Android 如何制作主题样式的选择器按钮

我想让主题的风格像选择器一样

<selector xmlns:android="http://schemas.android.com/apk/res/android">

<item android:state_pressed="true" android:drawable="@color/color_blue_pressed"/> <!-- pressed -->
<item android:state_focused="true" android:drawable="@color/color_blue_focused"/> <!-- focused -->
<item android:drawable="@color/color_blue"/> <!-- default -->

我认为这是形式。但我不知道该怎么把颜色压成蓝色

 <style name="button" parent="@android:style/Widget.Button">
    <item name="android:gravity">center_vertical|center_horizontal</item>
    <item name="android:textColor">#FFFFFFFF</item>
    <item name="android:shadowColor">#FF000000</item>
    <item name="android:shadowDx">0</item>
    <item name="android:shadowDy">-1</item>
    <item name="android:shadowRadius">0.2</item>
    <item name="android:textSize">16dip</item>
    <item name="android:textStyle">bold</item>
    <item name="android:background">@drawable/button</item>
    <item name="android:focusable">true</item>
    <item name="android:clickable">true</item>
</style>

中心|垂直|中心|水平
#FFFFFFFF
#FF000000
0
-1
0.2
16倾角
大胆的
@可拉拔/按钮
真的
真的

我希望你们中有人能帮助我

你可以用什么颜色

要创建可绘制形状，请使用：-

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle" >

<corners android:radius="5dp" />

<gradient
    android:angle="270"
    android:endColor="#FFFF0000"
    android:startColor="FFFFFF00" />

</shape>

<item android:state_pressed="false"><shape>
        <solid android:color="@color/hoverblue" />
    </shape></item>
<item android:state_pressed="true"><shape>
        <solid android:color="@color/blue" />
    </shape></item>

<?xml version="1.0" encoding="utf-8"?>

<item android:drawable="@drawable/selector_cancel_btn_pressed" android:state_pressed="true"></item>
<item android:drawable="@drawable/selector_cancel_btn_over" android:state_focused="true"></item>
<item android:drawable="@drawable/selector_cancel_btn_normal"></item>

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle" >

<corners android:radius="5dp" />

<gradient
    android:angle="270"
    android:endColor="#FFFF0000"
    android:startColor="FFFFFF00" />

</shape>