记录一下系统默认 MaterialDesign效果 的Button 悬浮样式

路径 Sdk包：anim---》button_state_list_anim_material

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true" android:state_enabled="true">
        <set>
            <objectAnimator android:propertyName="translationZ"
                            android:duration="@integer/button_pressed_animation_duration"
                            android:valueTo="@dimen/button_pressed_z_material"
                            android:valueType="floatType"/>
            <objectAnimator android:propertyName="elevation"
                            android:duration="0"
                            android:valueTo="@dimen/button_elevation_material"
                            android:valueType="floatType"/>
        </set>
    </item>
    <!-- base state -->
    <item android:state_enabled="true">
        <set>
            <objectAnimator android:propertyName="translationZ"
                            android:duration="@integer/button_pressed_animation_duration"
                            android:valueTo="0"
                            android:startDelay="@integer/button_pressed_animation_delay"
                            android:valueType="floatType"/>
            <objectAnimator android:propertyName="elevation"
                            android:duration="0"
                            android:valueTo="@dimen/button_elevation_material"
                            android:valueType="floatType" />
        </set>
    </item>
    <item>
        <set>
            <objectAnimator android:propertyName="translationZ"
                            android:duration="0"
                            android:valueTo="0"
                            android:valueType="floatType"/>
            <objectAnimator android:propertyName="elevation"
                            android:duration="0"
                            android:valueTo="0"
                            android:valueType="floatType"/>
        </set>
    </item>
</selector>