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UIImagePickerController not presenting in iOS 8

Is anyone else having an issue with UIImagePickerController in iOS 8? The method below works perfectly well in iOS 7 on an iPad, but I get the following error when I run this in XCode 6 (Beta 3 or 4) when I try to present the picker (last line). If it matters, the selection of the sourceType is coming from an alertView that is presented in the same place.

Warning: Attempt to present <UIImagePickerController: 0x7c0ae400>  on <CAGUCreateContactViewController: 0x7bf61a00> which is already presenting (null)

Method to open imagePicker.

- (void)openPhotoPicker:(UIImagePickerControllerSourceType)sourceType
{
    if ([UIImagePickerController isSourceTypeAvailable:sourceType]) {
        NSArray *availableMediaTypes = [UIImagePickerController availableMediaTypesForSourceType:sourceType];
        if ([availableMediaTypes containsObject:(NSString *)kUTTypeImage]) {
            UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
            imagePickerController.modalPresentationStyle = UIModalPresentationFullScreen;
            imagePickerController.sourceType = sourceType;
            imagePickerController.mediaTypes = @[(NSString *)kUTTypeImage];
            imagePickerController.delegate = self;

            self.imagePickerController = imagePickerController;

            if (sourceType == UIImagePickerControllerSourceTypeCamera) {
                [self presentViewController:self.imagePickerController animated:YES completion:nil];
            } else {                    
                if (self.popoverVC) {
                    [self.popoverVC dismissPopoverAnimated:YES];
                    self.popoverVC = nil;
                }

                self.popoverVC = [[UIPopoverController alloc] initWithContentViewController:imagePickerController];
                [self.popoverVC presentPopoverFromRect:self.nameAndPicCell.picture.frame inView:self.view permittedArrowDirections:UIPopoverArrowDirectionUp animated:YES];
            }
        }
    }
}

I think this is because in iOS 8, alert views and action sheets are actually presented view controllers ( UIAlertController ). So, if you're presenting a new view controller in response to an action from the UIAlertView , it's being presented while the UIAlertController is being dismissed. I worked around this by delaying the presentation of the UIImagePickerController until the next iteration of the runloop, by doing this:

[[NSOperationQueue mainQueue] addOperationWithBlock:^{
    [self openPhotoPicker:sourceType];
}];

However, the proper way to fix this is to use the new UIAlertController API on iOS 8 (ie use if ([UIAlertController class]) ... to test for it). This is just a workaround if you can't use the new API yet.

I agree with Ben Lings issue detection. I would suggest a simpler solution in case when using UIActionSheet. I simply moved my code that reacts on Action Sheet selection from:

- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex;
{
// my code
}

into:

- (void)actionSheet:(UIActionSheet *)actionSheet didDismissWithButtonIndex:(NSInteger)buttonIndex;  // after animation
{
// my code
}

This way app is guarantied that code will be executed AFTER UIActionSheet animation finishes.

Since UIAlertView has similar delegate method:

- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex;  // after animation
{
// my code
}

I suppose that similar solution may apply.

Here is a solution that worked for me

if([[[UIDevice currentDevice] systemVersion] floatValue]>=8.0)
{
    [[NSOperationQueue mainQueue] addOperationWithBlock:^{

        [self presentViewController:cameraUI animated:NO completion:nil];
    }];

}
else{

    [controller presentViewController:cameraUI animated:NO completion:nil];
}

Remember to alloc cameraUI

UIImagePickerController *cameraUI = [[UIImagePickerController alloc] init];
cameraUI.sourceType = UIImagePickerControllerSourceTypeCamera;

Build and Go!

I was facing the same problem in iOS 8. Then I saw the change log of the latest update to iOS ie 8.0.2 on the device.

It is mentioned in this update that_

"Fixes an issue that prevented some apps from accessing photos from Photo Library"

So test your app using XCode 6 on device with iOS 8.0.2 version it will work fine Don't test it on iOS 8.0 simulator.

This helped me, hope the same for you.

iOS 8.0.2更新日志的屏幕截图

UIImagePickerController *imagePickerController= [[UIImagePickerController alloc] init];
[imagePickerController setSourceType:UIImagePickerControllerSourceTypePhotoLibrary];

// image picker needs a delegate so we can respond to its messages
[imagePickerController setDelegate:self];
self.shouldCallViewWillAppear = NO;

if(IS_IOS8)
{
    [[NSOperationQueue mainQueue] addOperationWithBlock:^{
        // Place image picker on the screen
        [self presentViewController:imagePickerController animated:YES completion:nil];
    }];
}
else
{
    [self presentViewController:imagePickerController animated:YES completion:nil];
}

You can dismiss the presented view controller (if any) by using

[self.presentedViewController dismissViewControllerAnimated:YES completion:nil];

This worked for me.

