How to take a photo using the camera and UIImagePickerController

Swift version: 5.10

Paul Hudson @twostraws May 28th 2019

UIKit has a built-in view controller designed to let the user take photos, crop them as needed, them load them directly into your app. Even better, it only takes a few lines of code to use!

First, make your view controller conform to both UINavigationControllerDelegate, and UIImagePickerControllerDelegate.

Second, add this code wherever you want to trigger the camera process:

let vc = UIImagePickerController()
vc.sourceType = .camera
vc.allowsEditing = true
vc.delegate = self
present(vc, animated: true)

The sourceType property is what directs the view controller to the camera rather than the user’s saved image library.

Third, add the didFinishPickingMediaWithInfo method, which gets called by the image picker when an image was selected. You need to read it out of the info dictionary using the key .editedImage, but then you have a UIImage that you can do whatever you want with.

This example code should get you started:

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
    picker.dismiss(animated: true)

    guard let image = info[.editedImage] as? UIImage else {
        print("No image found")
        return
    }

    // print out the image size as a test
    print(image.size)
}

That’s all the code needed to make the camera work, but there is one last change you need: reading images from the camera requires a new Info.plist key describing how you plan to use the data.

To add this, open your Info.plist file, right-click on some space below the rows, then choose Add Row. Give it the name “Privacy - Camera Usage Description”, then enter a description in the value area – this will be shown to users the first time you try to use the camera.