UNIRest: switch to a new ViewController on an Asynchronous HTTP response - ios

Question

I'm using the UNIRest library and I'm trying to switch to another ViewController on the response of an HTTP GET method.
[[UNIRest get:^(UNISimpleRequest *request) {
[request setUrl:GEtFamilyMembers];
}] asJsonAsync:^(UNIHTTPJsonResponse* response, NSError *error) {
NSLog(#"res: %#", response.body);
if (response.code == 200) {
GCHFamilyMembersViewConroller* fmViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"gchFamilyMembers"];
self.navigationController.viewControllers = #[fmViewController];
[self.mm_drawerController setCenterViewController:self.navigationController withCloseAnimation:YES completion:nil];
} else {
[self showToast:#"Something went wrong, Please try again after some time."];
}
}];
Even after printing the response using NSLog. Nothing happens for about 30 seconds. Then suddenly app crashes.
I thought it's because Asynch call blocks UI so I tired a method like:
- (void) gotoSelectFamilyMembers {
dispatch_async(dispatch_get_main_queue(), ^{
GCHFamilyMembersViewConroller* fmViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"gchFamilyMembers"];
self.navigationController.viewControllers = #[fmViewController];
[self.mm_drawerController setCenterViewController:self.navigationController withCloseAnimation:YES completion:nil];
});
}
but still the app crashes.
Earlier when I was using a Synchronous call it was working. But not now.
Please help!
EDIT:
2016-05-02 17:58:22.695 Checkme Mobile[6208:136321] *** Assertion failure in -[UIKeyboardTaskQueue waitUntilAllTasksAreFinished], /SourceCache/UIKit_Sim/UIKit-3347.44.2/Keyboard/UIKeyboardTaskQueue.m:374
2016-05-02 17:58:22.728 Checkme Mobile[6208:136224] NSScanner: nil string argument
2016-05-02 17:58:22.728 Checkme Mobile[6208:136224] NSScanner: nil string argument
2016-05-02 17:58:23.730 Checkme Mobile[6208:136224] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '-[UIKeyboardTaskQueue waitUntilAllTasksAreFinished] may only be called from the main thread.'
*** First throw call stack:
(
0 CoreFoundation 0x00000001094a6c65 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x0000000108da2bb7 objc_exception_throw + 45
2 CoreFoundation 0x00000001094a6aca +[NSException raise:format:arguments:] + 106
3 Foundation 0x00000001089b798f -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 195
4 UIKit 0x0000000107d887d6 -[UIKeyboardTaskQueue waitUntilAllTasksAreFinished] + 151
5 UIKit 0x0000000107829912 -[UIKeyboardImpl setDelegate:force:] + 473
6 UIKit 0x0000000107ad44ad -[UIPeripheralHost(UIKitInternal) _reloadInputViewsForResponder:] + 1002
7 UIKit 0x0000000107adc834 -[UIPeripheralHost(UIKitInternal) _preserveInputViewsWithId:animated:reset:] + 504
8 UIKit 0x000000010778e181 -[UINavigationController navigationTransitionView:didStartTransition:] + 578
9 UIKit 0x00000001079948bc -[UINavigationTransitionView transition:fromView:toView:] + 655
10 UIKit 0x0000000107792170 -[UINavigationController _startTransition:fromViewController:toViewController:] + 2984
11 UIKit 0x0000000107792408 -[UINavigationController _startDeferredTransitionIfNeeded:] + 523
12 UIKit 0x0000000107792ece -[UINavigationController __viewWillLayoutSubviews] + 43
13 UIKit 0x00000001078dd6d5 -[UILayoutContainerView layoutSubviews] + 202
14 UIKit 0x00000001076b09eb -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 536
15 QuartzCore 0x0000000109d83ed2 -[CALayer layoutSublayers] + 146
16 QuartzCore 0x0000000109d786e6 _ZN2CA5Layer16layout_if_neededEPNS_11TransactionE + 380
17 QuartzCore 0x0000000109d78556 _ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE + 24
18 QuartzCore 0x0000000109ce486e _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 242
19 QuartzCore 0x0000000109ce5a22 _ZN2CA11Transaction6commitEv + 462
20 QuartzCore 0x0000000109ce5c99 _ZN2CA11Transaction14release_threadEPv + 199
21 libsystem_pthread.dylib 0x000000010a35172a _pthread_tsd_cleanup + 86
22 libsystem_pthread.dylib 0x000000010a351451 _pthread_exit + 117
23 libsystem_pthread.dylib 0x000000010a3506cd _pthread_wqthread + 879
24 libsystem_pthread.dylib 0x000000010a34e40d start_wqthread + 13
)
2016-05-02 17:58:23.730 Checkme Mobile[6208:136321] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '-[UIKeyboardTaskQueue waitUntilAllTasksAreFinished] may only be called from the main thread.'
*** First throw call stack:
(
0 CoreFoundation 0x00000001094a6c65 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x0000000108da2bb7 objc_exception_throw + 45
2 CoreFoundation 0x00000001094a6aca +[NSException raise:format:arguments:] + 106
3 Foundation 0x00000001089b798f -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 195
4 UIKit 0x0000000107d887d6 -[UIKeyboardTaskQueue waitUntilAllTasksAreFinished] + 151
5 UIKit 0x0000000107829912 -[UIKeyboardImpl setDelegate:force:] + 473
6 UIKit 0x0000000107ad44ad -[UIPeripheralHost(UIKitInternal) _reloadInputViewsForResponder:] + 1002
libc++abi.dylib: 7 UIKit 0x0000000107adc834 -[UIPeripheralHost(UIKitInternal) _preserveInputViewsWithId:animated:reset:] + 504
8 UIKit 0x000000010778e181 -[UINavigationController navigationTransitionView:didStartTransition:] + 578
9 UIKit 0x00000001079948bc -[UINavigationTransitionView transition:fromView:toView:] + 655
10 UIKit 0x0000000107792170 -[UINavigationController _startTransition:fromViewController:toViewController:] + 2984
11 UIKit 0x0000000107792408 -[UINavigationController _startDeferredTransitionIfNeeded:] + 523
