I've got a DataGrid with a row that has an image. This image is bound with a trigger to a certain state. When the state changes I want to change the image.
The template itself is set on the HeaderStyle of a DataGridTemplateColumn. This template has some bindings. The first binding Day shows what day it is and the State changes the image with a trigger.
These properties are set in a ViewModel.
Properties:
public class HeaderItem
{
public string Day { get; set; }
public ValidationStatus State { get; set; }
}
this.HeaderItems = new ObservableCollection<HeaderItem>();
for (int i = 1; i < 15; i++)
{
this.HeaderItems.Add(new HeaderItem()
{
Day = i.ToString(),
State = ValidationStatus.Nieuw,
});
}
Datagrid:
<DataGrid x:Name="PersoneelsPrestatiesDataGrid" HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
AutoGenerateColumns="False" SelectionMode="Single" ItemsSource="{Binding CaregiverPerformances}" FrozenColumnCount="1" >
<DataGridTemplateColumn HeaderStyle="{StaticResource headerCenterAlignment}" Header="{Binding HeaderItems[1]}" Width="50">
<DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<TextBox Text="{ Binding Performances[1].Duration,Converter={StaticResource timeSpanConverter},Mode=TwoWay}"/>
</DataTemplate>
</DataGridTemplateColumn.CellEditingTemplate>
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBlock TextAlignment="Center" Text="{ Binding Performances[1].Duration,Converter={StaticResource timeSpanConverter}}"/>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid>
Datagrid HeaderStyleTemplate:
<Style x:Key="headerCenterAlignment" TargetType="{x:Type DataGridColumnHeader}">
<Setter Property="HorizontalContentAlignment" Value="Center"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type DataGridColumnHeader}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition />
</Grid.RowDefinitions>
<TextBlock Grid.Row="0" Text="{Binding Day}" />
<Image x:Name="imageValidation" Grid.Row="1" Width="16" Height="16" Source="{StaticResource imgBevestigd}" />
</Grid>
<ControlTemplate.Triggers>
<MultiDataTrigger >
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding State}" Value="Nieuw"/>
</MultiDataTrigger.Conditions>
<Setter TargetName="imageValidation" Property="Source" Value="{StaticResource imgGeenStatus}"/>
</MultiDataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Now when I startup the project the images doesn't show and I get this error:
System.Windows.Data Error: 2 : Cannot find governing FrameworkElement or FrameworkContentElement for target element. BindingExpression:Path=HeaderItems[0]; DataItem=null; target element is 'DataGridTemplateColumn' (HashCode=26950454); target property is 'Header' (type 'Object')
Why is this error showing?
Sadly any DataGridColumn hosted under DataGrid.Columns is not part of Visual tree and therefore not connected to the data context of the datagrid. So bindings do not work with their properties such as Visibility or Header etc (although these properties are valid dependency properties!).
Now you may wonder how is that possible? Isn't their Binding property supposed to be bound to the data context? Well it simply is a hack. The binding does not really work. It is actually the datagrid cells that copy / clone this binding object and use it for displaying their own contents!
So now back to solving your issue, I assume that HeaderItems is a property of the object that is set as the DataContext of your parent View. We can connect the DataContext of the view to any DataGridColumn via something we call a ProxyElement.
The example below illustrates how to connect a logical child such as ContextMenu or DataGridColumn to the parent View's DataContext
<Window x:Class="WpfApplicationMultiThreading.Window5"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vb="http://schemas.microsoft.com/wpf/2008/toolkit"
Title="Window5" Height="300" Width="300" >
<Grid x:Name="MyGrid">
<Grid.Resources>
<FrameworkElement x:Key="ProxyElement" DataContext="{Binding}"/>
</Grid.Resources>
<Grid.DataContext>
<TextBlock Text="Text Column Header" Tag="Tag Columne Header"/>
</Grid.DataContext>
<ContentControl Visibility="Collapsed"
Content="{StaticResource ProxyElement}"/>
<vb:DataGrid AutoGenerateColumns="False" x:Name="MyDataGrid">
<vb:DataGrid.ItemsSource>
<x:Array Type="{x:Type TextBlock}">
<TextBlock Text="1" Tag="1.1"/>
<TextBlock Text="2" Tag="1.2"/>
<TextBlock Text="3" Tag="2.1"/>
<TextBlock Text="4" Tag="2.2"/>
</x:Array>
</vb:DataGrid.ItemsSource>
<vb:DataGrid.Columns>
<vb:DataGridTextColumn
Header="{Binding DataContext.Text,
Source={StaticResource ProxyElement}}"
Binding="{Binding Text}"/>
<vb:DataGridTextColumn
Header="{Binding DataContext.Tag,
Source={StaticResource ProxyElement}}"
Binding="{Binding Tag}"/>
</vb:DataGrid.Columns>
</vb:DataGrid>
</Grid>
</Window>
The view above encountered the same binding error that you have found if I did not have implemented the ProxyElement hack. The ProxyElement is any FrameworkElement that steals the DataContext from the main View and offers it to the logical child such as ContextMenu or DataGridColumn. For that it must be hosted as a Content into an invisible ContentControl which is under the same View.
