button 按下时改变字体颜色

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true" android:color="#000000"/> 黑色
<item android:state_focused="true" android:color="#ffffff"/>
<item android:color="#ffffff" />
</selector>

<Button
android:id="@+id/otg_tab"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="12345"
android:textColor="@drawable/button_text_selector"
>
</Button>