Trying to make a screenshot button that sends the screenshot to my camera roll, when the button is clicked. Swift 3, Xcode 8, IOS

Question

Swift 3, Xcode 8, IOS:

I can't seem to figure out what I'm doing wrong, no errors show up, but when I click the button in my app, nothing happens and nothing is saved in my simulators camera roll.

This is what I've done for the button in the view controller:

import UIKit
class ViewController: ViewController {

override func viewDidLoad() { 
    super.viewDidLoad() 
}

override func didReceiveMemoryWarning() { 
    super.didReceiveMemoryWarning() 
}

@IBAction func buttonAction(_ sender: UIButton) {
    func captureScreen() {

        UIGraphicsBeginImageContextWithOptions(view.bounds.size, false, UIScreen.main.scale)
        view.layer.render(in: UIGraphicsGetCurrentContext()!)
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        UIImageWriteToSavedPhotosAlbum(image!, nil, nil, nil)
    }
}
}

score 4 · Accepted Answer · answered Feb 15 '17 at 17:19

4

The problem is you have put screenshot taking code inside nested function of your buttonAction method name captureScreen and never called that method, there is no need to add nested method. So simply remove that function and put the screenshot code directly inside the button action method. So replace your button action with this one.

@IBAction func buttonAction(_ sender: UIButton) {

    UIGraphicsBeginImageContextWithOptions(view.bounds.size, false, UIScreen.main.scale)
    view.layer.render(in: UIGraphicsGetCurrentContext()!)
    let image = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()

    UIImageWriteToSavedPhotosAlbum(image!, nil, nil, nil)        
}

answered Feb 15 '17 at 17:19

Nirav D

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"This app has crashed because it attempted to access privacy-sensitive data without a usage description. The app's Info.plist must contain an NSPhotoLibraryUsageDescription key with a string value explaining to the user how the app uses this data. (lldb) " – MontgommeryJR Feb 15 '17 at 17:30
@DanielG Check this answer for that http://stackoverflow.com/a/40012626/6433023 and add privacy photo library in you info.plist – Nirav D Feb 15 '17 at 17:32
YES, THANK YOU! :) – MontgommeryJR Feb 15 '17 at 17:47
@DanielG Welcome mate :) – Nirav D Feb 15 '17 at 17:47
1

@NiravD +1 Thank you so much, it helped – Ritesh.mlk Apr 21 '17 at 11:17

Jayce · Answer 2 · 2017-06-10T20:04:53.090

In Swift 3.1

First you need to edit your info.plist file

import Photos

then add the uibutton:

@IBOutlet weak var shutterButton: UIButton!



@IBAction func shotAction(_ sender: Any) {
    guard shutterButton.isEnabled else {
        return
    }

    let takeScreenshotBlock = {
        //Render and capture an UIView named view:
        self.shutterButton.isHidden = true
        UIGraphicsBeginImageContextWithOptions(self.view.frame.size, false, 0.0)
        self.view.drawHierarchy(in: self.view.frame, afterScreenUpdates: true)
        if let image = UIGraphicsGetImageFromCurrentImageContext() {
            UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil)
        }
        UIGraphicsEndImageContext();
        self.shutterButton.isHidden = false


        DispatchQueue.main.async {
            // briefly flash the screen
            let flashOverlay = UIView(frame: self.sceneView.frame)
            flashOverlay.backgroundColor = UIColor.white
            self.sceneView.addSubview(flashOverlay)
            UIView.animate(withDuration: 0.25, animations: {
                flashOverlay.alpha = 0.0
            }, completion: { _ in
                flashOverlay.removeFromSuperview()
            })
        }
    }
    switch PHPhotoLibrary.authorizationStatus() {
    case .authorized:
        takeScreenshotBlock()
    case .restricted, .denied:
        let alertController = UIAlertController(title: "Photo access denied", message: "Please enable Photos Library access for this appliction in Settings > Privacy.", preferredStyle: UIAlertControllerStyle.alert)
        let actionOK = UIAlertAction(title: "OK", style: .cancel, handler: nil)
        alertController.addAction(actionOK)
        present(alertController, animated: true, completion: nil)
    case .notDetermined:
        PHPhotoLibrary.requestAuthorization({ (status) in
            if status == .authorized {
                takeScreenshotBlock()
            }
        })
    }
}

Trying to make a screenshot button that sends the screenshot to my camera roll, when the button is clicked. Swift 3, Xcode 8, IOS

2 Answers2