You can use reference identifiers to indirectly reference colors.
The color IDs are available under the your-package.R.color namespace.
Android defines a base set of colors, which are accessible through the
Android android.R.color namespace.
The following shows some examples of specifying color in an XML resource file.
<resources>
<color name="red">#f00</color>
<color name="blue">#0000ff</color>
<color name="green">#f0f0</color>
<color name="main_back_ground_color">#ffffff00</color>
</resources>
The entries above need to be in a file residing in the /res/values subdirectory.
The name of the file can be anything you choose.
The following code shows an example of using a color resource in Java code.
int mainBackGroundColor = activity.getResources.getColor(R.color.main_back_ground_color);
main_back_ground_color is defined in the resource file above.
As string resource, we can reference color resource in layout.
The following code shows how you can use a color resource in a view definition.
<resources>
<color name="red">#f00</color>
<color name="blue">#0000ff</color>
<color name="green">#f0f0</color>
<color name="main_back_ground_color">#ffffff00</color>
</resources>
The following code shows how to use defined color in layout resource.
<TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:textColor="@color/red" android:text="Sample Text to Show Red Color"/>