Actually, the loading images from URL to ImageView (ImageView itself is in GridView or ListView) is not a simple task. You should provide memory and disk caching to avoid reload image again and again.
The simpliest way to show progress in ActionBar is
super.onCreate(savedInstanceState); requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS); setContentView(R.layout.activity_main);
Karsch-Völk M, Barrett B, Kiefer D, Bauer R, Ardjomand-Woelkart K, Linde K
Preparations of the plant Echinacea are widely used in some European countries and in North America for common colds. Echinacea preparations available on the market differ greatly as different types (species) and parts (herb, root or both) of the plant are used, different manufacturing methods (drying, alcoholic extraction or pressing out the juice from fresh plants) are used and sometimes also other herbs are added.