Pushing other Android activity to foreground

Question

From a package A, I triggered running service from privileged package B. Package B performs an update of package A. Target device is using Android 9 (API Level 28). The update is successful (app version code has changed). But my issue is that after the update, package A is in background ; on my device, it is on the background app list, I have to manually press on it to bring it to the foreground.

I would like it to come back to the foreground after install.

What I tried:

• Sending a BroadcastIntent from package B to package A after install ; it looks like the intent is not received on package's A BroadcastReceiver (maybe due to the fact that it is in background or the app has been updated?)

• After install this command works if I run it manually through adb: "$ adb shell am start -n "com.mma.mainapp/com.mma.mainapp.MainActivity" -a android.intent.action.MAIN -c android.intent.category.LAUNCHER". So I tried performing it from package B after install after a delay: "am start -n "$mainAppPackage/$mainAppPackage.MainActivity" -a ${Intent.ACTION_MAIN} -c ${Intent.CATEGORY_LAUNCHER}".runCommand(File(".")).

• I also tried performing this from package B after install after a delay with correct permission but package A is not listed:

  private fun moveToFront(mainAppPackage: String) {
      val activityManager = getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager
      val recentTasks = activityManager.getRunningTasks(Int.MAX_VALUE)//activityManager.appTasks.map { it.taskInfo }
      for (i in recentTasks.indices) {
          log("PUSH Application executed : "
                  + recentTasks[i].baseActivity.toShortString()
                  + "\t\t ID: " + recentTasks[i].id + "")
          if (recentTasks[i].baseActivity.toShortString().indexOf(mainAppPackage) > -1) {
              log("PUSH TO FRONT : "
                      + recentTasks[i].baseActivity.toShortString()
                      + "\t\t ID: " + recentTasks[i].id + "")
              activityManager.moveTaskToFront(recentTasks[i].id, ActivityManager.MOVE_TASK_WITH_HOME)
          }
      }
  }
  

• Overriding package A's Application::onCreate(), to bring activity to front: val i = Intent(context, MainActivity::class.java); i.setAction(Intent.ACTION_MAIN); i.addCategory(Intent.CATEGORY_LAUNCHER); context.startActivity(i) // working in isolation but onCreate is not trigerred after apk update.

Is there some way to perform this task? (this should be doable, given package B is privileged (installed under /system/priv-app on rooted device using the standard procedure) and has the same signature as package A)

Answer 1

You need to start an Activity after the installation is complete. It is possible you start activity before installation is complete. To get app A update completion register a broadcast receiver like this:

private static final IntentFilter appUpdateIntentFilter = new IntentFilter();
static {
    appUpdateIntentFilter.addDataScheme("package");
    appUpdateIntentFilter.addAction(Intent.ACTION_PACKAGE_ADDED); 
}

private AppUpdateReceiver appUpdateReceiver = new AppUpdateReceiver();

then if you are starting the download from app B's service, register in onCreate and stop in onDestroy of the service:

private void registerBroadcastReceiver() {
    try {
        registerReceiver(appUpdateReceiver, appUpdateIntentFilter);
    } catch (IllegalArgumentException e) {
        // already registered
    }
}

private void unregisterBroadcastReceiver() {
    try {
        unregisterReceiver(appUpdateReceiver);
    } catch (IllegalArgumentException e) {
        // already unregistered
    }
}

class AppUpdateReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        //if packageName is for app A then start an activity of app A
        int uid = intent.getIntegerExtra(Intent.EXTRA_UID);
        String appName = context.getPackageManager().getNameForUid(uid);
        if(appName.equals("com.appA.PackageName")) {
            //start an activity of app A 
        }
    }
}