How to display count of notifications in app launcher icon
Android (“vanilla” android without custom launchers and touch interfaces) does not allow changing of the application icon, because it is sealed in the .apk
tightly once the program is compiled. There is no way to change it to a ‘drawable’ programmatically using standard APIs. You may achieve your goal by using a widget instead of an icon. Widgets are customisable. Please read this :
As for badge numbers. As I said before – there is no standard way for doing this. But we all know that Android is an open operating system and we can do everything we want with it, so the only way to add a badge number – is either to use some 3-rd party apps or custom launchers, or front-end touch interfaces: Samsung TouchWiz or Sony Xperia’s interface. Other answers use this capabilities and you can search for this on stackoverflow, e.g.
As you see this is not an actual Facebook app it’s TouchWiz. In vanilla android this can be achieved with Nova Launcher http://forums.androidcentral.com/android-applications/199709-how-guide-global-badge-notifications.html So if you will see icon badges somewhere, be sure it is either a 3-rd party launcher or touch interface (frontend wrapper). May be sometime Google will add this capability to the standard Android API.
It works in samsung/htc launcher
public static void setBadge(Context context, int count) {
String launcherClassName = getLauncherClassName(context);
if (launcherClassName == null) {
return;
}
Intent intent = new Intent("android.intent.action.BADGE_COUNT_UPDATE");
intent.putExtra("badge_count", count);
intent.putExtra("badge_count_package_name", context.getPackageName());
intent.putExtra("badge_count_class_name", launcherClassName);
context.sendBroadcast(intent);
}
public static String getLauncherClassName(Context context) {
PackageManager pm = context.getPackageManager();
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
List<ResolveInfo> resolveInfos = pm.queryIntentActivities(intent, 0);
for (ResolveInfo resolveInfo : resolveInfos) {
String pkgName = resolveInfo.activityInfo.applicationInfo.packageName;
if (pkgName.equalsIgnoreCase(context.getPackageName())) {
String className = resolveInfo.activityInfo.name;
return className;
}
}
return null;
}