XML : Android change "up" button image

I am creating an Android application with custom navigation bar.

My current navigation bar looks like this:

I would like to create a navigation bar like this:

To create a navigation bar like this, at first I need to change default Android "up" button. To achieve this In developers forums I have found a way:

  <style name="Theme.MyTheme" parent="android:Theme.Holo">      <item name="android:homeAsUpIndicator">@drawable/my_up_indicator</item>  </style>    

I have placed this style in styles.xml file (v21 also):

  <style name="AppTheme.NoActionBar">      <item name="windowActionBar">false</item>      <item name="windowNoTitle">true</item>      <item name="android:windowDrawsSystemBarBackgrounds">true</item>      <item name="android:statusBarColor">@android:color/transparent</item>        <item name="android:homeAsUpIndicator">@drawable/custom_up_button</item>  </style>    

Sadly, this doesn't change my "up" button. I must be doing something wrong. Does anyone know what?