DatePickerDisabledStatesGallery.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
			xmlns:windowsSpecific="clr-namespace:Xamarin.Forms.PlatformConfiguration.WindowsSpecific;assembly=Xamarin.Forms.Core"
			xmlns:androidSpecific="clr-namespace:Xamarin.Forms.PlatformConfiguration.AndroidSpecific;assembly=Xamarin.Forms.Core"
			xmlns:iosSpecific="clr-namespace:Xamarin.Forms.PlatformConfiguration.iOSSpecific;assembly=Xamarin.Forms.Core"
             x:Class="Xamarin.Forms.Controls.GalleryPages.VisualStateManagerGalleries.DatePickerDisabledStatesGallery"
			Title="DatePicker Disabled States Gallery">

	<ContentPage.Resources>
		<ResourceDictionary>

			<Style TargetType="DatePicker" x:Key="CustomDisabledState">
				<Setter Property="VisualStateManager.VisualStateGroups">
					<VisualStateGroupList>
						<VisualStateGroup x:Name="CommonStates">
							<VisualState x:Name="Normal" />
							<VisualState x:Name="Disabled">
								<VisualState.Setters>
									<Setter Property="TextColor" Value="Red" />
									<Setter Property="BackgroundColor" Value="Purple" />
								</VisualState.Setters>
							</VisualState>
						</VisualStateGroup>
					</VisualStateGroupList>
				</Setter>
			</Style>

			<Style TargetType="DatePicker" x:Key="DefaultInInitialState">
				<Setter Property="VisualStateManager.VisualStateGroups">
					<VisualStateGroupList>
						<VisualStateGroup x:Name="CommonStates">
							<VisualState x:Name="Normal" />
							<VisualState x:Name="Disabled">
								<VisualState.Setters>
									<Setter Property="TextColor" Value="Green" />
									<Setter Property="BackgroundColor" Value="Black" />
								</VisualState.Setters>
							</VisualState>
						</VisualStateGroup>
					</VisualStateGroupList>
				</Setter>
			</Style>

		</ResourceDictionary>
	</ContentPage.Resources>

	<ContentPage.Content>
		<ScrollView VerticalOptions="Fill" HorizontalOptions="Fill">
			<StackLayout>

				<!-- Not using the VSM at all; should exhibit pre-VSM default behavior -->
				<Label Text="The DatePicker below uses the current XF defaults; when IsEnabled is false, it uses the default native colors for the control. (Legacy Color Behavior)"/>
				<DatePicker x:Name="Picker0" TextColor="Blue" BackgroundColor="Bisque" >
				</DatePicker>
				<Button Text="Toggle IsEnabled" x:Name="Button0" Clicked="Button0_OnClicked" />

				<!-- Legacy Color Behavior turned off by the PlatformSpecific; ignores states entirely and uses 
					whatever colors are manually set for it -->
				<Label Text="The DatePicker below has the Legacy Color Behavior disabled; it will stick with whatever colors are set, regardless of state"/>
				<DatePicker x:Name="Picker1" TextColor="Blue" BackgroundColor="Bisque" 
							androidSpecific:VisualElement.IsLegacyColorModeEnabled="False"
							windowsSpecific:VisualElement.IsLegacyColorModeEnabled="False"
							iosSpecific:VisualElement.IsLegacyColorModeEnabled="False">
				</DatePicker>
				<Button Text="Toggle IsEnabled" x:Name="Button1" Clicked="Button1_OnClicked" />

				<!-- Disabled colors fully managed by the VSM -->
				<Label Text="The DatePicker below uses the VSM to customize the colors for the disabled state." />
				<DatePicker x:Name="Picker2" Style="{StaticResource CustomDisabledState}" TextColor="Green" 
							BackgroundColor="Beige">
				</DatePicker>
				<Button Text="Toggle IsEnabled" x:Name="Button2" Clicked="Button2_OnClicked" />

				<!-- This section verifies that the default colors for a DatePicker's text is cached and can be reverted to -->
				<Label Text="This DatePicker uses Color.Default for the intial text/background, and colors from the VSM when disabled."/>
				<DatePicker x:Name="Picker3" Style="{StaticResource DefaultInInitialState}" TextColor="Default" 
							BackgroundColor="Default">
				</DatePicker>
				<Button Text="Toggle IsEnabled" x:Name="Button3" Clicked="Button3_OnClicked" />
			</StackLayout>
		</ScrollView>
	</ContentPage.Content>
</ContentPage>