Xamarin : Remove SupportAppBar Shadow

Question

I'm trying to remove my AppBar Shadow. I read a lot of posts, tried few tips but nothing worked.

Here is my code :

activity_main.axml :

    <android.support.design.widget.AppBarLayout
      android:id="@+id/appbar"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
      android:fitsSystemWindows="true" >

    <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/ThemeOverlay.AppCompat.Light"
        app:layout_scrollFlags="scroll|enterAlways" />

  </android.support.design.widget.AppBarLayout>

I tried adding app:elevation="0dp" in AppBarLayout, it makes the AppBar full transparent, but hamburger button is still working even if it's not displayed.

Adding elevation inside the toolbar isn't doing anything.

Adding 0dp in my theme is also making my AppBar transparent.

In my C# code, SupportActionBar.Elevation = 0; isn't doing anything too.

Can you help me please ? Thanks a lot.