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Closing ChildWindow In MVVM by Using Attached Property

Posted By: Asim Sajjad Posted Date: June 19, 2011 Points: 2 Category :Silverlight

In this post I will show you how to close the ChildWindow of Silverlight using Attached property in MVVM. Let us start with the example code. For this example I have created Silverlight project of template "Silverlight Navigation with Accent Color" application. I have added new ChildWindow in the view folder with the name UserInputForm and then UserInputFormViewModel in the ViewModel folder which is the used to set as the DataContext of the UserInputForm.

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Setting an attached property by a Setter element?

I have the fragment below as contents of a <Grid> element. The idea is that if the checkbox is checked the <TreeView> element should only span one instead of two columns. When I check the checkbox the background of the treeview turns red, but the treeview continues to span 2 instead of 1 column. It's a bit like the attached property Grid.ColumnSpan does not get assigned by the <Setter Property="Grid.ColumnSpan" Value="1"/> at all. What should I do in order to achieve what I want?Best regards,Henrik Dahl ÃÂ <TreeView ÃÂ ÃÂ x:Name="Blas" ÃÂ ÃÂ ItemsSource="{Binding Path=BlasRoot.Children}" d:LayoutOverrides="Width" Margin="0,0,0,8" Grid.Column="0" Grid.ColumnSpan="2"> ÃÂ ÃÂ <TreeView.Style> ÃÂ ÃÂ ÃÂ ÃÂ ÃÂ <Style> ÃÂ ÃÂ ÃÂ ÃÂ ÃÂ ÃÂ ÃÂ ÃÂ <Style.Triggers> <DataTrigger Binding="{Binding ElementName=chkPosition, Path=IsChecked}" Value="True"> ÃÂ ÃÂ <Setter Property="Grid.ColumnSpan" Value="1"/> ÃÂ ÃÂ <Setter Property="TreeView.Background" Value="Red"/> </DataTrigger> ÃÂ ÃÂ ÃÂ ÃÂ ÃÂ ÃÂ ÃÂ ÃÂ </Style.Triggers> ÃÂ ÃÂ ÃÂ ÃÂ ÃÂ </Style> ÃÂ ÃÂ </TreeView.Style> </TreeView> <CheckBox HorizontalAlignment="Left" Margin="-50,0,0,0" x:Name="chkPosition" VerticalAlignment="Top" Content="

How do I automaticaly change one property based on another with MVVM?

I have a grid connected to a ViewModel class with two properties, public Address SelectedAddress and public ObservableCollection<Address> Addresses.

Address has, among other things, int? PersonID and int? CompanyID. My validation code in the Model checks that one of them is filled, but not both.

How do I set up code in the grid or ViewModel so that whenever PersonID is filled, CompanyID is automatically set to null, and the other way?

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I am working a project that has several different controls that I am trying to use an attached property to dictate whether or not to perform a recalculation operation if changed. I am using what I thought was the standard pattern for the creating of an AP.

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    {
        public static readonly DependencyProperty PerformRecalcProperty = DependencyProperty.RegisterAttached(
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          typeof(Boolean),
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Hi,

I've written a workflow level ErrorMessage as an attached property on the root workflow activity, at design time. I made the attached property for ErrorMessage written as an InArgument (to support some custom control that works well with InArguments). Here's some of the design time code:

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<Window x:Class="WpfApplication4.Window1"
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="WpfApplication4"
  Title="Window1" Height="300" Width="300">
  <Grid>
    <TextBox Height="23" Margin="86,0,72,106" Name="textBox1" VerticalAlignment="Bottom" Style="{StaticResource BigHonkingDigitOnlyTextBox}" />
  </Grid>

  <Window.Resources>
    <Style x:Key="BigHonkingDigitOnlyTextBox" TargetType="TextBox">
      <Setter Property="FontSize" Value="36" />
      <!-- honking

Attached property usage error

I am trying to use attached property...

And i get errors ... here is my code

<

Window x:Class 
="WpfApplication4.Window1"


 

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
 

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
 

xmlns:local="WpfApplication4" 
 

Title="Window1" Height="300" Width="300"> 
 

<Grid 
>


 

<TextBox Height="23" Margin="86,0,72,106" Name="textBox1" VerticalAlignment="Bottom" Style="{StaticResource BigHonkingDigitOnlyTextBox 
}" />


 

</Grid 
>


 

<Window.Resources 
>


 

<Style x:Key="BigHonkingDigitOnlyTextBox" TargetType 
="TextBox">


 

<Setter Property="FontSize" Value 
="36" />


 

<!-- big -->


 

<Setter Property="local:InputBehaviour.HonkOnKeyPress" Value 
="True" />


 

<!-- honking -->


 

<Setter Property="local:InputBehaviour.IsDigitOnly" Value 
="True" />


 

<!-- digit-only -->


 

</Style 
>


 

</Window.Resources 
>


 

 

</

Window>

 

 

 

 

using

 

System;

using

 

System.Collections.Generic;

using

 

System.Linq;

using

 

System.Text;

using

 

System.Windows;

using

 

System.Windo

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