hinterbu hinterbu - 1 year ago 57
iOS Question

How to show live camera preview as soon as iOS app launches?

I am following a tutorial on building a camera app here: https://www.appcoda.com/ios-programming-camera-iphone-app/

It is a simple app with an image view and two buttons, one to take a photo, the other to select a photo from the devices photo library.

So at the moment when I press on the Take Photo button, the camera appears and I can take a picture and so on.

But is there a way to show the live camera preview as soon as the app launches and opens without having to first press Take Photo explicitly? How would I trigger that in viewDidLoad, or elsewhere? Do I need to use AV Foundation?

At the moment my program is using the image picker controller to present the camera to the user using this code:

- (IBAction)takePhoto:(UIButton *)sender {

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

[self presentViewController:picker animated:YES completion:NULL];


Answer Source

Sorry for the short answer but yes, you need to use AVFoundation. There is no decent way to embed the UIImagePickerController to your view.

You could, of course, use -[UIViewController addChildViewController:] and then add the imagePickers view as subview into your viewController:

[[self view] addSubview:[pickerVC view]];

[self addChildViewController:pickerVC];
[pickerVC didMoveToParentViewController:self];

But to be honest, you might better implement the camera using AVFoundation, as the approach above might seem kinda "hackish" nowadays, as I personally think. Also you'd need to properly deal with auto layout and I don't really know, if the UIImagePickerViewController in particular likes to be treated like this. Keep in mind that these components are built for specific use cases and to serve a special purpose, not as usual subclassable, open solution like UIViewController