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Binding custom dependency properties

I am having a problem with custom property dependency binding. We have: A custom user control with one dependency property and self-binding:

<UserControl x:Class="WpfApplication1.SomeUserControl"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
         mc:Ignorable="d" 
         d:DesignHeight="300" d:DesignWidth="300" DataContext="{Binding RelativeSource={RelativeSource Mode=Self}}">
<Grid>
    <Label>
        <Label.Template>
            <ControlTemplate>
                <Label Content="{Binding MyTest}"/>
            </ControlTemplate>
        </Label.Template>
    </Label>
</Grid>

... and control code:

public partial class SomeUserControl : UserControl
{
    public SomeUserControl()
    {
        InitializeComponent();
    }

    public static readonly DependencyProperty MyTestProperty = DependencyProperty.Register("MyTest", typeof(int), typeof(SomeUserControl));

    public int MyTest
    {
        get { return (int)GetValue(MyTestProperty); }
        set { SetValue(MyTestProperty, value); }
    }
}

I am trying to use this control with reference to some simple property of a simple model class:

<UserControl x:Class="WpfApplication1.AnotherUserControl"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:wpfApplication1="clr-namespace:WpfApplication1"
         mc:Ignorable="d" 
         d:DesignHeight="300" d:DesignWidth="300" DataContext="{Binding RelativeSource={RelativeSource Mode=Self}}">
<Grid>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="Auto"/>
        <ColumnDefinition Width="Auto"/>
    </Grid.ColumnDefinitions>
    <wpfApplication1:SomeUserControl MyTest="{Binding Path=Model.MyNum}" Grid.Column="0"/>
    <Label Content="{Binding Path=Model.MyNum}" Grid.Column="1"/>
</Grid>

... with code

public partial class AnotherUserControl : UserControl
{
    public MyModel Model { get; set; }
    public AnotherUserControl()
    {
        Model = new MyModel();
        Model.MyNum = 1231;
        InitializeComponent();
    }
}

... and model:

public class MyModel:INotifyPropertyChanged
{
    private int _myNum;

    public int MyNum
    {
        get { return _myNum; }
        set { _myNum = value; OnPropertyChanged("MyNum");}
    }

    public event PropertyChangedEventHandler PropertyChanged;

    [NotifyPropertyChangedInvocator]
    protected virtual void OnPropertyChanged(string propertyName)
    {
        PropertyChangedEventHandler handler = PropertyChanged;
        if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
    }
}

But the binding does not work. The stack has no compilation errors. Now the binding works with the statndart wpf label control (with the same model) and does not work with my custom control and custom property. Please help me understand the causes of this problem and solve it; Thanks)

+4
2

ElementName SomeUserControl.

<UserControl x:Class="WpfApplication1.SomeUserControl"
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
     xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
     mc:Ignorable="d" 
     d:DesignHeight="300" d:DesignWidth="300" 
     x:Name="uc">

<Grid>
    <Label>
        <Label.Template>
            <ControlTemplate>
                <Label Content="{Binding MyTest, ElementName=uc}"/>
            </ControlTemplate>
        </Label.Template>
    </Label>
</Grid>

, datacontext usercontrol /. WPF

+6

, : usercontrol- RelativeSource DataContext usercontrol, userControl DataContext.

        <wpfApplication1:SomeUserControl MyTest="{Binding Path=DataContext.Model.MyNum, RelativeSource={RelativeSource FindAncestor={x:Type UserControl}}}" Grid.Column="0"/>
+2

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