Basic example for sharing text or image with UIActivityViewController in Swift

Question

I started my search by wanting to know how I could share to other apps in iOS. I discovered that two important ways are

• UIActivityViewController
• UIDocumentInteractionController

These and other methods are compared in this SO answer.

Often when I am learning a new concept I like to see a basic example to get me started. Once I get something basic set up I can modify it how I like later.

There are many SO questions related to UIActivityViewController, but I couldn't find any that were just asking for a simple example. Since I just learned how to do this, I will provide my own answer below. Feel free to add a better one (or an Objective-C version).

Answer 1

UIActivityViewController Example Project

Set up your storyboard with two buttons and hook them up to your view controller (see code below).

Add an image to your Assets.xcassets. I called mine "lion".

Code

import UIKit
class ViewController: UIViewController {

    // share text
    @IBAction func shareTextButton(_ sender: UIButton) {

        // text to share
        let text = "This is some text that I want to share."

        // set up activity view controller
        let textToShare = [ text ]
        let activityViewController = UIActivityViewController(activityItems: textToShare, applicationActivities: nil)
        activityViewController.popoverPresentationController?.sourceView = self.view // so that iPads won't crash

        // exclude some activity types from the list (optional)
        activityViewController.excludedActivityTypes = [ UIActivityType.airDrop, UIActivityType.postToFacebook ]

        // present the view controller
        self.present(activityViewController, animated: true, completion: nil)

    }

    // share image
    @IBAction func shareImageButton(_ sender: UIButton) {

        // image to share
        let image = UIImage(named: "Image")

        // set up activity view controller
        let imageToShare = [ image! ]
        let activityViewController = UIActivityViewController(activityItems: imageToShare, applicationActivities: nil)
        activityViewController.popoverPresentationController?.sourceView = self.view // so that iPads won't crash

        // exclude some activity types from the list (optional)
        activityViewController.excludedActivityTypes = [ UIActivityType.airDrop, UIActivityType.postToFacebook ]

        // present the view controller
        self.present(activityViewController, animated: true, completion: nil)
    }

}

Result

Clicking "Share some text" gives result on the left and clicking "Share an image" gives the result on the right.

Notes

• I retested this with iOS 11 and Swift 4. I had to run it a couple times in the simulator before it worked because it was timing out. This may be because my computer is slow.
• If you wish to hide some of these choices, you can do that with excludedActivityTypes as shown in the code above.
• Not including the popoverPresentationController?.sourceView line will cause your app to crash when run on an iPad.
• This does not allow you to share text or images to other apps. You probably want UIDocumentInteractionController for that.

See also

• Add sharing to your Swift app via UIActivityViewController
• UIActivity​View​Controller from NSHipster
• UIActivityViewController documentation
• Share extension documentation
• comparison with UIDocumentInteractionController