How to create an app locker in Android Studio

Get list of all installed app by following code.

1. final PackageManager pm = getPackageManager(); 
2. //get a list of installed apps. 
3. List packages = pm.getInstalledApplications(PackageManager.GET_META_DATA); 
4.  
5. for (ApplicationInfo packageInfo : packages) { 
6. Log.d(TAG, "Installed package :" + packageInfo.packageName); 
7. Log.d(TAG, "Source dir : " + packageInfo.sourceDir); 
8. Log.d(TAG, "Launch Activity :" + pm.getLaunchIntentForPackage(packageInfo.packageName));  
9. } 

Check for which app is opened currently

1. ActivityManager am = (ActivityManager) this.getSystemService(ACTIVITY_SERVICE); 
2. List l = am.getRecentTasks(1, ActivityManager.RECENT_WITH_EXCLUDED); 
3. Iterator i = l.iterator(); 
4. PackageManager pm = this.getPackageManager(); 
5. while (i.hasNext()) { 
6. ActivityManager.RunningAppProcessInfo info = (ActivityManager.RunningAppProcessInfo)(i.next()); 
7. try { 
8. CharSequence c = pm.getApplicationLabel(pm.getApplicationInfo( 
9. info.processName, PackageManager.GET_META_DATA)); 
10. Log.w("LABEL", c.toString()); 
11. } catch (Exception e) { 
12. // Name Not FOund Exception 
13. } 
14. } 

Now check if the current app is present in the BlockedAppsList, if it is there, you can show any screen with a block message.

You need to create service which will run in background.