All you need to do is dismiss already presented ViewController:

if (self.presentedViewController) {
    [self.presentedViewController dismissViewControllerAnimated:YES completion:nil];
}

[self openPhotoPicker:sourceType];

If it still produces error, put openPhotoPicker: to completion handler

On iOS 8 you should use the new API:

if (SYSTEM_VERSION_IOS_8) {
    self.imagePickerController.modalPresentationStyle = UIModalPresentationPopover;
    UIPopoverPresentationController *popPC = self.imagePickerController.popoverPresentationController;
    popPC.barButtonItem = self.popoverItem;
    popPC.permittedArrowDirections = UIPopoverArrowDirectionAny;
    [self presentViewController:self.imagePickerController animated:YES completion:nil]
}

I recommend you watch the 2014 WWDC session 228 a look in side presentation controllers

I simply did this:

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND,
                                         (unsigned long)NULL), ^(void) {

    [self retractActivePopover];

    dispatch_async(dispatch_get_main_queue(), ^ {

        _activePopover=imagePickerPopover;

        UIBarButtonItem *callingButton = (UIBarButtonItem*) sender;

        [imagePickerPopover presentPopoverFromBarButtonItem:callingButton permittedArrowDirections:UIPopoverArrowDirectionUp animated:YES];

    });

});

I went through a lot of pain coming up with a solution which works on both iPad and iPhone, this is the final code which some of it comes from comments of other people: the code has some bugs but it's a very good place to start :)

definitions :

__weak IBOutlet UIButton *attachButton;
UIImage *image;

button's action :

    - (IBAction)doAttach:(id)sender {
    UIActionSheet *action = [[UIActionSheet alloc] initWithTitle:@"Select image from" delegate:self cancelButtonTitle:@"Cancel" destructiveButtonTitle:nil otherButtonTitles:@"From library",@"From camera", nil] ;
    [action showInView:self.view];
  }



#pragma mark - ActionSheet delegates

- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex
{
    if( buttonIndex == 1 ) {
        AVAuthorizationStatus authStatus = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];
        if(authStatus == AVAuthorizationStatusAuthorized)
        {
            NSLog(@"%@", @"You have camera access");
        }
        else if(authStatus == AVAuthorizationStatusDenied)
        {
            NSLog(@"%@", @"Denied camera access");

            [AVCaptureDevice requestAccessForMediaType:AVMediaTypeVideo completionHandler:^(BOOL granted) {
                if(granted){
                    NSLog(@"Granted access to %@", AVMediaTypeVideo);
                } else {
                    [self.presentedViewController dismissViewControllerAnimated:YES completion:nil];
                    UIAlertController* alert = [UIAlertController alertControllerWithTitle:@“no camera access“
                                                                                   message: @“if you need to use camera in this application go to settings -> appName -> and turn on camera.”
                                                                            preferredStyle:UIAlertControllerStyleAlert];

                    UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@“ok” style:UIAlertActionStyleDefault
                                                                          handler:^(UIAlertAction * action) {
                                                                          }];
                    [alert addAction:defaultAction];

                    [self presentViewController:alert animated:YES completion:nil];


                    NSLog(@"Not granted access to %@", AVMediaTypeVideo);
                    return ;
                }
            }];
        }
        else if(authStatus == AVAuthorizationStatusRestricted)
        {
            [self.presentedViewController dismissViewControllerAnimated:YES completion:nil];
            UIAlertController* alert = [UIAlertController alertControllerWithTitle:@“no camera access“
                                                                                   message: @“if you need to use camera in this application go to settings -> appName -> and turn on camera.”
                                                                            preferredStyle:UIAlertControllerStyleAlert];

            UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@“ok” style:UIAlertActionStyleDefault
                                                                  handler:^(UIAlertAction * action) {
                                                                  }];
            [alert addAction:defaultAction];

            [self presentViewController:alert animated:YES completion:nil];


            NSLog(@"%@", @"Restricted, normally won't happen");
        }
        else if(authStatus == AVAuthorizationStatusNotDetermined)
        {
            NSLog(@"%@", @"Camera access not determined. Ask for permission.");

