how to bind collection to custom control in wpf - wpf

Question

I am building a custom control and I want to pass a collection to it so that control display that collection, my code is as the following :
<gm:Calendar SubscriptionSource="{Binding Subscriptions}"></gm:Calendar>
and in Custom control "Calendar"
public static readonly DependencyProperty SubscriptionSourceProperty =
DependencyProperty.Register(
"SubscriptionSource",
typeof(ObservableCollection<Subscription>),
typeof(Calendar),
new FrameworkPropertyMetadata(new ObservableCollection<Subscription>()));
public ObservableCollection<Subscription> SubscriptionSource
{
get
{
return (ObservableCollection<Subscription>)GetValue(SubscriptionSourceProperty);
}
set
{
SetValue(SubscriptionSourceProperty, value);
}
}
I use in generic.xaml
<ItemsControl ItemsSource="{Binding SubscriptionSource}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<!--Box-->
<Border BorderBrush="Black" BorderThickness="1" Padding="0">
<Border Name="InnerBorder" BorderBrush="{Binding Path=Day, Converter={StaticResource DayBorderColorConverter}}" BorderThickness="2">
<Border.Style>
<Style TargetType="{x:Type Border}">
<Style.Triggers>
<!--Current Day-->
<DataTrigger Binding="{Binding IsToday}" Value="true">
<Setter Property="Border.Background">
<Setter.Value>
<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#FF1EA6C8" Offset="0"/>
<GradientStop Color="#FF0691B3" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</Border.Style>
<DockPanel>
<!--Day Number-->
<StackPanel Orientation="Horizontal" DockPanel.Dock="Top" FlowDirection="RightToLeft">
<TextBlock TextAlignment="Right" Text="{Binding Day.Date, Converter={StaticResource DateConverter}, ConverterParameter=DAY}" FontSize="12" Margin="5,5,5,5" >
<TextBlock.Style>
<Style TargetType="{x:Type TextBlock}">
<Style.Triggers>
<DataTrigger Binding="{Binding IsTargetMonth}" Value="false">
<Setter Property="TextBlock.Foreground" Value="Gray"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</TextBlock.Style>
</TextBlock>
</StackPanel>
<CheckBox IsEnabled="{Binding IsEnabled}" Style="{StaticResource DiscreteCheckBoxStyle}" />
</DockPanel>
</Border>
</Border>
</DataTemplate>
</ItemsControl.ItemTemplate>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid Rows="6" Columns="7" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
</ItemsControl>
I want to Bind Subscriptions observable collection to the calendar custom control so I can use the collection in the custom control, is there is away to do this?

Answer 1

If the ItemsControl is inside the ControlTemplate, then Change the {Binding SubscriptionSource} for {TemplateBinding SubscriptionSource}

Answer 2

My problem is now Solved thanks to #Luke Woodward and I just had another problem that I use the custom control inside usercontrol and that usercontrol was an item inside ListItem
I modified the binding expression
<gm:Calendar SubscriptionSource="{Binding Path=Subscriptions,Mode=TwoWay}" >
and the customcontrol is
static Calendar()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(Calendar), new FrameworkPropertyMetadata(typeof(Calendar)));
}
public ObservableCollection<SubscriptionDay> SubscriptionSource
{
get { return (ObservableCollection<SubscriptionDay>)GetValue(SubscriptionSourceProperty); }
set { SetValue(SubscriptionSourceProperty, value); }
}
public static readonly DependencyProperty SubscriptionSourceProperty =
DependencyProperty.Register("SubscriptionSource", typeof(ObservableCollection<SubscriptionDay>), typeof(Calendar), new FrameworkPropertyMetadata(new ObservableCollection<SubscriptionDay>()));
and in the Generic.xaml modified as #HighCore posted
<ItemsControl ItemsSource="{TemplateBinding SubscriptionSource}">
<ItemsControl.ItemTemplate>
<DataTemplate>......
and finally worked.
Thanks to #Luke Woodward and #HighCore