iPhone Camera App-如何保持在相机视图中？

Question

I've implemented the camera inside of my app with the default showsCameraControls = YES, and the issue I am having is when the user confirms that the image is a keeper, it dismisses the camera with [self.delegate didFinishWithCamera]. I would like to remain in the Camera view until the user is done taking photos. Without [self.delegate didFinishWithCamera], the app hangs after the user confirms they want to keep the photo and never returns back to the live camera feed. How do I remain in the camera view? Your help is appreciated!

@implementation PHFPhotoOverlayVC

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        self.imagePickerController = [[UIImagePickerController alloc] init];
        self.imagePickerController.delegate = self;
    }
    return self;
}

- (void)setupImagePicker:(UIImagePickerControllerSourceType)sourceType
{
    self.imagePickerController.sourceType = sourceType;

    if (sourceType == UIImagePickerControllerSourceTypeCamera)
    {
        self.imagePickerController.mediaTypes =
            [NSArray arrayWithObjects:(NSString *) kUTTypeImage, nil];
        self.imagePickerController.showsCameraControls = YES;

#if false
        if ([[self.imagePickerController.cameraOverlayView subviews] count] == 0)
        {
            CGRect overlayViewFrame = self.imagePickerController.cameraOverlayView.frame;
            CGRect newFrame = CGRectMake(0.0,
                                         CGRectGetHeight(overlayViewFrame) -
                                         self.view.frame.size.height - 10.0,
                                         CGRectGetWidth(overlayViewFrame),
                                         self.view.frame.size.height + 10.0);
            self.view.frame = newFrame;
            [self.imagePickerController.cameraOverlayView addSubview:self.view];
        }
#endif
    }
}


#pragma mark -
#pragma mark UIImagePickerControllerDelegate

- (void)    imagePickerController:(UIImagePickerController *)picker
    didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    self.imagePickerController.mediaTypes =
        [NSArray arrayWithObjects:(NSString *) kUTTypeImage, nil];
    self.imagePickerController.showsCameraControls = YES;


    UIImage *image = [info valueForKey:UIImagePickerControllerOriginalImage];
    if (self.delegate)
        [self.delegate didTakePicture:image];

    [self.delegate didFinishWithCamera];
}

- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
{
    [self.delegate didFinishWithCamera];
}

@end

Answer 1

In order to achieve this, you will have to implement your own method for taking a picture, since this default button causes the view to dismiss itself.

Obviously, you can do this by setting showsCameraControls=NO, but then you'd have to recreate all the other functionality that you still want.

I've never done this, but it should be possible to leave showsCameraControls=YES and use the cameraOverlayView to simply layer an identical "Take Picture" button over the existing one. If you do that, you just need to have that button call the method -takePicture from the instance of your UIImagePickerViewController.

Hopefully that's enough, feel free to comment and ask for any clarification.

Answer 2

You're going to need to implement a custom camera - check out Apple's SquareCam example

You'll be using AVFoundation and will be able to implement any kind of custom behavior when a photo is taken (including just staying on that camera page) - you'll even have to save it to the Photo Library yourself (the SquareCam example shows you how to do this). This also means that if you need the crop/resize controls, you'll have to create them yourself, as well as a picker view (grid gallery view) if you want the user to be able to review their photos after taking them.

It's probably around intermediate level stuff - took me a few days to implement, but if your app is in any way focused on photos, this is definitely the way to go. Gives you complete control of the camera UI and behavior.

Oh, and yeah you'll have to implement the flash button, shutter button, shutter effect, tap to focus, and anything else yourself too. AVFoundation basically gives you a straight pipe to the camera lens (figuratively).