I hope this guides you in correct direction.
A slightly shorter alternative to using a StaticResource as in the accepted answer is x:Reference:
<StackPanel>
<!--Set the DataContext here if you do not want to inherit the parent one-->
<FrameworkElement x:Name="ProxyElement" Visibility="Collapsed"/>
<DataGrid>
<DataGrid.Columns>
<DataGridTextColumn
Header="{Binding DataContext.Whatever, Source={x:Reference ProxyElement}}"
Binding="{Binding ...}" />
</DataGrid.Columns>
</DataGrid>
</StackPanel>
The main advantage of this is: if you already have an element which is not a DataGrid's ancestor (i.e. not the StackPanel in the example above), you can just give it a name and use it as the x:Reference instead, hence not needing to define any dummy FrameworkElement at all.
If you try referencing an ancestor, you will get a XamlParseException at run-time due to a cyclical dependency.
The way without a proxy is to set bindings in the constructor:
var i = 0;
var converter = new BooleanToVisibilityConverter();
foreach(var column in DataGrid.Columns)
{
BindingOperations.SetBinding(column, DataGridColumn.VisibilityProperty, new Binding($"Columns[{i++}].IsSelected")
{
Source = ViewModel,
Converter = converter,
});
}
The Proxy Element didn't work for me, for a tooltip. For an infragistics DataGrid I did this, you might change it easily to your kind of grid:
<igDP:ImageField Label="_Invited" Name="Invited">
<igDP:Field.Settings>
<igDP:FieldSettings>
<igDP:FieldSettings.CellValuePresenterStyle>
<Style TargetType="{x:Type igDP:CellValuePresenter}">
<Setter Property="ToolTip">
<Setter.Value>
<Label Content="{Binding DataItem.InvitationSent, Converter={StaticResource dateTimeConverter}}"/>
</Setter.Value>
</Setter>
</Style>
</igDP:FieldSettings.CellValuePresenterStyle>
</igDP:FieldSettings>
</igDP:Field.Settings>
</igDP:ImageField>
Related
I am trying to set an element in each DataGrid row by setting another element in the same row.
If IsChecked of the ToggleButton is True, image in the ContentControl will become visible.
I have cannibalised this example to try to get this to work. This example seems similiar too and I hope I am not duplicating anything.
This is the code snippet from my implementation of the DataGrid:
<Grid>
<StackPanel>
<Grid Margin="0" Grid.Column="0" Grid.Row="3">
<DataGrid
ItemsSource="{Binding Path=. , Mode=OneWay, NotifyOnSourceUpdated=True, UpdateSourceTrigger=PropertyChanged}"
AutoGenerateColumns="False"
Height="Auto"
HorizontalAlignment="Left"
VerticalAlignment="Top"
ScrollViewer.CanContentScroll="True"
ScrollViewer.VerticalScrollBarVisibility="Visible"
x:Name="Filter_grid"
Grid.Row="1">
<DataGrid.Columns >
<DataGridTextColumn Header="CAN ID" Binding="{Binding Information.CAN_ID}" Width="50" />
<DataGridTextColumn Header="Messagen Name" Binding="{Binding Information.CAN_ID_description}" Width="300" />
<DataGridTextColumn Binding="{Binding Information.Status}" Width="50" />
<DataGridTemplateColumn Header = "Filter ON" Width="SizeToCells" IsReadOnly="True">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<ContentControl Content="{Binding Information.Tick}">
<ContentControl.Style>
<Style TargetType = "ContentControl" >
<Setter Property="Visibility" Value="Hidden"/>
<Style.Triggers>
<DataTrigger Binding = "{Binding Path=IsChecked, ElementName=Filter_on}" Value="True">
<Setter Property = "Visibility" Value="Visible"/>
</DataTrigger>
</Style.Triggers>
</Style>
</ContentControl.Style>
</ContentControl>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
<DataGridTemplateColumn x:Name="F_column" Header ="Select">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<ToggleButton x:Name="Filter_on" Content="Switch" />
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>
</DataGrid>
</Grid>
</StackPanel>
</Grid>
I am unable to get the ElementName to find the ToggleBox and get Cannot find source for binding with reference 'ElementName=Filter_on'.
