Set Toolbar Icon Colour Programmatically

How can I set the colour of icons (home and overflow menu icon) in a Toolbar/AppBarLayout programmatically?

I want to change the toolbar's colour scheme for a single fragment in an activity. Setting the AppBarLayout's background to a light colour (e.g. light gray with appBarLayout.setBackgroundResource(..);) results in white icons and a white title which are barely visible.

Its layout is as follows:

<android.support.design.widget.AppBarLayout
    android:id="@+id/appbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:fitsSystemWindows="true">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:theme="@style/ToolbarStyle"
        app:layout_scrollFlags="scroll|enterAlways"/>

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

Solution found