Hello!

I have two UserControls ("UserControlParentView" and "UserControlChildView") with MVVM pattern implemented in both controls. Parent control is a container for Child control and child control's property should be updated by data binding from Parent control in order to show/hide some check box inside Child control.

Parent Control Description

UserControlParentViewModel has property:

    private bool isShowCheckbox = false;
    public bool IsShowCheckbox
    {
        get { return isShowCheckbox; }
        set { isShowCheckbox = value; NotifyPropertyChanged("IsShowCheckbox");  }
    }

UserControlParentViewModel - how I set DataContext of Parent control:

    public UserControlParentView()
    {
        InitializeComponent();

        this.DataContext = new UserControlParentViewModel();
    }        

UserControlParentView contains toggle button (in XAML), bound to UserControlParentViewModel's property IsShowCheckbox

<ToggleButton Grid.Column="1" IsChecked="{Binding IsShowCheckbox, Mode=TwoWay}"></ToggleButton>

Also Parent control contains instance of child element (somewhere in XAML)

<local:UserControlChildView IsCheckBoxVisible="{Binding IsShowCheckbox}" ></local:UserControlChildView>

so property in child control should be updated when user togggle/untoggle button. Child control contains Boolean property to be updated from parent control, but nothing happened! Breakpoint never fired!

Property in UserControlChildView that should be updated from Parent control (here I plan to make chechBox visible/hidden in code behind):

    public bool IsCheckBoxVisible
    {
        get { return (bool)GetValue(IsCheckBoxVisibleProperty); }
        set { SetValue(IsCheckBoxVisibleProperty, value); }
    }
    // Using a DependencyProperty as the backing store for IsCheckBoxVisible.  This enables animation, styling, binding, etc...
    public static readonly DependencyProperty IsCheckBoxVisibleProperty =
        DependencyProperty.Register("IsCheckBoxVisible", typeof(bool), typeof(TopMenuButton), new PropertyMetadata(false));

So the question is - what I'm doing wrong? Why child's property is never updated? BTW - there is no any binding error warnings in Output window...