How to bind to a WPF dependency property to window?

Question

i create a dependency property to close a view from view model,

dependencyProperty:

  public static class WindowBehaviors 
  {      
     public static readonly DependencyProperty IsOpenProperty =
              DependencyProperty.RegisterAttached("IsOpen"
             , typeof(bool),
             typeof(WindowBehaviors),
             new UIPropertyMetadata(false, IsOpenChanged));

    private static void IsOpenChanged(DependencyObject   obj,DependencyPropertyChangedEventArgs args)
    {
        Window window = Window.GetWindow(obj);

        if (window != null && ((bool)args.NewValue))
            window.Close();
    }


    public static bool GetIsOpen(Window target)
    {
        return (bool)target.GetValue(IsOpenProperty);
    }

    public static void SetIsOpen(Window target, bool value)
    {
        target.SetValue(IsOpenProperty, value);
    }
}

and use it in my xaml like this:

<window
...
Command:WindowBehaviors.IsOpen="True">

it work's fine,but when i want to bind it to a property in viewModel,it dosen't work,and i guess,it dosen't work because i define the resource later in xaml.

in xaml:

 <Window.Resources>
     <VVM:myVieModel x:Key="myVieModel"/>
 </Window.Resources>

and i don't know what should i do,where should i put this:

Command:WindowBehaviors.IsOpen="{binding Isopen}"

try this `Command:WindowBehaviors.IsOpen="{binding Isopen,Mode=TwoWay}"` maybe your binding value is incorrect. `o` shown lowercase. — ebattulga, Mar 05 '12 at 10:47
no,it's not the problem.i cant bind anything before resource definition,for example for title i have to put this after resource definition: — mahboub_mo, Mar 05 '12 at 10:54

score 0 · Answer 1 · answered Mar 05 '12 at 11:09

0

    public MainWindow()
            {
                InitializeComponent();

// DO THIS
                this.DataContext = Resources["myVieModel"];

            }

answered Mar 05 '12 at 11:09

ebattulga

10,774
20
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116

thanks.i'll give it a try,but i don't want to write in the code behind! – mahboub_mo Mar 05 '12 at 11:16
it doesn't work,it should have an easy solution.what's wrong? – mahboub_mo Mar 05 '12 at 12:24

score 0 · Answer 2 · edited May 23 '17 at 11:55

0

You need to bind the data context for the scope where your binding is in. Usually this is fairly high up in your XAML, usually the first element in your form or control.

In your case, the data context beeing a static resource the folllowing should work:

<grid DataContext="{StaticResource myVieModel}">
    <!-- the code with the binding goß into here -->
</grid>

Actually this is the same as ebattulga suggests, just the XAML way (no code behind).

edited May 23 '17 at 11:55

Community

1
1

answered Mar 05 '12 at 23:51

AxelEckenberger

16,628
3
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70

thanks,but i want to bind to the property of window not grid's children!what should i write here?!!! `` – mahboub_mo Mar 06 '12 at 05:42

score 0 · Accepted Answer · answered Mar 06 '12 at 09:13

Thanks for your helps,i fixed it and here is my solution, i used to use MVVMToolkit but now i'm useing MVVMlight and as you know in MVVMLight,we just define Application Resources Once in App.xaml.so we can bind all the window's properties simply,hope this can help some people who has the same problem!!

app.xaml

  <Application.Resources>
    <!--Global View Model Locator-->
    <vm:ViewModelLocator x:Key="Locator"
                         d:IsDataSource="True" />
  </Application.Resources>

and in the window(view)

DataContext="{Binding DefaultSpecItemVM, Source={StaticResource Locator}}"

and it works perfect.:D

How to bind to a WPF dependency property to window?

3 Answers3