Android: how to customize default themes and styles

What is Style?

A style is a collection of properties that specify the look and format for a View or window. A style can specify properties such as height, padding, font color, font size, background color, and much more. A style is defined in an XML resource that is separate from the XML that specifies the layout.

Default Styles of android platform – here

What is Theme?

A theme is a style applied to an entire Activity or application, rather than an individual View (as in the example above). When a style is applied as a theme, every View in the Activity or application will apply each style property that it supports.

Default themes of android platform – here

To customize Themes and Styles of android platforms, you need to specify the attributes that are necessary to change. You may do the following things:

1. Find out default attributes of themes and styles which are needed to change as your requirements. If necessary see default attributes.
2. Derive custom themes and styles by inheriting from default platform’s  themes and styles.
3. Modify/change necessary attributes of these.
4. Specify this theme in activity declaration in AndroidMenifest.xml file.
5. Specify if necessary styles in view declaration in layout out file.
6. that’s all.

Details code examples are here:

Custom themes for Window title bar, Listview, and Dialog in …/res/values/themes.xml –

<?xml version=”1.0″ encoding=”utf-8″?>
<resources>
<style name=”customTheme1″ parent=”android:Theme”>
<item name=”android:windowTitleSize”>25dip</item>
<item name=”android:windowTitleBackgroundStyle”>@style/WindowTitleBackground1</item>
<item name=”android:listViewStyle”>@style/ipicsListView</item>
<item name=”android:listViewWhiteStyle”>@style/ipicsListView</item>
</style>
<style name=”customDialog” parent=”android:Theme.Dialog”>
@drawable/my_panel_background
</style>
</resources>

Custom Styles in …/res/values/styles.xml –

<?xml version=”1.0″ encoding=”utf-8″?>
<resources>
<style name=”WindowTitleBackground1″ parent=”android:WindowTitleBackground”>
@drawable/custom_header
</style>
<style name=”customListView” parent=”@android:style/Widget.ListView”>
@drawable/list_selector_background_focus
<item name=”android:background”>@android:color/white</item>
<item name=”android:cacheColorHint”>@color/white</item>
</style>
</resources>

AndroidaManifest.xml –

<activity android:name=”.LoginActivity” android:theme=”@style/customTheme”></activity>

<activity android:name=”.ProductsListActivity” android:theme=”@style/customTheme”></activity>

References:

http://developer.android.com/guide/topics/ui/themes.html#Properties