[android] How to show shadow around the linearlayout in Android?

i know this is way too late. but i had the same requirement. i solved like this

<android.support.v7.widget.CardView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:cardUseCompatPadding="true"
app:cardElevation="4dp"
app:cardCornerRadius="3dp" >

<!-- put whatever you want -->

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

you need to add dependency:

compile 'com.android.support:cardview-v7:25.0.1'