“android:elevation=” doesn’t work on devices pre-Lollipop with compile API21

UPDATED ::

1. Best Practice to do that is

   <android.support.v7.widget.CardView>
       <YourLayout>
   </android.support.v7.widget.CardView>
   

   and add library for cardview

   dependencies {
      ...
      compile 'com.android.support:cardview-v7:21.0.+'
    }
   

2. On Pre-Lollipop you can use this drawable

   android:background=”@android:drawable/dialog_holo_light_frame”

   it will give you the look of elevation

3. you can create your own like this

   <?xml version="1.0" encoding="utf-8"?>
   <layer-list xmlns:android="http://schemas.android.com/apk/res/android">
   
   <item>
   <shape android:shape="rectangle">
       <solid android:color="#BDBDBD"/>
       <corners android:radius="5dp"/>
   </shape>
   </item>
   
   <item
   android:left="0dp"
   android:right="0dp"
   android:top="0dp"
   android:bottom="2dp">
   <shape android:shape="rectangle">
       <solid android:color="#ffffff"/>
       <corners android:radius="5dp"/>
   </shape>
   </item>
   </layer-list>
   

reference