            [AVCaptureDevice requestAccessForMediaType:AVMediaTypeVideo completionHandler:^(BOOL granted) {
                if(granted){
                    NSLog(@"Granted access to %@", AVMediaTypeVideo);
                } else {
                    NSLog(@"Not granted access to %@", AVMediaTypeVideo);
                    return ;
                }
            }];
        }
        else
        {
            [self.presentedViewController dismissViewControllerAnimated:YES completion:nil];
            UIAlertController* alert = [UIAlertController alertControllerWithTitle:@“No camera access“
                                                                           message: @“error accusing camera”
                                                                    preferredStyle:UIAlertControllerStyleAlert];

            UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@“ok” style:UIAlertActionStyleDefault
                                                                  handler:^(UIAlertAction * action) {
                                                                  }];
            [alert addAction:defaultAction];

            [self presentViewController:alert animated:YES completion:nil];


            return;
            //NSLog(@"%@", @"Camera access unknown error.");
        }

        if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {


            UIImagePickerController *pickerView =[[UIImagePickerController alloc]init];
            pickerView.allowsEditing = YES;
            pickerView.delegate = self;
            pickerView.sourceType = UIImagePickerControllerSourceTypeCamera;


            if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad) {

                [ self.presentedViewController dismissViewControllerAnimated:YES completion:nil ];

                pickerView.modalPresentationStyle = UIModalPresentationPopover;
                UIPopoverPresentationController *popPC = pickerView.popoverPresentationController;
                popPC.sourceView = attachButton;
                popPC.permittedArrowDirections = UIPopoverArrowDirectionAny;
                [self presentViewController:pickerView animated:YES completion:nil];
            } else {
                [self presentModalViewController:pickerView animated:YES ];
            }
        }

    }else if( buttonIndex == 0 ) {

        ALAuthorizationStatus status = [ALAssetsLibrary authorizationStatus];
        switch (status) {
            case ALAuthorizationStatusRestricted:
            case ALAuthorizationStatusDenied:
            {
                [self.presentedViewController dismissViewControllerAnimated:YES completion:nil];
                UIAlertController* alert = [UIAlertController alertControllerWithTitle:@“no access to library”
                                                                               message: @“if you wish to access photos in this app go to settings -> appName-> and turn on photos .”
                                                                        preferredStyle:UIAlertControllerStyleAlert];

                UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@“ok” style:UIAlertActionStyleDefault
                                                                      handler:^(UIAlertAction * action) {
                                                                      }];
                [alert addAction:defaultAction];

                [self presentViewController:alert animated:YES completion:nil];

            }
                break;

            default:
            {
                UIImagePickerController *pickerView = [[UIImagePickerController alloc] init];
                pickerView.allowsEditing = YES;
                pickerView.delegate = self;

                [pickerView setSourceType:UIImagePickerControllerSourceTypePhotoLibrary];


                if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad) {

                    [ self.presentedViewController dismissViewControllerAnimated:YES completion:nil ];

                    pickerView.modalPresentationStyle = UIModalPresentationPopover;
                    UIPopoverPresentationController *popup = pickerView.popoverPresentationController;
                    popup.sourceView = attachButton;
                    popup.permittedArrowDirections = UIPopoverArrowDirectionAny;
                    [self presentViewController:pickerView animated:YES completion:nil];
                } else {
                    [self presentModalViewController:pickerView animated:YES ];
                }
            }
                break;
        }



    }
}

#pragma mark - PickerDelegates

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{

    [self dismissModalViewControllerAnimated:true];

    UIImage * img = [info valueForKey:UIImagePickerControllerEditedImage];
    image = img;

}

performSelector:withObject:afterDelay solved my problem.

also didDismissWithButtonIndex do the trick.

Max

Here's a Xamarin solution. What worked for me was to add my actions to a Dismissed event handler.

this.btnPhoto.TouchUpInside += (sender, e) =>
{
    actionSheet = new UIActionSheet ("Add Photo");
    actionSheet.AddButton ("Take Photo");
    actionSheet.AddButton ("Select from Library");
    actionSheet.AddButton ("Cancel");
    actionSheet.DestructiveButtonIndex = -1; // red
    actionSheet.CancelButtonIndex = 3;  // black
    actionSheet.Clicked += delegate(object a, UIButtonEventArgs b)
    {
        actionSheet.Dismissed += (object aSender, UIButtonEventArgs dismissArgs) => 
        {
            switch (dismissArgs.ButtonIndex)
            {
                case 0:
                    showCamera ();
                    break;
                case 1:
                    showPhotoLibrary ();
                    break;
            }
        };
    };
    actionSheet.ShowInView (view);
};

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