App:showasaction Vs Android:showasaction

I am building an Android app and want to have a button always visible on the actionBar. I followed this guide and others, but none of them seem to solve my problem (although they a

Solution 1:

This is the documentation of the lint rule:

AppCompatResource

Summary: Menu namespace

Priority: 5 / 10

Severity: Error

Category: Usability

When using the appcompat library, menu resources should refer to the showAsAction in the app: namespace, not the android: namespace.

Similarly, when not using the appcompat library, you should be using the android:showAsAction attribute.

I think the problem is that you are mixing Framework Activity and AppCompat menu.

You should use AppCompatActivity with AppCompat Action bar and app:showAsAction; or Activity with android:showAsAction.