textView设置按下和焦点改变时让字体颜色发生变化

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

 <TextView
        android:id="@+id/item_text"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:padding="2dip"
        android:textColor="@color/text_color_selector"
        android:textSize="12sp" />