Widget.AppCompat.Button.Colored Button transparent when disabled

Question

I'm trying to fight the default behaviour of the Widget.AppCompat.Button.Colored style. By default the button is semi transparent. I want it to be opaque. Here is my code:

Button in layout:

<Button
    android:id="@+id/search"
    style="@style/Widget.AppCompat.Button.Colored"
    android:theme="@style/AccentButton"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Search"/>

styles.xml

<style name="AccentButton" parent="ThemeOverlay.AppCompat.Light">
    <item name="colorAccent">@color/colorAccent</item>
    <item name="colorButtonNormal">#f00</item>
</style>

If I remove the style="@style/Widget.AppCompat.Button.Colored" part the button will not turn transparent if disabled.

I've tried to look into the Appcompat/Android source code. No luck though. I can't find the part where it is set to be transparent. The goal is the get a nice solution using mostly AppCompat code. I know I can create a custom drawable button backgroud. I would like to avoid it. Any ideas?

Answer 1

The solution is to use: <item name="android:disabledAlpha">1.0</item> like this:

<style name="AccentButton" parent="ThemeOverlay.AppCompat.Light">
    <item name="colorAccent">@color/colorAccent</item>
    <item name="colorButtonNormal">#f00</item>
    <item name="android:disabledAlpha">1.0</item>
</style>

How I got to this answer

After some struggle I've found btn_colored_material.xml source code.

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_enabled="false"
          android:alpha="?attr/disabledAlpha"
          android:color="?attr/colorButtonNormal" />
    <item android:color="?attr/colorAccent" />
</selector>

It uses the disabledAlpha attribute. So it was only a matter of using it.

One thing I still don't get is why I have to use it with the android: prefix. I would expect that:

• ?android:attr/something to be set with <item name='android:something'>(...)
• ?attr:something to be set with <item name='something'>(...)

My guess is that if Android soruce code code uses it's own attributes it doesn't need the prefix.