<style name="MyActivityTheme" parent="android:Theme.Light" >
      <item name="android:windowTitleBackgroundStyle">@style/windowTitleBackgroundStyle</item>
      <item name="android:windowTitleStyle">@style/windowTitleStyle</item>
      <!-- Window Header Height -->
      <item name="android:windowTitleSize">54dp</item>
  </style>
 
  <!-- Preference Settings Window Title -->
  <style name="windowTitleBackgroundStyle">
      <item name="android:background">#CCE8CF</item>
      </style>
     
      <style name="windowTitleStyle">
      <item name="android:textColor">#FF0000</item>
      <item name="android:paddingLeft">25dp</item>
      <item name="android:textSize">20sp</item>
      </style>

<activity
    android:name="com.example.stylewindowtitle.MainActivity"
    android:label="@string/app_name"
    android:theme="@style/MyActivityTheme"
>
<!--code goes here-->