Toolbar's shadow on status bar for Lollipop

Put a LinearLayout in like this:

<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="match_parent"android:fitsSystemWindows="true"tools:context=".ui.activities.MainScreenActivity"><LinearLayout    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical">    <android.support.design.widget.AppBarLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:theme="@style/AppTheme.AppBarOverlay">        <android.support.v7.widget.Toolbar            android:id="@+id/toolbar"            android:layout_width="match_parent"            android:layout_height="?attr/actionBarSize"            android:background="?attr/colorPrimary"            app:popupTheme="@style/AppTheme.PopupOverlay" />    </android.support.design.widget.AppBarLayout>    <include layout="@layout/content_main_screen" /></LinearLayout></android.support.design.widget.CoordinatorLayout>

This shadow is part of windowContentOverlay on APIs below LOLLIPOP (on LOLLIPOP it's @null).

When you work with Toolbar widget the toolbar isn't part of window decor anymore so the shadow starts at the top of the window over the toolbar instead of below it (so you want the windowContentOverlay to be @null). Additionally you need to add an extra empty View below the toolbar pre-LOLLIPOP with its background set to a vertical shadow drawable (8dp tall gradient from #20000000 to #00000000 works best). On LOLLIPOP you can set 8dp elevation on the toolbar instead.

I tried all the other answers and none worked. What fixed it was adding this to the AppBarLayout:

    app:elevation="0dp"