android-attributes

I can't find any information about the differences between: android:textColor="?attr/colorPrimary" vs android:textColor="?colorPrimary" I have read that "?attr" means attribute value specified in the current theme, but without "attr" it gives the same result (=color defined in my theme). It behaves similar with other attributes? For example: Does android:background="?attr/selectableItemBackground" equals android:background="?selectableItemBackground" ? Here it's told that it differs. Thanks very much. Ok, I have finally found in the docs: Because the system resource tool knows that an

I want to have 2 selectable themes for my application. In order to do that, I defined some attributes, like this: <attr format="color" name="item_background" /> Then, I created both themes, like this: <style name="ThemeA"> <item name="item_background">#123456</item> </style> <style name="ThemeB"> <item name="item_background">#ABCDEF</item> </style> This method works great, allowing me to create and modify several themes easily. The problem is that it seems that it can be used only in Views, and not in Drawables . For example, referencing a value from a View inside a layout works: <TextView