuildContext context) {
                    return WillPopScope(
                      onWillPop: () async {
                        return false;
                      },
                      child: SpinKitCircle(
                        color: Colors.purple,
                        size: 50.0,
                      ),
                    );
                  },
                );

                //Close the Loader Dialog after 3 seconds (it doesn't close)
                await Future.delayed(Duration(seconds: 3), () {
                  Navigator.pop(context);
                });
                
                //Navigate to the next page 
                Navigator.push(
                  context,
                  MaterialPageRoute(
                    builder: (context) => const MyChallenges(),
                  ),
                );
              },

Console is showing this :

E/flutter ( 6263): [ERROR:flutter/lib/ui/ui_dart_state.cc(198)] Unhandled Exception: Null check operator used on a null value
E/flutter ( 6263): #0      StatefulElement.state
package:flutter/…/widgets/framework.dart:4926
E/flutter ( 6263): #1      Navigator.of
package:flutter/…/widgets/navigator.dart:2542
E/flutter ( 6263): #2      Navigator.pop
package:flutter/…/widgets/navigator.dart:2432
E/flutter ( 6263): #3      _NavigationDrawerState.buildMenuItems.<anonymous closure>.<anonymous closure>
package:athaddakapp/screens/navigation_drawer.dart:123
E/flutter ( 6263): #4      new Future.delayed.<anonymous closure> (dart:async/future.dart:423:39)
E/flutter ( 6263): #5      _rootRun (dart:async/zone.dart:1418:47)
E/flutter ( 6263): #6      _CustomZone.run (dart:async/zone.dart:1328:19)
E/flutter ( 6263): #7      _CustomZone.runGuarded (dart:async/zone.dart:1236:7)
E/flutter ( 6263): #8      _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:1276:23)
E/flutter ( 6263): #9      _rootRun (dart:async/zone.dart:1426:13)
E/flutter ( 6263): #10     _CustomZone.run (dart:async/zone.dart:1328:19)
E/flutter ( 6263): #11     _CustomZone.bindCallback.<anonymous closure> (dart:async/zone.dart:1260:23)
E/flutter ( 6263): #12     Timer._createTimer.<anonymous closure> (dart:async-patch/timer_patch.dart:18:15)
E/flutter ( 6263): #13     _Timer._runTimers (dart:isolate-patch/timer_impl.dart:398:19)
E/flutter ( 6263): #14     _Timer._handleMessage (dart:isolate-patch/timer_impl.dart:429:5)
E/flutter ( 6263): #15     _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:192:12)

the loader keeps loads and doesn't navigate, ill appreciate any idea. Thank you

CodePudding user response：

Try to use global key in main for context in showDialog and Navigator.pop which is used to close the dialog

CodePudding user response：

Use main widget context to navigate.

Simply change showDialog context name

builder: (BuildContext dialogContext) { or builder: (_) {