launch containing app from iOS8 Custom Keyboard

Question

I want to launch my containing app.

I tried using URL schemes.

The URL scheme launched the app from other places - so the problem is not there.

Looks like this object is nil:

   self.extensionContext

thus i can't run this method:

[self.extensionContext openURL:url completionHandler:nil];

Can I launch my app? Do URL Schemes work in a custom keyboard?

thanks!

Check This Answer [Open My application from my keyboard extension in swift 3.0](https://stackoverflow.com/a/44718613/2150318) — Kamal Upasena, Jul 05 '17 at 06:55
https://forums.raywenderlich.com/t/open-my-application-from-my-keyboard-extension-in-swift-3-0/21121/2?u=leangchhean — Sour LeangChhean, Mar 27 '18 at 15:05

score 15 · Answer 1 · answered Apr 10 '15 at 06:22

15

Try this code

    UIResponder* responder = self;
    while ((responder = [responder nextResponder]) != nil)
    {
        NSLog(@"responder = %@", responder);
        if([responder respondsToSelector:@selector(openURL:)] == YES)
        {
            [responder performSelector:@selector(openURL:) withObject:[NSURL URLWithString:urlString]];
        }
    }

answered Apr 10 '15 at 06:22

DongHyun Jang

401
5
4

Thanks for your answer, but for me, opening URL Scheme doesn't work, opening Universal Links works fine. – Changwei Feb 07 '18 at 04:27

Valentin Shergin · Answer 2 · 2016-04-28T20:48:05.240

Here is working solution (tested on iOS 9.2) for Keyboard Extension. This category adds special method for access to hidden sharedApplication object and then call openURL: on it. (Of course then you have to use openURL: method with your app scheme.)

// Usage:
// UIInputViewController.openURL(NSURL(string: "your-app-scheme://")!)
extension UIInputViewController {

    func openURL(url: NSURL) -> Bool {
        do {
            let application = try self.sharedApplication()
            return application.performSelector("openURL:", withObject: url) != nil
        }
        catch {
            return false
        }
    }

    func sharedApplication() throws -> UIApplication {
        var responder: UIResponder? = self
        while responder != nil {
            if let application = responder as? UIApplication {
                return application
            }

            responder = responder?.nextResponder()
        }

        throw NSError(domain: "UIInputViewController+sharedApplication.swift", code: 1, userInfo: nil)
    }

}

Lately I developed slightly different approach:

// Usage:
// UIApplication.sharedApplication().openURL(NSURL(string: "your-app-scheme://")!)

extension UIApplication {

    public static func sharedApplication() -> UIApplication {
        guard UIApplication.respondsToSelector("sharedApplication") else {
            fatalError("UIApplication.sharedKeyboardApplication(): `UIApplication` does not respond to selector `sharedApplication`.")
        }

        guard let unmanagedSharedApplication = UIApplication.performSelector("sharedApplication") else {
            fatalError("UIApplication.sharedKeyboardApplication(): `UIApplication.sharedApplication()` returned `nil`.")
        }

        guard let sharedApplication = unmanagedSharedApplication.takeUnretainedValue() as? UIApplication else {
            fatalError("UIApplication.sharedKeyboardApplication(): `UIApplication.sharedApplication()` returned not `UIApplication` instance.")
        }

        return sharedApplication
    }

    public func openURL(url: NSURL) -> Bool {
        return self.performSelector("openURL:", withObject: url) != nil
    }

}

That's strange, it works for me. Which approach have you tested? — Valentin Shergin, May 02 '16 at 19:34
Oh, i've tested your secondary way and it works. Why do you have a rocket emoji on your method? — TomSawyer, May 03 '16 at 02:36
Uh, that's great! I am using symbol here because I can, because I love emojis and because we cannot use names `openURL` or `sharedApplication` here because they exist but marked as `unavailable`. — Valentin Shergin, May 03 '16 at 19:34
Well, i asked because if i delete the rocket emoji. I've got this error : `Method 'sharedApplication()' with Objective-C selector 'sharedApplication' conflicts with previous declaration with the same Objective-C selector` — TomSawyer, May 03 '16 at 20:50
P.s: If we write this in latest swift syntax, it won't compile — KrishnaCA, Jun 08 '16 at 10:12
@ValentinShergin would this work in the iMessage extensions? I'm trying to figure out a way to perform an authentication that requires openURL http://stackoverflow.com/questions/38459871/how-to-handle-oauth-style-log-ins-with-imessage-apps-in-ios-10-xcode-8 — GarySabo, Jul 21 '16 at 16:26

score 10 · Accepted Answer · answered Jul 06 '14 at 13:18

10

To answer MY OWN question:

In an iOS8 custom keyboard, the extensionContext object is nil, thus I can't use it to launch the containing app.

