Elevation not working on a LinearLayout

Question

After searching for a solution, I didn't find any to solve my problem.

I have some elevation which produces a shadow on a big part of my app.
But in a particular place, I'm not able to make it work.
(It's where I put an arrow on the picture below)

The white area below the toolbar is a Fragment which displays a LinearLayout

layout:

<LinearLayout     android:id="@+id/panelAddress"     xmlns:android="http://schemas.android.com/apk/res/android"     android:layout_width="match_parent"     android:layout_height="wrap_content"     android:background="@drawable/button_flat_white"     android:elevation="10dp"     android:orientation="vertical"     android:padding="20dp"     >   //some content </LinearLayout> 

The parent of the Fragment :

<android.support.v4.widget.DrawerLayout     android:id="@+id/drawerLayout"     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"     android:orientation="vertical"     >      <LinearLayout         android:layout_width="match_parent"         android:layout_height="match_parent"         android:orientation="vertical">          <include             android:id="@+id/custom_toolbar"             layout="@layout/toolbar"/>          <RelativeLayout             android:id="@+id/mapLayout"             android:layout_width="match_parent"             android:layout_height="match_parent">              <fragment                 android:id="@+id/map"                 class="com.google.android.gms.maps.SupportMapFragment"                 android:layout_width="match_parent"                 android:layout_height="match_parent"/>              <FrameLayout                 android:id="@+id/fragment_container_top"                 android:layout_width="match_parent"                 android:layout_height="wrap_content"                 android:layout_alignParentTop="true"                 />              <FrameLayout                 android:id="@+id/fragment_container_bottom"                 android:layout_width="match_parent"                 android:layout_height="wrap_content"                 android:layout_alignParentBottom="true"/>          </RelativeLayout>      </LinearLayout>  </android.support.v4.widget.DrawerLayout> 

Do you have an idea about why I don't get my elevation?

Answer 1

As described here https://stackoverflow.com/a/27518160/2481494 there are several requirements so that the shadow is drawn:

• Space for the shadow in the parents view Group. As bleeding182 mentioned, padding can cause the shadow to be clipped:

  (Do NOT use a padding. A padding on the framelayout will also cut the shadow off)

  However, this can be fixed with android:clipToPadding="false" in the parent.

• The elevated view needs to have a background to cast a shadow. Without information about your @drawable/button_flat_white I can't tell whether this is a problem in your case.

To solve your problem you should modify your FrameLayout like this:

<FrameLayout         android:id="@+id/fragment_container_top"         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:layout_alignParentTop="true"          android:clipToPadding="false"         android:paddingBottom="10dp"/> 

To check whether your @drawable/button_flat_white causes any problems try to change the background of your LinearLayout to a simple color temporarily:

<LinearLayout     android:id="@+id/panelAddress"     xmlns:android="http://schemas.android.com/apk/res/android"     android:layout_width="match_parent"     android:layout_height="wrap_content"     android:elevation="10dp"     android:orientation="vertical"     android:padding="20dp"      android:background="#fff">   //some content </LinearLayout>