ActionBarCompat & Transparency

Question

I would like to make the ActionBar in the support library fully transparent, however, it seems that changing the background drawable won't suffice since the backgrounds stack. If you put a semi-transparent background you end up with the default background behind it.

Does anyone know a way to remove that background?

This is what happens:

The code for the background drawable:

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="#66336688"/>
</shape>

As you can see, the drawable has a transparent blue that overlaps with the default gray background.

Answer 1

Ok, I found the solution messing around with the SDK. It seems that it is pretty simple, you need to do 3 things:

• Create a background drawable as shown on my question.

• Create an ActionBar style like so:

  <!-- Application theme. -->
  <style name="AppTheme" parent="Theme.AppCompat.Light">
      <item name="android:actionBarStyle">@style/MyActionBar</item>
  
      <!-- Support library compatibility -->
      <item name="actionBarStyle">@style/MyActionBar</item>
  </style>
  
  <!-- ACTION BAR STYLES -->
  <style name="MyActionBar" parent="@style/Widget.AppCompat.ActionBar">
      <item name="android:background">@drawable/actionbar_background</item>
      <item name="android:windowActionBarOverlay">true</item>
  
      <!-- Support library compatibility -->
      <item name="background">@drawable/actionbar_background</item>
      <item name="windowActionBarOverlay">true</item>
  </style>
  

• Use the Window feature for ActionBar overlay using the Support method (ignore Eclipse's warning regarding API level for the constant; I used the SuppressLint annotation to remove the warning):

  @SuppressLint("InlinedApi") @Override protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  supportRequestWindowFeature(Window.FEATURE_ACTION_BAR_OVERLAY);
  setContentView(R.layout.activity_home);}
  

Answer 2

ChristianGuerrero answer is great but you should directly put the item:

<item name="android:windowActionBarOverlay">true</item>

inside the AppTheme style. Then you don't have to add anything in your onCreate method.