The workaround I came up with is:

create a url scheme for your app
add a UIWebView to your inputView
load the url scheme for your containing app in the webview

I'm not sure if Apple will allow this to happen, but it works now.

answered Jul 06 '14 at 13:18

nurnachman

4,468
2
37
40

Does apple still allow this now? I can’t seem to get a UIWebView working inside the UIInputViewController. Let me know if it still works for you! – ThE_-_BliZZarD Sep 11 '14 at 18:24
@ThE_-_BliZZarD make sure you enabled AllowFullAccess in the keyboard settings – nurnachman Sep 11 '14 at 18:34
@ThE_-_BliZZarD let us know if it helped! – nurnachman Sep 13 '14 at 03:20
@ThE_-_BliZZarD have you got the solution of above question ? – Jaha Rabari Nov 29 '14 at 18:16
Ah sorry, I added this comment for a friend - and he then created his own account to add the answer below. Therefore please look at the answer by Andi. – ThE_-_BliZZarD Nov 30 '14 at 03:15
2

@BastienBeurier it looks like it doesn't work on the 8.3 beta1 – nurnachman Feb 27 '15 at 20:38
App would be rejected if you open external app. As per apple review guideline section 4.4.1 see this: > They must not: > Include marketing, advertising, or in-app purchases; > Launch other apps besides Settings; or – codelover Jun 20 '17 at 01:40

score 5 · Answer 4 · edited Nov 19 '15 at 06:46

5

Apple does not allow any app extensions other than Today extensions to open the containing app.

From the guidelines:

A Today widget (and no other app extension type) can ask the system to open its containing app by calling the openURL:completionHandler: method of the NSExtensionContext class.

You can check Here

edited Nov 19 '15 at 06:46

iHulk

4,869
2
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answered Feb 04 '15 at 06:20

user3246173

488
6
18

score 2 · Answer 5 · answered Dec 08 '14 at 13:22

According to Apple's documentation https://developer.apple.com/library/ios/documentation/General/Conceptual/ExtensibilityPG/index.html, you should use NSExtensionContext like this:

NSExtensionContext *ctx = [[NSExtensionContext alloc] init];
[ctx openURL:[NSURL URLWithString:@"myapp://"] completionHandler:^(BOOL success){return ;}];

score 2 · Answer 6 · answered Jun 22 '16 at 19:35

A Swift 2.2 version, akin to DongHyun Jang's answer for Objective-C:

func webLink(urlString: String) {
    let url = NSURL(string: urlString)
    var responder: UIResponder? = self
    while let r = responder {
        if r.respondsToSelector("openURL:") {
            r.performSelector("openURL:", withObject: url)
            break;
        }
        responder = r.nextResponder()
    }  
}

score 2 · Answer 7 · answered Jan 25 '17 at 03:46

I tried to do above solutions for latest xcode 8.2 and swift 3.0.

Unfortunately. I can't get it work. So I found my own solution and it works well in swift 3.0, xcode 8.2

   func openURL(_ url: URL) {
        return
   }

   func openApp(_ urlstring:String) {

       var responder: UIResponder? = self as UIResponder
       let selector = #selector(openURL(_:))
       while responder != nil {
           if responder!.responds(to: selector) && responder != self {
              responder!.perform(selector, with: URL(string: urlstring)!)
              return
             }
             responder = responder?.next
          }
   }

  // Usage
  //call the method like below
  //self.openApp(urlString)

  //URL string need to included custom scheme.
  //for example, if you created scheme name = customApp
  //urlString will be "customApp://?[name]=[value]"
  //self.openApp("customApp://?category=1")

