Setting CollapsingToolbarLayout image programmatically
<p>I am using a <code>ScrollingActivity</code> which comes with a <code>CollapsingToolbarLayout</code>. I want to add an <code>ImageView</code> to this layout, and be able to toggle the image programmatically, but it doesn't seem to be doing anything.</p>

<p>XML of my layout:</p>

<pre><code>    &lt;android.support.design.widget.CollapsingToolbarLayout
        android:id="@+id/toolbar_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fitsSystemWindows="true"
        app:layout_scrollFlags="scroll|exitUntilCollapsed"&gt;

        &lt;android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            app:layout_collapseMode="pin"
            app:popupTheme="@style/AppTheme.PopupOverlay" /&gt;

        &lt;ImageView
            android:id="@+id/header_logo"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scaleType="center"
            android:layout_gravity="center"
            app:layout_collapseMode="parallax"
            /&gt;

    &lt;/android.support.design.widget.CollapsingToolbarLayout&gt;
</code></pre>

<p>When I try to do something like the following, on an event:</p>

<pre><code>ImageView im = (ImageView)findViewById(R.id.toolbar_layout);
im.setBitmap(image_here);
</code></pre>

<p>But when I trigger this event, nothing happens. I know that my image is being parsed correctly because I'm not getting any exceptions from it, in fact; I'm not getting any exceptions at all throughout this process. Am I doing something wrong here? Is there a way to refresh this Toolbar to update the image?</p>