I have tried doing similiar with
<DataTrigger Binding="{Binding RelativeSource={RelativeSource AncestorType={x:Type DataGridTemplateColumn}}, Path=F_column.Filter_on}" Value="True">, or using x:Reference which throws me an exception I can't decipher.
First things first: you should never do this. XAML is very flexible and allows you to do some terribly clever things, but just because you can doesn't mean you should. The correct solution in this case is to create a view model for each row element with a boolean property that both the button and your data trigger can bind to. Apart from being more flexible it's also much easier to test, debug and log etc.
That said, what you are asking is technically possible. DataGrids are actually quite complex due to various optimizations they employ etc, so you still need to use an intermediate property, but since you don't want to use a view model you'll have to use the Tag property in the button's DataGridCell instead (which can be used for arbitrary user data):
Bind the button's IsChecked property to do a one-way-to-source binding to it's parent DataGridCell's Tag property.
Bind the DataTrigger to find the parent DataGridCellsPanel, and then bind directly to the appropriate child's Tag property i.e. Children[1].Tag.
Put it together and you get this:
<DataGrid ItemsSource="{Binding Items}" AutoGenerateColumns="False">
<DataGrid.Columns>
<DataGridTemplateColumn Header = "Filter ON" Width="SizeToCells" IsReadOnly="True">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<ContentControl>
<ContentControl.Style>
<Style TargetType = "ContentControl" >
<Setter Property="Visibility" Value="Hidden"/>
<Style.Triggers>
<DataTrigger Binding = "{Binding Path=Children[1].Tag, RelativeSource={RelativeSource AncestorType={x:Type DataGridCellsPanel}}}" Value="True">
<Setter Property = "Visibility" Value="Visible"/>
</DataTrigger>
</Style.Triggers>
</Style>
</ContentControl.Style>
<TextBlock Text="Content goes here" />
</ContentControl>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
<DataGridTemplateColumn x:Name="F_column" Header ="Select">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<ToggleButton x:Name="Filter_on" Content="Switch" IsChecked="{Binding Path=Tag, RelativeSource={RelativeSource AncestorType=DataGridCell}, Mode=OneWayToSource}" />
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>
</DataGrid>
But seriously...just use a view model.
I have the following user control with a custom dependency property
ThumbnailListView UserControl
<ListView
ItemsSource="{Binding}"
BorderThickness="0,0,0,0"
HorizontalAlignment="Center"
Background="White"
SelectionChanged="ListView_SelectionChanged"
AllowDrop="True">
<i:Interaction.Behaviors>
<behaviors:DragDropBehavior OnDragDrop="{Binding Path=ItemDragDrop}"></behaviors:DragDropBehavior>
</i:Interaction.Behaviors>
<ListView.ItemContainerStyle>
<Style TargetType="{x:Type ListBoxItem}">
<Style.Triggers>
<DataTrigger Binding="{Binding RelativeSource={RelativeSource Self}, Converter={StaticResource IsLastListItem}}" Value="False">
<Setter Property="Margin" Value="0,0,0,20"></Setter>
</DataTrigger>
</Style.Triggers>
<Setter Property="Background" Value="Gray"></Setter>
<Setter Property="IsSelected" Value="{Binding Path=IsSelected, Mode=TwoWay}"></Setter>
</Style>
</ListView.ItemContainerStyle>
<ListView.ItemTemplate>
<DataTemplate>
<Image Source="{Binding Thumbnail, Converter={StaticResource ImageConverter}}"></Image>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
Dependency Property ItemDragDrop of ThumbnailListView
public static ICommand GetItemDragDrop(DependencyObject obj)
{
return (ICommand)obj.GetValue(ItemDragDropProperty);
}
public static void SetItemDragDrop(DependencyObject obj, ICommand value)
{
obj.SetValue(ItemDragDropProperty, value);
}
public static DependencyProperty ItemDragDropProperty = DependencyProperty.RegisterAttached("ItemDragDrop",
typeof(ICommand), typeof(ThumbnailListView));
public ICommand ItemDragDrop
{
get
{
return (ICommand)GetValue(ItemDragDropProperty);
}
set
{
SetValue(ItemDragDropProperty, value);
}
}
NewScansView UserControl
<DockPanel Dock="Top">
<ListView ItemsSource="{Binding Scans}" Width="500">
<ListView.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Caption}" Margin="5,0,0,0"></TextBlock>
</DataTemplate>
</ListView.ItemTemplate>
<ListView.ItemContainerStyle>
<Style TargetType="{x:Type ListViewItem}">
<Setter Property="IsSelected" Value="{Binding Path=IsSelected, Mode=TwoWay}"/>
</Style>
</ListView.ItemContainerStyle>
</ListView>
<Views:ThumbnailListView DataContext="{Binding SelectedItem.Pages}" ItemDragDrop="{Binding SelectedItem.DragDropCommand}" VerticalAlignment="Stretch" Width="200" />
<Views:PageListView DataContext="{Binding SelectedItem.Pages}" VerticalAlignment="Stretch" />
</DockPanel>
The NewScansView xaml contains a ThumbnailListView control and has bound the dependency property ItemDragDrop of the ThumbnailListView to a command in the class of SelectedItem.
