How to show canvas on tapping on the image - windows-phone-8

Question

I have defined datatemplate in app.xaml
I have there an image
And in my custom page I have a canvas
How can I show this canvas on tapping on the image?
Here is my datatemplate in app.xaml
<DataTemplate x:Key="FlightInfoDataTemplate">
<Grid HorizontalAlignment="Stretch" Width="420">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="auto"/>
</Grid.ColumnDefinitions>
<!-- here are controls, which are not necessary now-->
<Image Tag="{Binding ID}" Source="/Images/bel_icon_2.png" Width="20" Height="20" Visibility="{Binding Path=Status, Converter={StaticResource StatusToVisibilityConverter}}" />
<!--***********-->
</Grid>
</DataTemplate>
Here is my canvas which is defined in MainPage.xaml
<Canvas x:Name="AddReminderDialog" HorizontalAlignment="Center" Height="280" Width="260"
VerticalAlignment="Center" Background="Transparent" Margin="110,178,110,238" Visibility="Collapsed">
<TextBlock Foreground="Yellow" Text="Напомнить" HorizontalAlignment="Center" Canvas.Left="78" Canvas.Top="28" />
<Button Name="btn1HourBef" BorderThickness="0" Background="Black" Content="За час" Width="260" FontSize="15" Height="60" Margin="0,70,0,0"/>
<Button Name="btn30MinBef" BorderThickness="0" Background="Black" Content="За 30 минут" Width="260" FontSize="15" Height="60" Margin="0,130,0,0"/>
<Button Name="btn10MinBef" BorderThickness="0" Background="Black" Content="По прилету/вылету" Width="260" FontSize="15" Height="60" Margin="0,190,0,0"/>
</Canvas>
How can I make it visible on tapping on the image?

Answer 1

Edit - canvas was meant to be used as a notification, and preferably reusable on several pages:
Per comments, it became clear the intention of the canvas was to provide a notification message. Something suitable for the concept of a dismissible popup. There already is a System.Windows.Controls.Primitives.Popup class in the framework.
Example:
In App.xaml:
<DataTemplate x:Key="FlightInfoDataTemplate">
...
<Image Tag="{Binding ID}" Source="/Images/bel_icon_2.png" Width="20" Height="20" Visibility="{Binding Path=Status, Converter={StaticResource StatusToVisibilityConverter}}" Tap="Image_Tap"/>
...
</DataTemplate>
<ControlTemplate x:Key="AddReminderDialog">
<Canvas HorizontalAlignment="Center" Height="280" Width="260" VerticalAlignment="Center" Background="WhiteSmoke" Margin="110,178,110,238">
<TextBlock Foreground="Black" Text="Hello" HorizontalAlignment="Center" Canvas.Left="78" Canvas.Top="28" />
<Button Name="btn1HourBef" BorderThickness="0" Background="Black" Content="За час" Width="260" FontSize="15" Height="60" Margin="0,70,0,0"/>
<Button Name="btn30MinBef" BorderThickness="0" Background="Black" Content="За 30 минут" Width="260" FontSize="15" Height="60" Margin="0,130,0,0"/>
<Button Name="btn10MinBef" BorderThickness="0" Background="Black" Content="По прилету/вылету" Width="260" FontSize="15" Height="60" Margin="0,190,0,0"/>
</Canvas>
</ControlTemplate>
In App.xaml.cs:
public partial class App : Application
{
private Popup popup = new Popup();
...
private void Image_Tap(object sender, System.Windows.Input.GestureEventArgs e)
{
var image = sender as Image;
var modelItem = image.DataContext;
const double width = 200;
const double height = 100;
var content = new ContentControl(){Width = width, Height = height, Background = new SolidColorBrush(Colors.Purple)};
content.Template = (ControlTemplate) Resources["AddReminderDialog"];
content.DataContext = modelItem; // you should define bindings in the ControlTemplate.
popup.Child = content;
popup.Height = height;
popup.Width = width;
popup.VerticalOffset = Application.Current.RootVisual.RenderSize.Height / 2 - height / 2;
popup.HorizontalOffset = Application.Current.RootVisual.RenderSize.Width / 2 - width / 2;
popup.IsOpen = true;
}