Multiple Xamarin.Forms ActivityIndicator Colors

ActivityIndicatorDemoPage.cs

using System;
using Xamarin.Forms;

namespace FormsGallery
{
	class ActivityIndicatorDemoPage : ContentPage
	{
		public ActivityIndicatorDemoPage()
		{
			Label header = new Label
			{
				Text = "ActivityIndicator",
				FontSize = 40,
				FontAttributes = FontAttributes.Bold,
				HorizontalOptions = LayoutOptions.Center
			};

			ActivityIndicator activityIndicator01 = new ActivityIndicator
			{
				Color = Device.OnPlatform(Color.Black, Color.Default, Color.Default),
				IsRunning = true,
				VerticalOptions = LayoutOptions.CenterAndExpand
			};

			ActivityIndicator activityIndicator02 = new ActivityIndicator
			{
				Color = Color.Red,
				IsRunning = true,
				VerticalOptions = LayoutOptions.CenterAndExpand
			};

			ActivityIndicator activityIndicator03 = new ActivityIndicator
			{
				Color = Color.Blue,
				IsRunning = true,
				VerticalOptions = LayoutOptions.CenterAndExpand
			};
			ActivityIndicator activityIndicator04 = new ActivityIndicator
			{
				Color = Color.Green,
				IsRunning = true,
				VerticalOptions = LayoutOptions.CenterAndExpand
			};
			ActivityIndicator activityIndicator05 = new ActivityIndicator
			{
				Color = Color.Purple,
				IsRunning = true,
				VerticalOptions = LayoutOptions.CenterAndExpand
			};


			// Build the page.
			this.Content = new StackLayout
			{
				Children = 
				{
					header,
					activityIndicator01,
					activityIndicator02,
					activityIndicator03,
					activityIndicator04,
					activityIndicator05
				}
			};
		}
	}
}

Different Colors, based on Operating System / Platform
https://gist.github.com/mattregul/fe557b784946a80a4e3e#file-activityindicatordemopage-cs-L20

Creating a Red ActivityIndicator
https://gist.github.com/mattregul/fe557b784946a80a4e3e#file-activityindicatordemopage-cs-L27

This is a modified version of the ActivityIndicatorDemoPage inside the Xamarin-Forms/FormsGallery repository

You can find it here:

• https://github.com/xamarin/xamarin-forms-samples/tree/master/FormsGallery
• http://developer.xamarin.com/samples/xamarin-forms/FormsGallery/

Other Forms Samples:

• https://github.com/xamarin/xamarin-forms-samples
• http://developer.xamarin.com/samples/xamarin-forms/all/
• http://developer.xamarin.com/guides/cross-platform/xamarin-forms/
• http://developer.xamarin.com/guides/cross-platform/xamarin-forms/introduction-to-xamarin-forms/
• http://developer.xamarin.com/samples/tag/Xamarin.Forms/
• http://blog.xamarin.com/behaviors-in-xamarin.forms/

Forms XAML Samples:

• http://developer.xamarin.com/samples/xamarin-forms/XAMLSamples/
• https://github.com/xamarin/xamarin-forms-samples/tree/master/XAMLSamples
• http://developer.xamarin.com/guides/cross-platform/xamarin-forms/user-interface/xaml-basics/