Is there a way to set drawable's Alpha using XML?

Question

Easy like itself . I wanna make an alpha button , which would have a selected drawable this way:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <!-- Play/Pause -->
    <item android:state_selected="false" android:drawable="@drawable/item" />
    <item android:state_selected="true" android:drawable="@drawable/item" />

</selector>

I would wanna make something like this:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <!-- Play/Pause -->
    <item android:alpha="125" android:state_selected="false" android:drawable="@drawable/item" />
    <item android:alpha="255" android:state_selected="true" android:drawable="@drawable/item" />

</selector>

Thanks for all .

Answer 1

It's been a while since the OP, but personally found a solution that worked a lot better for me than the suggested answers. Creating a BitmapDrawable makes is easily possible to set the alpha:

<?xml version="1.0" encoding="utf-8"?>
<bitmap xmlns:android="http://schemas.android.com/apk/res/android"
    android:src="@drawable/your_drawble"
    android:alpha="77">
</bitmap>

Alpha can be any value between 0 and 255. Note that it is sort of the inverse of the HEX color value alpha, as for example 70% alpha would be B3 in HEX and 77 in the BitmapDrawable.