What is android:contentDescription="@string/desc" in ImageView's xml?
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I added an imageView in Graphical Layout but it looks different on my real device and on AVD.I found that I need to add contentDescription in xml,but when I add contentDescription="@string/desc" there is an error:"No resource found that matches the given name (at 'contentDescription' with value '@string/desc').".What does this string "desc"?How it should looks like?