Launching an Android App from an Adobe AIR App

A while back I figured out how to setup an Adobe AIR app as an Android Device's launcher. Surprisingly, the tricky part of that project was figuring out how I can allow my customer to remove the app as launcher when they are done testing. I'm able to use adb to install and uninstall the app at will, but as tools go, that is way too complicated for my client to figure out.

While rocking out last night it hit me: if I could convince my AIR app to launch the Android Package Manager app, then my client could trivially uninstall our launcher app. After all, installing a new launcher doesn't take away any functionality, it just removes access to it. One hitch: to my knowledge the AIR SDK doesn't offer an API call I could invoke to kick off the package manager. But, as the music was blaring, I had my second epiphany: I bet I could use some magic URL convention to kick off the specific app I had in mind.

I spent the morning Googling around looking for Android specific URI prefixes. After all, if tel: would kick off the dialer, maybe there's some similar convention for apps themselves?

My first clue came with this comment:

Alternatively, there is the "intent:" scheme. This allows you to describe nearly any Intent as a URI, which the browser will try to launch when clicked. To build such a scheme, the best way is to just write the code to construct the Intent you want launched, and then print the result of intent.toUri(Intent.URI_INTENT_SCHEME).

Aha! There is a magic URI structure, it seems, and it starts with intent:. As I continued to Google around, I had no luck finding the syntax for this seemingly useful URI structure.

And then I found my second clue. Buried in this answer was the following snippet:

 <a href="intent:#Intent;action=android.intent.action.VIEW;category=android.intent.c‌​ategory.DEFAULT;category=android.intent.category.BROWSABLE;package=com.test.proje‌​ct;end">Click link to launch</a>

It wasn't much to go on, but at least gave me hope and clue what a intent: URI looked like.

After much experimentation I finally arrived at:

var url:String = ("intent:#Intent;" +
                  "action=android.intent.action.MAIN;" +
                  "category=android.intent.category.LAUNCHER;" +
                  "component=com.android.settings/.Settings;" +
                  "end");
navigateToURL(new URLRequest(url));

To my shock, it worked flawlessly!

I found the values to set for action, category and component by watching the log output of adb.exe logcat while pressing the "Settings" icon on my tablet.

The above syntax should be extensible to invoke pretty much any intent you want. I'm really surprised I wasn't able to find any documentation on this, as it seems hugely powerful.

By the way, Plan B was to examine this native extension, and expand on it to add in invocation or uninstall capabilities. Though, it looks like that won't be necessary.