12 UIKit 0x0000000107792ece -[UINavigationController __viewWillLayoutSubviews] + 43
13 UIKit 0x00000001078dd6d5 -[UILayoutContainerView layoutSubviews] + 202
14 UIKit 0x00000001076b09eb -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 536
15 QuartzCore 0x0000000109d83ed2 -[CALayer layoutSublayers] + 146
16 QuartzCore 0x0000000109d786e6 _ZN2CA5Layer16layout_if_neededEPNS_11TransactionE + 380
17 QuartzCore 0x0000000109d78556 _ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE + 24
18 QuartzCore 0x0000000109ce486e _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 242
19 QuartzCore 0x0000000109ce5a22 _ZN2CA11Transaction6commitEv + 462
20 QuartzCore 0x0000000109ce5c99 _ZN2CA11Transaction14release_threadEPv + 199
21 libsystem_pthread.dylib 0x000000010a35172a _pthread_tsd_cleanup + 86
22 libsystem_pthread.dylib 0x000000010a351451 _pthread_exit + 117
23 libsystem_pthread.dylib 0x000000010a3506cd _pthread_wqthread + 879
24 libsystem_pthread.dylib 0x000000010a34e40d start_wqthread + 13
)
terminating with uncaught exception of type NSExceptionlibc++abi.dylib:
terminating with uncaught exception of type NSException
(lldb)
EDit:
- (IBAction)loginAction:(id)sender {
self.email = usernameTextField.text;
self.password = passwordTextField.text;
if(!([self.email isEqualToString:#""] && [self.password isEqualToString:#""])) {
[self performLogin];
} else{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"error" message:#"Enter both username and password." delegate:nil cancelButtonTitle:#"Ok" otherButtonTitles:nil, nil];
[alert show];
}
}
- (void) performLogin {
NSDictionary* headers = #{#"Content-Type": #"application/x-www-form-urlencoded"};
NSDictionary* parameters = #{#"username": self.email, #"password": self.password};
[[NSThread currentThread] isMainThread] ? NSLog(#"1MAIN THREAD") : NSLog(#"1NOT MAIN THREAD");
self.loginConnection = [[UNIRest post:^(UNISimpleRequest *request) {
[request setUrl:LOgin];
[request setHeaders:headers];
[request setParameters:parameters];
}] asJsonAsync:^(UNIHTTPJsonResponse* response, NSError *error) {
// This is the asyncronous callback block
[[NSThread currentThread] isMainThread] ? NSLog(#"2MAIN THREAD") : NSLog(#"2NOT MAIN THREAD");
UNIJsonNode *body = response.body;
NSData *rawBody = response.rawBody;
NSString *string = [[NSString alloc] initWithData:rawBody encoding:NSUTF8StringEncoding];
NSLog(#"response signup: %#", string);
if (response.code == 200) {
[self processLoginResponse:body];
}
}];
}
- (void) processLoginResponse:(UNIJsonNode *) body {
if ([body.JSONObject[#"status"] boolValue] == YES) {
NSString *firstName = body.JSONObject[#"firstName"];
NSString *lastName = body.JSONObject[#"lastName"];
NSString *name = [firstName stringByAppendingString:lastName];
NSMutableDictionary *mDictionary = [[NSMutableDictionary alloc] init];
[mDictionary setObject:body.JSONObject[#"accountId"] forKey:#"accountId"];
[mDictionary setObject:name forKey:#"name"];
[mDictionary setObject:#"Custodian" forKey:#"relation"];
[self fetchFamilyMembers:mDictionary];
} else {
[self showAlert:body.JSONObject[#"message"]];
}
}
- (void) fetchFamilyMembers:(NSMutableDictionary *) mDictionary {
[[NSThread currentThread] isMainThread] ? NSLog(#"3MAIN THREAD") : NSLog(#"3NOT MAIN THREAD");
self.fmConnection = [[UNIRest get:^(UNISimpleRequest *request) {
[request setUrl:GEtFamilyMembers];
}] asJsonAsync:^(UNIHTTPJsonResponse* response, NSError *error) {
NSLog(#"res: %#", response.body);
if (response.code == 200) {
[[NSThread currentThread] isMainThread] ? NSLog(#"4MAIN THREAD") : NSLog(#"4NOT MAIN THREAD");
NSData *rawBody = response.rawBody;
NSString *string = [[NSString alloc] initWithData:rawBody encoding:NSUTF8StringEncoding];
NSLog(#"family signup: %#", string);
[[NSThread currentThread] isMainThread] ? NSLog(#"5MAIN THREAD") : NSLog(#"5NOT MAIN THREAD");
[self processFamilyMembersResponse:mDictionary :response.body];
} else {
[self showToast:#"Something went wrong, Please try again after some time."];
}
}];
}
- (void) processFamilyMembersResponse:(NSMutableDictionary *) mDictionary :(UNIJsonNode *) body {
NSArray *fmArray = body.JSONArray;
if (fmArray == nil || [fmArray count] == 0) {
NSNumber *accountId = (NSNumber *)[mDictionary objectForKey:#"accountId"];
} else {
NSMutableArray *mArray = [[NSMutableArray alloc] init];
[mArray addObject:mDictionary];
for (int i = 0; i < fmArray.count; i++) {
NSDictionary *fmDictionary = [fmArray objectAtIndex:i];
mDictionary = [[NSMutableDictionary alloc] init];
NSNumber *accountId = (NSNumber *)[fmDictionary objectForKey:#"id"];
[mDictionary setObject:accountId forKey:#"accountId"];
[mDictionary setObject:[fmDictionary objectForKey:#"name"] forKey:#"name"];
[mDictionary setObject:[fmDictionary objectForKey:#"relation"] forKey:#"relation"];
[mArray addObject:mDictionary];
}
[[NSThread currentThread] isMainThread] ? NSLog(#"6MAIN THREAD") : NSLog(#"6NOT MAIN THREAD");
[self gotoSelectFamilyMembers:mArray];
}
}
- (void) gotoSelectFamilyMembers:(NSMutableArray *) mArray {
dispatch_async(dispatch_get_main_queue(), ^{
GCHFamilyMembersViewConroller* fmViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"gchFamilyMembers"];
fmViewController._tblData = mArray;
self.navigationController.viewControllers = #[fmViewController];
[self.mm_drawerController setCenterViewController:self.navigationController withCloseAnimation:YES completion:nil];
});
}

