What class does Android use to communicate a request for an action to be performed?

Which AsyncTask method does not run on the UI thread?

How to notify a Fragment is visible when they are inside a ViewPager?

Which method should be used to refresh the ActionBar if you use ActionBarCompat library?

Which theme's attribute changes the color of the status bar in Lollipop?

Default behavior of an Activity when you manually rotate the device screen?

Which common design patterns are used in Android?

What's the output? final Intent mainIntent = new Intent(Intent.ACTION_MAIN, null); mainIntent.addCategory(Intent.CATEGORY_LAUNCHER); final List pkgAppsList = getPackageManager().queryIntentActivities(mainIntent, 0); for (Object object : pkgAppsList) { ResolveInfo info = (ResolveInfo) object; File file = new File(info.activityInfo.applicationInfo.publicSourceDir); // … }

If you are going to check a network connection with the below source code, what would be required to make it work? public boolean isOnline() { ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo netInfo = cm.getActiveNetworkInfo(); if (netInfo != null && netInfo.isConnectedOrConnecting()) return true; return false; }

what is the purpose of generating R.java as follows?

What's the output? public int pxToDp(int px) { DisplayMetrics displayMetrics = getContext().getResources().getDisplayMetrics(); int dp = Math.round(px / (displayMetrics.xdpi / DisplayMetrics.DENSITY_DEFAULT)); return dp; } public int dpToPx(int dp) { DisplayMetrics displayMetrics = getContext().getResources().getDisplayMetrics(); int px = Math.round(dp * (displayMetrics.xdpi / DisplayMetrics.DENSITY_DEFAULT)); return px; }