Parse iOS Universal Links with Nativescript Angular?

Question

Following the apple documentation and Branch's documentation here, I have set up a working universal link in my Nativescript Angular (iOS) app. But, how do I parse the link when the app opens?

For example, when someone opens the app from the link, I want to have my app read the link so it can go to the correct page of the app.

There is some helpful code in this answer, but I keep getting errors with it. This could be bc the code is written in vanilla JS and I am not translating it into Angular correctly. The use of "_extends" and "routeUrL" both cause errors for me.

And the Nativescript url-handler plugin does not seem to work without further code.

So, after setting up the universal link, and installing the nativescript url-handler plugin, I have entered the following in app.module.ts:

const Application = require("tns-core-modules/application");

import { handleOpenURL, AppURL } from 'nativescript-urlhandler';
declare var NSUserActivityTypeBrowsingWeb

if (Application.ios) {   
  const MyDelegate = (function (_super) {

   _extends(MyDelegate, _super);
    function MyDelegate() {
      _super.apply(this, arguments);
    }
    MyDelegate.prototype.applicationContinueUserActivityRestorationHandler = function (application, userActivity) {
      if (userActivity.activityType === NSUserActivityTypeBrowsingWeb) {
        this.routeUrl(userActivity.webpageURL);
      }
      return true;
    };
    MyDelegate.ObjCProtocols = [UIApplicationDelegate];
    return MyDelegate;
  })(UIResponder);
  Application.ios.delegate = MyDelegate;
}

...
export class AppModule {

ngOnInit(){
        handleOpenURL((appURL: AppURL) => {
            console.log('Got the following appURL = ' + appURL);
        });
    } 
}

The trouble seems to be mostly with "_extends" and "_super.apply". For example, I get this error:

'NativeScript encountered a fatal error: TypeError: undefined is not an object (evaluating '_extends')

EDIT: Note that the nativescript-urlhandler plugin is no longer being updated. Does anyone know how to parse universal links with Nativescript?

Answer 1

I have figured out a method to get this working:

The general idea is to use the iOS App Delegate method: applicationContinueUserActivityRestorationHandler.

The syntax in the Nativescript documentation on app delegates did not work for me. You can view that documentation here.

This appears to work:

--once you have a universal link set up, following documentation like here, and now you want your app to read ("handle") the details of the link that was tapped to open the app:

EDIT: This code sample puts everything in one spot in app.module.ts. However, most of the time its better to move things out of app.module and into separate services. There is sample code for doing that in the discussion here. So the below has working code, but keep in mind it is better to put this code in a separate service.

app.module.ts

    declare var UIResponder, UIApplicationDelegate
    if (app.ios) {
        app.ios.delegate = UIResponder.extend({
            applicationContinueUserActivityRestorationHandler: function(application, userActivity) {
                if (userActivity.activityType === NSUserActivityTypeBrowsingWeb) {
                    let tappedUniversalLink = userActivity.webpageURL
                    console.log('the universal link url was = ' + tappedUniversalLink)
                } 
                return true;
            }
        },
        {
           name: "CustomAppDelegate",
            protocols: [UIApplicationDelegate]
        });
   }

NOTE: to get the NSUserActivity/Application Delegate stuff to work with typescript, I also needed to download the tns-platforms-declarations plugin, and configure the app. So:

$ npm i tns-platforms-declarations

and

references.d.ts

/// <reference path="./node_modules/tns-platform-declarations/ios.d.ts" />

The above code works for me to be able to read the details of the tapped universal link when the link opens the app.

From there, you can determine what you want to do with that information. For example, if you want to navigate to a specific page of your app depending on the details of the universal link, then I have found this to work:

app.module.ts

    import { ios, resumeEvent, on as applicationOn, run as applicationRun, ApplicationEventData } from "tns-core-modules/application";

    import { Router } from "@angular/router";

    let univeralLinkUrl = ''

    let hasLinkBeenTapped = false

    if (app.ios) {
       //code from above, to get value of the universal link
        applicationContinueUserActivityRestorationHandler: function(application, userActivity) {
                if (userActivity.activityType === NSUserActivityTypeBrowsingWeb) {
                   hasLinkBeenTapped = true  
                   universalLinkUrl =  userActivity.webpageURL
                } 
                return true;
        },

            {
                name: "CustomAppDelegate",
                protocols: [UIApplicationDelegate]
            });

    }

    @ngModule({...})

    export class AppModule {
       constructor(private router: Router) {

            applicationOn(resumeEvent, (args) => {
               if (hasLinkBeenTapped === true){
                   hasLinkBeenTapped = false  //set back to false bc if you don't app will save setting of true, and always assume from here out that the universal link has been tapped whenever the app opens
                   let pageToOpen = //parse universalLinkUrl to get the details of the page you want to go to
                   this.router.navigate(["pageToOpen"])
                } else {
                    universalLinkUrl = '' //set back to blank
                    console.log('app is resuming, but universal Link has not been tapped') 
                }
            })
        }
    }

Answer 2

You can use the nativescript-plugin-universal-links plugin to do just that. It has support for dealing with an existing app delegate so if you do have another plugin that implements an app delegate, both of them will work.

Here's the usage example from the docs:

import { Component, OnInit } from "@angular/core";
import { registerUniversalLinkCallback } from "nativescript-plugin-universal-links";

@Component({
  selector: "my-app",
  template: "<page-router-outlet></page-router-outlet>"
})
export class AppComponent {
  constructor() {}

  ngOnInit() {
    registerUniversalLinkCallback(ul => {
      // use the router to navigate to the screen
    });
  }
}

And the callback will receive a ul (universal link) param that looks like this

{
  "href": "https://www.example.com/blog?title=welcome",
  "origin": "https://www.example.com",
  "pathname": "/blog",
  "query": {
     "title": "welcome"
  }
}

Disclaimer: I'm the author of the plugin.