On this exemple, NativeScript dont change the text color from title bar, and title tabs bar.
<Page.actionBar>
<ActionBar title="Temas" style="background-color:blue;color:#fff">
</ActionBar>
</Page.actionBar>
Or
<TabView>
<TabView.items>
<TabViewItem title="Questions" style="background-color:blue;color:#fff">
<TabViewItem.view>
<GridLayout>
<ListView items="{{ items }}">
<ListView.itemTemplate>
<Label cssClass="cat" text="{{ question }}" textWrap="true" />
</ListView.itemTemplate>
</ListView>
</GridLayout>
</TabViewItem.view>
</TabViewItem>
</TabView>
On this exemple, NativeScript dont change the text color from title bar, and title tabs bar.
Or