通过渐进式Web应用程序打开Android应用程序

Question

I need to open the WhatsApp Android app from within a Progressive Web App (PWA). This works but only if a phone number is available:

HTML

<a href="intent://send/0123456789#Intent;scheme=smsto;package=com.whatsapp;action=android.intent.action.SENDTO;end">?">OPEN WHATSAPP ANDROID</a>  

Is there an intent to just open the app? (like if you would tap the app icon on the home screen)

Answer 1

If you find the package name and component of the main activity for WhatsApp, you can do like,

ComponentName cn = new ComponentName(whatsAppPkg, whatsAppActivity);
startActivity(new Intent().setComponent(cn));

If you have the WhatsApp APK, you can use a tool like apktool to decompile it and look for the info you need in the manifest. Might take a little experimentation to find the right activity. Also note this could break at any time when the WhatsApp app is updated and could be different for different versions of the app.

It's also possible that WhatsApp has a public action-name based intent filter. You'd have to refer to their documentation to figure that out.