Android elevation property not working

Question

Since upgrading to SDK 21 I've been trying to use the elevation property but it never seems to work.

I want to elevate a frame above others so I'm setting the following

android:elevation="4dp"

but there's no sign of shadow. I've tried buttons and framelayouts but not got any elevation

So here's the full tag

    <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:id="@+id/panel_card"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="#ffffff"
    android:elevation="4dp"
    >

Am I missing something else I need to add

Answer 1

Make sure that the background for the container holding the FrameLayout is not transparent.

Answer 2

According to this Z = Elevation + TranslationZ

so try this:

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:card_view="http://schemas.android.com/apk/res-auto"
  android:id="@+id/panel_card"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:background="#ffffff"
  android:elevation="4dp"
  android:translationZ="4dp">