Android "app:titleTextColor" Doesn't Work in MaterialToolbar within CollapsingToolbarLayout

Question

<com.google.android.material.appbar.CollapsingToolbarLayout
    android:id="@+id/collapsingToolbarLayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:contentScrim="@color/purple_500"
    app:layout_scrollFlags="scroll|exitUntilCollapsed">

    <ImageView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scaleType="centerCrop"
        android:src="@drawable/sam" />

    <com.google.android.material.appbar.MaterialToolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?actionBarSize"
        app:title="Sam Chen"
        app:titleTextColor="@color/white"/>    //<- here, doesn't work

</com.google.android.material.appbar.CollapsingToolbarLayout>

Result:

And collapsed:

Answer 1

Here is my solution for my case, I just need the title and options menu icon to be white:

<com.google.android.material.appbar.CollapsingToolbarLayout

    ...

    android:theme="@style/ThemeOverlay.MaterialComponents.Dark.ActionBar">

For customizing color of title and options menu icon can read this: How to change the Text color of collapsing toolbar and the back button color of collapsing toolbar in android

Answer 2

<com.google.android.material.appbar.CollapsingToolbarLayout
            ...
            app:collapsedTitleTextColor="@android:color/white"
            app:expandedTitleTextColor="@android:color/white">

Answer 3

For anyone else who is struggling with the same issue, I have solved this with the following, I believe the issue was that I was trying to call the bindings twice, instead of creating one variable and controlling it all there.

 Are you human?<br><select data-bind="value: selectedChoice">
  <option value="none">Select answer</option>
  <option value="yes">Yes</option>
  <option value="no">No</option>

</select>
<p data-bind="visible: selectedChoice() === 'yes'">
  Are you employed?<br>
  <select data-bind="value: currentSelect">
    <option value="blank">none</option>
    <option value="form">show form</option>
    <option value="sorry">Something else</option>
  </select></p>
<br><br>


<p data-bind="visible:currentSelect() === 'blank'"> </p>
<p data-bind="visible:currentSelect() === 'form'">Hello, now display the sign up form</p>
<p data-bind="visible:currentSelect() === 'sorry'">Goodbye</p>

 <script> 
var viewModel = {
  
    selectedChoice: ko.observable("none"),
    currentSelect: ko.observable("none")

};


ko.applyBindings(viewModel);

</script>