Screenshot on Swift Programmatically

Screenshot on swift programmatically

If you have some sort of Objective-C knowledge then here is the answer that you want.

Open this Link and follow the last answer which iterates through all the view hierarchy and And have line by line comments to fully understand the code.

The Image is finally converted into both NSData and UIImage.
If you are still confuse then i can convert it into swift but first try it by your self.

Here is the Swift code of that Answer.

func screenshot() -> UIImage {
    let imageSize = UIScreen.main.bounds.size as CGSize;
    UIGraphicsBeginImageContextWithOptions(imageSize, false, 0)
    let context = UIGraphicsGetCurrentContext()
    for obj : AnyObject in UIApplication.shared.windows {
        if let window = obj as? UIWindow {
            if window.responds(to: #selector(getter: UIWindow.screen)) || window.screen == UIScreen.main {
                                // so we must first apply the layer's geometry to the graphics context
                                context!.saveGState();
                                // Center the context around the window's anchor point
                                context!.translateBy(x: window.center.x, y: window.center
                                    .y);
                                // Apply the window's transform about the anchor point
                                context!.concatenate(window.transform);
                                // Offset by the portion of the bounds left of and above the anchor point
                context!.translateBy(x: -window.bounds.size.width * window.layer.anchorPoint.x,
                                     y: -window.bounds.size.height * window.layer.anchorPoint.y);

                                // Render the layer hierarchy to the current context
                                window.layer.render(in: context!)

                                // Restore the context
                                context!.restoreGState();
            }
        }
    }
    let image = UIGraphicsGetImageFromCurrentImageContext();
    return image!
}

Get screenshot of current screen in iOS/swift for sharing

// to create an image from screenshot

UIGraphicsBeginImageContext(view.frame.size)
view.layer.renderInContext(UIGraphicsGetCurrentContext())
let image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()

// to share the image

var imagesToShare = [AnyObject]()
imagesToShare.append(image)

let activityViewController = UIActivityViewController(activityItems: imagesToShare , applicationActivities: nil)
activityViewController.popoverPresentationController?.sourceView = self.view
presentViewController(activityViewController, animated: true, completion: nil)

How to take screenshot of a UIView in swift?

For drawing of one view, just use this:

    // Begin context
    UIGraphicsBeginImageContextWithOptions(view.bounds.size, false, UIScreen.mainScreen().scale)

    // Draw view in that context
    drawViewHierarchyInRect(view.bounds, afterScreenUpdates: true)

    // And finally, get image
    let image = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()

If you want to use it multiple times, probably extension would do the job:

//Swift4

extension UIView {

    func takeScreenshot() -> UIImage {

        // Begin context
        UIGraphicsBeginImageContextWithOptions(self.bounds.size, false, UIScreen.main.scale)

        // Draw view in that context
        drawHierarchy(in: self.bounds, afterScreenUpdates: true)

        // And finally, get image
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        if (image != nil)
        {
            return image!
        }
        return UIImage()
    }
}

//Old Swift

extension UIView {

    func takeScreenshot() -> UIImage {

        // Begin context
        UIGraphicsBeginImageContextWithOptions(self.bounds.size, false, UIScreen.mainScreen().scale)

        // Draw view in that context
        drawViewHierarchyInRect(self.bounds, afterScreenUpdates: true)

        // And finally, get image
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return image
    }
}

To explain what those parameters do:

UIGraphicsBeginImageContextWithOptions() creates a temporary rendering
context into which the original is drawn. The first argument, size, is
the target size of the scaled image. The second argument, isOpaque is
used to determine whether an alpha channel is rendered. Setting this
to false for images without transparency (i.e. an alpha channel) may
result in an image with a pink hue. The third argument scale is the
display scale factor. When set to 0.0, the scale factor of the main
screen is used, which for Retina displays is 2.0 or higher (3.0 on the
iPhone 6 Plus).

More about it here http://nshipster.com/image-resizing/

As for the draw call, Apple Docs explains it to detail here and here

Programmatically Screenshot | Swift 3, macOS

Yes its possible. This function takes all connected monitors screenshots and writes to specified path as jpg file. Generates file name as unix time stamp.

 func TakeScreensShots(folderName: String){
    
    var displayCount: UInt32 = 0;
    var result = CGGetActiveDisplayList(0, nil, &displayCount)
    if (result != CGError.success) {
        print("error: \(result)")
        return
    }
    let allocated = Int(displayCount)
    let activeDisplays = UnsafeMutablePointer<CGDirectDisplayID>.allocate(capacity: allocated)
    result = CGGetActiveDisplayList(displayCount, activeDisplays, &displayCount)
    
    if (result != CGError.success) {
        print("error: \(result)")
        return
    }
       
    for i in 1...displayCount {
        let unixTimestamp = CreateTimeStamp()
        let fileUrl = URL(fileURLWithPath: folderName + "\(unixTimestamp)" + "_" + "\(i)" + ".jpg", isDirectory: true)
        let screenShot:CGImage = CGDisplayCreateImage(activeDisplays[Int(i-1)])!
        let bitmapRep = NSBitmapImageRep(cgImage: screenShot)
        let jpegData = bitmapRep.representation(using: NSBitmapImageRep.FileType.jpeg, properties: [:])!
        
        
        do {
            try jpegData.write(to: fileUrl, options: .atomic)
        }
        catch {print("error: \(error)")}
    }
}

func CreateTimeStamp() -> Int32
{
    return Int32(Date().timeIntervalSince1970)
}

How to take a screenshot programmatically on iOS

I'm answering this question as it's a highly viewed, and there are many answers out there plus there's Swift and Obj-C.

Disclaimer This is not my code, nor my answers, this is only to help people that land here find a quick answer. There are links to the original answers to give credit where credit is due!! Please honor the original answers with a +1 if you use their answer!

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Using QuartzCore

#import <QuartzCore/QuartzCore.h> 

if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) {
    UIGraphicsBeginImageContextWithOptions(self.window.bounds.size, NO, [UIScreen mainScreen].scale);
} else {
    UIGraphicsBeginImageContext(self.window.bounds.size);
}

[self.window.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData *imageData = UIImagePNGRepresentation(image);
if (imageData) {
    [imageData writeToFile:@"screenshot.png" atomically:YES];
} else {
    NSLog(@"error while taking screenshot");
}

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In Swift

func captureScreen() -> UIImage
{

    UIGraphicsBeginImageContextWithOptions(self.view.bounds.size, false, 0);

    self.view.drawViewHierarchyInRect(view.bounds, afterScreenUpdates: true)

    let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()

    UIGraphicsEndImageContext()

    return image
}

Note: As the nature with programming, updates may need to be done so please edit or let me know! *Also if I failed to include an answer/method worth including feel free to let me know as well!

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