Answer 1

Try below code:
dispatch_async(dispatch_get_main_queue(), ^{
GCHFamilyMembersViewConroller* fmViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"gchFamilyMembers"];
fmViewController._tblData = mArray;
((AppDelegate*)[[UIApplication sharedApplication]delegate]).navigationController.viewControllers = #[fmViewController];
[self.mm_drawerController setCenterViewController:((AppDelegate*)[[UIApplication sharedApplication]delegate]).navigationController withCloseAnimation:YES completion:nil];
});

Answer 2

You're using the asynchronous calls of Unirest and the response should be called on the UI thread (Main thread). Usually libraries similar to this deliver the result on the main thread. Therefore, I think you do not need to specifically call dispatch_async on the main queue. However, you can use the following check to see whether it gets called on the main thread or not.
[[NSThread currentThread] isMainThread] ? NSLog(#"MAIN THREAD") : NSLog(#"NOT MAIN THREAD");
Here's what I suspect
Your ViewController creation method has some fault and is consuming time
Your response is very large
I suggest that you call the following without any web service calls to confirm that they do not cause the crash.
GCHFamilyMembersViewConroller* fmViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"gchFamilyMembers"];
self.navigationController.viewControllers = #[fmViewController];
[self.mm_drawerController setCenterViewController:self.navigationController withCloseAnimation:YES completion:nil];