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" 
			 x:Class="ButtonWithImage.MainPage"
			 Title="Button Image Sample"
			 BackgroundColor="White">
    <ContentPage.Resources>
        <ResourceDictionary>
            <OnPlatform x:Key="RefreshImage" x:TypeArguments="ImageSource">
                <OnPlatform.iOS>refresh.png</OnPlatform.iOS>
                <OnPlatform.Android>refresh_black_24dp.png</OnPlatform.Android>
                <OnPlatform.WinPhone>refresh_black_24dp.png</OnPlatform.WinPhone>
            </OnPlatform>
        </ResourceDictionary>
    </ContentPage.Resources>
    <StackLayout>
        <!-- ... -->
        <StackLayout VerticalOptions="End">
            <StackLayout IsVisible="{Binding NoConnection}" x:Name="ButtonStackLayout" Orientation="Horizontal" Spacing="10" Padding="10,10,10,10" BackgroundColor="#E3E3E3">
                <StackLayout HorizontalOptions="StartAndExpand"></StackLayout>
                <Label x:Name="ButtonLabel" BackgroundColor="#E3E3E3" Text="Retry" TextColor="Black" VerticalOptions="Center" HorizontalOptions="Center" />
                <Image x:Name="ButtonImage" BackgroundColor="#E3E3E3" WidthRequest="24" Source="{StaticResource RefreshImage}" VerticalOptions="Center" HorizontalOptions="Center" />
                <StackLayout HorizontalOptions="EndAndExpand"></StackLayout>
            </StackLayout>
        </StackLayout>
    </StackLayout>
</ContentPage>