Change android colorPrimary (app bar) to gradient color

Question

I need to change color on my application bar to some gradient color. I created action_bar_bg.xml file in drawable folder:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <gradient
        android:angle="90"
        android:centerColor="@color/colorPrimaryDark"
        android:endColor="@color/colorPrimary"
        android:startColor="@color/colorPrimary" />
</shape>

and I tried to change colorPrimary in styles.xml:

<!-- Base application theme. -->
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <!-- Customize your theme here. -->

    <item name="colorPrimary">@drawable/action_bar_bg</item>

</style>

but it doesn't work. I am getting error: android.content.res.Resources$NotFoundException: File res/drawable/action_bar_bg.xml from color state list resource ID #0x7f020046) I want to achieve that result:

What do I have to change in code?

Answer 1

try on this way. There's a new attribute called colorPrimary which you can define in your Theme. This will give you ActionBar or Toolbar a solid color.

Following a little example:

<style name="AppTheme" parent="Theme.AppCompat.Light">
    <!-- colorPrimary is used for the default action bar background -->
    <item name="colorPrimary">@color/my_action_bar_color</item>
</style>

Please note: It has to be only colorPrimary, not android:colorPrimary, in every values-folder except the values-v21 one.

You can read more about customizing the Color Palette on Android

Answer 2

Do this in your onCreate in your Activity

ActionBar bar = getActionBar();
Drawable gradient = getResources().getDrawable( R.drawable.action_bar_bg);
bar.setBackgroundDrawable(gradient);