How to remove the border behind the button?

Question

There is a grey border behind my app button, how can I remove this?

I defined the ImageButton like this:

<ImageButton     android:id="@+id/btn_photo_lib"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:onClick="startPhotoLibAction"     android:src="@drawable/library_blau_2" /> 

Answer 1

You have to use style="?android:attr/borderlessButtonStyle":

<ImageButton     android:id="@+id/btn_photo_lib"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:onClick="startPhotoLibAction"     android:src="@drawable/library_blau_2"     style="?android:attr/borderlessButtonStyle"/> 

Answer 2

try this :

<ImageButton         android:id="@+id/btn_photo_lib"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:onClick="startPhotoLibAction"         android:background="@android:color/transparent"         android:src="@drawable/library_blau_2" />