<RadioButton
    android:id="@+id/radio_button0"
    android:layout_height="fill_parent"
    android:layout_marginTop="2.0dip"
    android:drawableTop="@drawable/icon"
    android:tag="radio_button0"
    android:textColor="@color/color_radiobutton"
android:background="@color/radio_group_selector"
    android:checked="true"  //设置为已选中，则显示的效果为选中的字体颜色
    android:text="按钮1号" />
  <RadioButton
    android:id="@+id/radio_button1"
    android:layout_height="fill_parent"
    android:layout_marginTop="2.0dip"
    android:tag="radio_button1"
    android:drawableTop="@drawable/icon"
android:background="@color/radio_group_selector"
    android:textColor="@color/color_radiobutton"
    android:text="按钮2号" />

android:textColor="@color/color_radiobutton"
android:background="@color/radio_group_selector"

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
  <item android:state_checked="true" android:color="@color/green"/>
  <!-- not selected -->
  <item android:state_checked="false" android:color="@color/white"/>
</selector>

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android" >
  <item android:state_checked="true" android:drawable="@color/green" ></item>
  <item android:state_checked="false" android:drawable="@color/black"></item>
</selector>

<?xml version="1.0" encoding="utf-8"?>
<resources>
  <color name="black">#000000</color>
  <color name="white">#FFFFFF</color>
  <color name="green">#00FF00</color>
</resources>