Custom attributes in styles.xml
I figured it out! The answer is to NOT specify the namespace in the style.
<?xml version="1.0" encoding="utf-8" ?><resources xmlns:android="http://schemas.android.com/apk/res/android"> <style name="CustomStyle"> <item name="android:layout_width">wrap_content</item> <item name="android:layout_height">wrap_content</item> <item name="custom_attr">value</item> <!-- tee hee --> </style></resources>
above answer is worked for me, I tried a litte change, I declare styleable for a class in resources element.
<declare-styleable name="VerticalView"> <attr name="textSize" format="dimension" /> <attr name="textColor" format="color" /> <attr name="textBold" format="boolean" /></declare-styleable>in declare-styleable, the name attribute referenced a class name, so I had a view class call "com.my.package.name.VerticalView", it represented this declare must be use in VerticalView or subclasses of VerticalView. so we can declare style like this :
<resources> <style name="verticalViewStyle"> <item name="android:layout_width">match_parent</item> <item name="android:layout_height">36dip</item> <item name="textSize">28sp</item> <!-- not namespace prefix --> <item name="textColor">#ff666666</item> <item name="textBold">true</item> </style></resources>that's why we didn't declare namespace at resources element, it still work.
values/styles.xml
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar"> ... <item name="defaultButtonColor">@color/red</item> <item name="defaultButtonHeight">@dimen/dp_100</item></style>values/attrs.xml
<resources> <attr name="defaultButtonColor" format="reference" /> <attr name="defaultButtonHeight" format="reference"/></resources>values/colors.xml
<resources> <color name="red">#f00</color></resources>values/dimens.xml
<resources> <dimen name="dp_100">100dp</dimen></resources>Using
<Button android:layout_width="wrap_content" android:layout_height="?attr/defaultButtonHeight" android:text="Button" android:textColor="?attr/defaultButtonColor" />