将UIImage传递给第二个视图控制器会滞后过渡

Question

I'm using a UIImagePickerController to select an image from my photo album. Once I've selected the image, I'm passing the image through to a second view controller and displaying it in a UIImageView. See code below:

First view controller:

- (IBAction)selectPhoto
{
    imagePicker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
    [self presentModalViewController:self.imagePicker animated:YES];
}

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{    
    UploadViewController *uploadViewController = [[UploadViewController alloc] initWithNibName:@"UploadViewController" bundle:nil];
    [uploadViewController setImage:[info objectForKey:@"UIImagePickerControllerOriginalImage"]];

    [picker pushViewController:uploadViewController animated:YES];
}

Second view controller:

- (void)viewDidLoad
{
    [super viewDidLoad];

    // Set the image view image
    imageView.image = self.image;
}

The code does the job, however, when I push from the image picker to my second view controller, it lags as it's transitioning.

Ideally I would like a smooth transition but I would be happy if it just waited half a second or something and then moves smoothly.

Can any explain why this could be happening and how/if I can get around it?

Thanks.

Answer 1

延迟可能来自渲染图像，您可以尝试让UploadViewController的初始视图包含活动微调器，然后实际上在viewDidAppear方法中设置图像，该方法应在动画完成后调用。

Answer 2

Try with this , here timer is introduced in order to provide delay(0.5sec) ,

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{    
    [NSTimerscheduledTimerWithTimeInterval:0.5 target:self selector:@selector(timerAction:) userInfo:info repeats:NO];
}


-(void)timerAction:(NSTimer *)timer
{
  UploadViewController *uploadViewController = [[UploadViewController alloc] initWithNibName:@"UploadViewController" bundle:nil];
    [uploadViewController setImage:[[timer userInfo]objectForKey:@"UIImagePickerControllerOriginalImage"]];

    [picker pushViewController:uploadViewController animated:YES];
   [uploadViewController release];
}