MainPage.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:components="clr-namespace:AsyncButtonApp.Components"
             xmlns:vm="clr-namespace:AsyncButtonApp.ViewModels"
             x:Class="AsyncButtonApp.Views.MainPage"
             Title="Main Page">
    <ContentPage.BindingContext>
        <vm:MainPageViewModel />
    </ContentPage.BindingContext>
    <ContentPage.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="/AsyncButtonControlTemplateResourceDictionary.xaml" />
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </ContentPage.Resources>
    <ContentPage.Content>
        <StackLayout BackgroundColor="White">
            <components:AsyncButtonView ControlTemplate="{StaticResource AsyncButtonControlTemplate}"
                                  HorizontalOptions="CenterAndExpand" VerticalOptions="CenterAndExpand" Padding="0"
                                  ButtonCornerRadius="8"
                                  ButtonHasShadow="True" ButtonClippedToBounds="True"
                                  ButtonBackgroundColor="#3F51B5"
                                  ButtonTextColor="White"
                                  ButtonText="Fetch Data"
                                  IsFetching="{Binding IsFetching}" FetchCommand="{Binding FetchCommand}" />
        </StackLayout>
    </ContentPage.Content>
</ContentPage>