Question

Is there any way to disable the image preview after taking a picture with the UIImagePickerController? I want to dismiss the ImagePicker as soon as the user pressed the shutter release button.

Answer 1

I asked a similar question here

My solution was to create a customized view on top of the default UIImagePickerControllerView.

I downloaded the example Augmented Reality

Then you can use the OverlayView.m and OverlayView.h by adding them to your project:
I made the custom picker toolbar, picker and overlayView global so that I can access them anywhere in the project.

In your ViewController.h

@class OverlayView;

@interface ViewController //bla bla...
{
UIImagePickerController * picker;
UIToolbar *toolBar;
OverlayView *overlayView; 
}

I created the controls of the toolbar a camera button and the cancel button

// toolbar - handy if you want to be able to exit from the image picker...
            toolBar=[[[UIToolbar alloc] initWithFrame:CGRectMake(0, 480-55, 320, 55)] autorelease];
            toolBar.barStyle =  UIBarStyleBlackOpaque;
            NSArray *items=[NSArray arrayWithObjects:
                            [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCancel  target:self action:@selector(cancelPicture)] autorelease],
                            [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace  target:nil action:nil] autorelease],
                            [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCamera  target:self action:@selector(shootPicture)] autorelease],
                            [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace  target:nil action:nil] autorelease],
                            [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace  target:nil action:nil] autorelease],
                            nil];
            [toolBar setItems:items];

            // create the overlay view
            overlayView=[[[OverlayView alloc] initWithFrame:CGRectMake(0, 0, 320, 480-44)] autorelease];
            // important - it needs to be transparent so the camera preview shows through!
            overlayView.opaque=NO;
            overlayView.backgroundColor=[UIColor clearColor];

                    // parent view for our overlay
        UIView *parentView=[[[UIView alloc] initWithFrame:CGRectMake(0,0,320, 480)] autorelease];
        [parentView addSubview:overlayView];
        [parentView addSubview:toolBar];

        // configure the image picker with our overlay view
        picker=[[UIImagePickerController alloc] init];
        picker.sourceType = UIImagePickerControllerSourceTypeCamera;

        // hide the camera controls
        picker.showsCameraControls=NO;
        picker.wantsFullScreenLayout = YES;

The cancel method

- (IBAction)cancel {
    // Don't pass current value to the edited object, just pop.
    [self.navigationController popViewControllerAnimated:YES];
}

The (shootPictureMethod):

-(void) shootPicture {

    [picker takePicture];

}

To exit without showing preview just dismiss the view after taking the picture in the didFinishPickingImage method

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)img editingInfo:(NSDictionary *)editInfo 
{
//do whatever

[self dismissModalViewControllerAnimated:YES];
}