This does not compile, throws error: `Use of unresolved identifier 'openURL'`. This works but is deprecated: `let selector: Selector = "openURL:"` — Jordan H, Feb 26 '17 at 18:37

Julio Bailon · Answer 8 · 2015-06-01T02:00:53.150

This is what I found to open any URL using what has been described above:

UIWebView * webView = [[UIWebView alloc] initWithFrame:CGRectMake(0, 0, 0, 0)];
NSString *urlString = @"https://itunes.apple.com/us/app/watuu/id304697459";
NSString * content = [NSString stringWithFormat : @"<head><meta http-equiv='refresh' content='0; URL=%@'></head>", urlString];
[webView loadHTMLString:content baseURL:nil];
[self.view addSubview:webView];
[webView performSelector:@selector(removeFromSuperview) withObject:nil afterDelay:2.0];

Please note that in this case I am instantiating this call from the UIInputViewController.

This method should also work using the URL scheme from the containing app

NOTE: As of iOS 8.3 Apple has killed this method

score 1 · Answer 9 · answered Jan 25 '15 at 20:41

In an App Extension (ex: custom keyboard), that would have been handled through UIViewController.extensionContext but as of iOS 8.1.2, the field is nil in the following Swift call:

self.extensionContext?.openURL(appURL, completionHandler: nil)
// Does nothing because extensionContext is nil (iOS 8.1)

Actually, it is not possible either to use Application.sharedApplication.openURL(...) in an App Extension as stated in Apple documentation.

So, as of 8.1.2, the workaround is to use a dumb UIWebView to redirect to the containing app like this:

let webView = UIWebView(frame: CGRectMake(0, 0, 0, 0));
let url = "MyKeyboard://";
let content = "<head><meta http-equiv='refresh' content='0; URL=\(url)'></head>";
webView.loadHTMLString(content, baseURL: nil);
self.view.addSubview(webView);
let delayInSeconds = 2.0
let startTime = dispatch_time(DISPATCH_TIME_NOW, Int64(delayInSeconds * Double(NSEC_PER_SEC)))
dispatch_after(startTime, dispatch_get_main_queue()) { () -> Void in
    webView.removeFromSuperview()
}

Where MyKeyboard:// must be defined accordingly as URL scheme in the containing app.

Please take note that I don't know yet whether this is approved by Apple. Forwarding to apps from custom keyboards may be bad enough for user experience.

score 1 · Answer 10 · edited Jun 20 '20 at 09:12

1

As per Apple review guidelines for Extension, it is now not advised to open external apps from the extension.

For reference please see apple review guidelines

Section 4.4.1

They must not:

Include marketing, advertising, or in-app purchases;

Launch other apps besides Settings; or

edited Jun 20 '20 at 09:12

Community

1
1

answered Jun 20 '17 at 01:45

codelover

1,113
10
28

Andi · Answer 11 · 2014-09-12T22:12:23.247

0

I struggled with this for a couple of days. I could not get the UIWebView working inside the custom keyboard.

Fix: put it inside the viewDidAppear:animated instead of viewDidLoad (on another note this is where the code for the keyboard's custom height should stay as well).

Code:

- (void)viewDidAppear:(BOOL)animated {
    UIWebView * webView = [[UIWebView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
    NSString * content = @"<a href='your_app_schema://your_params'>anchor</a>";
    [webView loadHTMLString:content baseURL:nil];
    [self.view addSubview:webView];
}

edited Sep 12 '14 at 22:12

answered Sep 12 '14 at 22:07

Andi

1
1

I think it's annoying that everything ends up in viewDidAppear rather than viewDidLoad... What do you think? – nurnachman Sep 13 '14 at 03:20

score 0 · Answer 12 · answered Aug 24 '22 at 02:33

let selectorOpenURL = NSSelectorFromString("openURL:")
var responder: UIResponder? = self
while let r = responder {
    if r.canPerformAction(selectorOpenURL, withSender: nil) {
         r.perform(selectorOpenURL, with: url, afterDelay: 0.01)
         break
    }
    responder = r.next
}

launch containing app from iOS8 Custom Keyboard

12 Answers12

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