Android: secure AppStore Launch (aka protocol takover check)

gistfile1.txt

# any apps that registers market:// could be part of user selection list
# only google play ID is allowed
# need to check for such application existence then launch the intent.

public static void secureAppStoreLaunch(Context context) {
    // you can also use BuildConfig.APPLICATION_ID
    String appId = context.getPackageName();
    Intent rateIntent = new Intent(Intent.ACTION_VIEW,
        Uri.parse("market://details?id=" + appId));
    boolean marketFound = false;

    // find all applications able to handle our rateIntent
    final List otherApps = context.getPackageManager()
        .queryIntentActivities(rateIntent, 0);
    for (ResolveInfo otherApp: otherApps) {
        // look for Google Play application
        if (otherApp.activityInfo.applicationInfo.packageName
                .equals("com.android.vending")) {

            ActivityInfo otherAppActivity = otherApp.activityInfo;
            ComponentName componentName = new ComponentName(
                    otherAppActivity.applicationInfo.packageName,
                    otherAppActivity.name
                    );
            // make sure it does NOT open in the stack of your activity
            rateIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            // task reparenting if needed
            rateIntent.addFlags(Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);
            // if the Google Play was already open in a search result
            //  this make sure it still go to the app page you requested
            rateIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
            // this make sure only the Google Play app is allowed to
            // intercept the intent
            rateIntent.setComponent(componentName);
            context.startActivity(rateIntent);
            marketFound = true;
            break;

        }
    }

    // if GP not present on device, open web browser
    if (!marketFound) {
        Intent webIntent = new Intent(Intent.ACTION_VIEW,
            Uri.parse("https://play.google.com/store/apps/details?id="+appId));
        context.startActivity(webIntent);
    }
}