Android 5.0 android:elevation 如果给button设置效果

看到android5.0版本中提供了  elevation  的功能，我在SDK Manager 下载了 Android 5.0  例子代码，看了下  ElevationBasic 例子，展示了2个view对象，一个圆形一个矩形，圆形设置了 android:elevation  =  30dp，具体例子如下

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


< FrameLayout  xmlns:android = "http://schemas.android.com/apk/res/android"
             xmlns:tools = "http://schemas.android.com/tools"
             android:layout_width = "match_parent"
             android:layout_height = "match_parent" >
    < View
            android:id = "@+id/floating_shape"
            android:layout_width = "80dp"
            android:layout_height = "80dp"
            android:layout_marginRight = "40dp"
            android:background = "@drawable/shape"
            android:elevation = "30dp"
            android:layout_gravity = "center" />
    < View
            android:id = "@+id/floating_shape_2"
            android:layout_width = "80dp"
            android:layout_height = "80dp"
            android:layout_marginLeft = "25dp"
            android:background = "@drawable/shape2"
            android:layout_gravity = "center" />
FrameLayout >

 

 

在 Nexus 9 中跑这里例子，得到的效果如下

 

如果我把 组件换成按钮Button，移除掉按钮的其他属性，就不会显示 elevation  效果，如下
默认主题的按钮样式中包含了  android:elevation 和 android:translationZ 属性，你可以移除掉默认的属性动画，并设置你自己的android:stateListAnimator 属性
如下代码

< Button
    ...

    android:stateListAnimator = "@null"  />

< Button
    ...

    android:stateListAnimator = "@anim/my_animator"  />

 

默认的动画（animator）在button_state_list_anim_material.xml定义。这里是一个展示状态下不可用，按钮处于点击状态的例子

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

    < 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 >
    ...

selector >

原文地址：http://www.itmmd.com/201412/240.html
该文章由  萌萌的IT人  整理发布,转载须标明出处。