Cannot bind between MyCombobox and the binding property
===

I create a own ComboBoxItem. Here I have simplified the code. The ComboBoxItem contain a CheckBox.


ComboBoxItem Control xaml:

    <ComboBoxItem x:Class="WpfApplication1.MyCombobox"
    			 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    			 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    			 Height="50"
    			 Width="200">
    	<!-- ... -->
    	<StackPanel>
    		<CheckBox IsChecked="{Binding Path=IsCheckboxChecked}" IsEnabled="{Binding Path=IsCheckboxEnabled}">
    			<CheckBox.LayoutTransform>
    				<ScaleTransform ScaleX="1" ScaleY="1" />
    			</CheckBox.LayoutTransform>
    		</CheckBox>
    		<!-- ... -->
    	</StackPanel>
    </ComboBoxItem>
    
ComboBoxItem Control c# (code behind)

    public partial class MyCombobox
    {
    	public MyCombobox()
    	{
    		InitializeComponent();
    		DataContext = this;
    
    		//Defaults
    		IsCheckboxChecked = false;
    		IsCheckboxEnabled = true;
    		
    		//...
    	}
    
    	//...
    	
    	public string Text { get; set; }
    
    	public bool IsCheckboxChecked { get; set; }
    
    	public bool IsCheckboxEnabled { get; set; }
    	
    	//...
    }
    
and I include it so:

    <WpfApplication1:MyCombobox IsCheckboxChecked="{Binding Path=IsMyCheckBoxChecked, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" IsCheckboxEnabled="{Binding Path=IsMyCheckBoxEnabled, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}" Text="Write your Text here" />

When I run my application I get this error:

> A fatal error occurred: a 'Binding' cannot be set on the
> 'IsCheckboxChecked' property of type 'MyCombobox'. A 'Binding' can
> only be set on a Dependency Property of a DependencyObject

What do I make wrong?