Ionic2应用通过URL Scheme调用另一款Ionic2应用时卡顿问题求助

Hey there, let's tackle that frustrating issue where your Ionic 2 App A can only occasionally successfully launch App B via the otherapp:// URL scheme—most of the time getting stuck on the loading screen. Your current workaround (having App B launch App A first then callback) works, but it's definitely not ideal for user experience. Here are some better, more robust solutions:

1. Make the URL Scheme Invocation More Reliable #

• Check if App B is running first: Before trying to launch App B from App A, verify if it's already in the background using a plugin like cordova-plugin-appavailability. This way you can choose between bringing it to the foreground (faster) or cold-starting it:

  import { AppAvailability } from '@ionic-native/app-availability/ngx';
  import { Platform } from '@ionic/angular';
  
  constructor(private appAvailability: AppAvailability, private platform: Platform) {}
  
  checkAndLaunchAppB() {
    let appIdentifier: string;
    if (this.platform.is('ios')) {
      appIdentifier = 'otherapp://';
    } else if (this.platform.is('android')) {
      appIdentifier = 'com.yourcompany.otherapp'; // Replace with App B's Android package name
    }
  
    this.appAvailability.check(appIdentifier)
      .then(
        () => {
          // App B is running, bring it to foreground
          window.open('otherapp://', '_system');
        },
        () => {
          // App B is not running, handle cold start (maybe show a temporary loading indicator)
          window.open('otherapp://', '_system');
        }
      );
  }
  

• Wait for App A to fully load before invoking: Don't trigger the launch in ionViewWillEnter—use ionViewDidEnter instead, ensuring App A's UI and resources are fully ready before sending the launch request.
• Use a dedicated launcher plugin: Instead of relying on window.open, try @ionic-native/app-launcher which provides better error handling and callbacks for success/failure of the launch attempt:

  import { AppLauncher } from '@ionic-native/app-launcher/ngx';
  
  constructor(private appLauncher: AppLauncher) {}
  
  launchAppB() {
    this.appLauncher.canLaunch('otherapp://')
      .then((canLaunch) => {
        if (canLaunch) {
          this.appLauncher.launch('otherapp://')
            .then(() => console.log('App B launched successfully'))
            .catch(err => console.error('Error launching App B', err));
        } else {
          // Handle case where App B isn't installed (e.g., redirect to app store)
        }
      })
      .catch(err => console.error('Error checking App B availability', err));
  }
  

2. Optimize App B's Startup Performance #

The stall is likely happening because App B takes too long to cold-start. Speed it up with these tweaks:

• Delay non-critical initialization: Move heavy setup tasks (like bulk API calls, large module imports) from app.component.ts constructor to ionViewDidEnter or use async/await to run them in the background without blocking the UI.
• Streamline URL routing on launch: When App B is opened via the URL scheme, immediately route to the target page instead of letting the default routing flow run. Use handleOpenURL to capture the incoming URL and navigate directly:

  // In App B's app.component.ts
  handleOpenURL(url: string) {
    // Skip unnecessary splash screen delays
    setTimeout(() => {
      this.navCtrl.navigateRoot('/target-page'); // Directly jump to the required page
    }, 100);
  }
  

• Optimize splash screen settings: Configure the splash screen to hide as soon as the first page is ready, instead of waiting for a fixed duration. Update your config.xml:

  <preference name="SplashScreenDelay" value="0" />
  <preference name="AutoHideSplashScreen" value="true" />
  

3. Switch to More Reliable Deep Linking Methods #

URL schemes can be flaky on modern OS versions. For better consistency, use platform-specific deep linking:

• iOS Universal Links: Associate your domain with App B so links to your domain open the app directly (no more scheme prompts). Use cordova-plugin-deeplinks to set this up.
• Android App Links: Similar to Universal Links, it lets your app be the default handler for your domain, ensuring reliable launches without system dialogs.

These methods are more robust because they're integrated with the OS's app linking system, reducing the chance of stalls during launch.

4. Debug to Pinpoint the Exact Stall Point #

To make sure you're fixing the right issue, add detailed logging:

• In App A, log timestamps before and after the launch attempt.
• In App B, log every step of the startup process (constructor, platform ready, route navigation) to see where the delay is happening.
• Use Xcode Instruments (iOS) or Android Studio Profiler (Android) to check for main thread blocking operations that could be causing the loading stall.

Your current workaround works, but implementing these solutions will give users a smoother, more consistent experience without the extra back-and-forth between apps.

内容的提问来源于stack exchange，提问作者sompop kulapalanont