Inside the ThumbnailListView user control I have a behavior DragDropBehavior which has a dependency property OnDragDrop.
I am trying to bind OnDragDrop to ItemDragDrop so that when a drag drop operation completes the command in the SelectedItem class is executed.
The problem is that it doesn't seem to be able to find either the ItemDragDrop property on the ThumbnailListView or the DragDropCommand of the selected item class.
I'm wondering what i'm doing wrong and how I can set it up?
ThumbnailListView.DataContext is set to SelectedItem.Pages, and I highly doubt that SelectedItem.Pages has a property called SelectedItem.DragDropCommand.
Change the Source of your ItemDragDrop binding to specify it uses something other than the ThumnailListView.DataContext for the source of that binding.
<DockPanel x:Name="MyDockPanel" Dock="Top">
...
<Views:ThumbnailListView DataContext="{Binding SelectedItem.Pages}"
ItemDragDrop="{Binding SelectedItem.DragDropCommand, ElementName=MyDockPanel}" ... />
...
</DockPanel>
You probably also have to do the same for your behavior binding - change the source of it so it points to the ThumbnailListView instead of to the ThumbnailListView.DataContext
<i:Interaction.Behaviors>
<behaviors:DragDropBehavior OnDragDrop="{Binding Path=ItemDragDrop, RelativeSource={RelativeSource AncestorType={x:Type local:ThumbnailListView}}}" />
</i:Interaction.Behaviors>
Or better yet, either make a DependencyProperty for Pages so you don't rely on a specific DataContext object type
<Views:ThumbnailListView PagesDependencyProperty="{Binding SelectedItem.Pages}" ItemDragDrop="{Binding SelectedItem.DragDropCommand}" .. />
Or edit your control so it assumes a specific type is being used for the DataContext, and use an implicit DataTemplate to always draw that type of object using this control (far more common for me) :
<ListView ItemsSource="{Binding Pages}" ...>
<i:Interaction.Behaviors>
<behaviors:DragDropBehavior OnDragDrop="{Binding DragDropCommand}" />
</i:Interaction.Behaviors>
...
</ListView>
Implicit DataTemplate:
<DataTemplate DataType="{x:Type local:WhateverSelectedItemDataTypeIs}}">
<!-- DataContext will automatically set to WhateverSelectedItemDataTypeIs -->
<Views:ThumbnailListView />
</DataTemplate>
I try to group some data in wpf datagrid .. it works fine, except the HEADER OF TEMPLATE DOESN'T DISPLAY any thing. It should display teacher name by TEACHER property. I use SQtOLinq as the underlayer data source.
what did I miss in my code?
XAML code:
<DataGrid AutoGenerateColumns="False" Height="311" Style="{StaticResource DashboardGridStyle}" HorizontalAlignment="Left" Name="TeacherDetailsDG" VerticalAlignment="Top" Width="322" ItemsSource="{Binding}" Margin="178,0,0,0" SelectionChanged="TeacherDetailsDG_SelectionChanged" RowBackground="#FF00E700" SelectionUnit="FullRow" BorderBrush="#FF00E400" AlternatingRowBackground="#FFC4B5B5">
<DataGrid.GroupStyle>
<GroupStyle>
<GroupStyle.HeaderTemplate>
<DataTemplate>
<StackPanel >
<TextBlock Text="{Binding Path=Teacher,Mode=TwoWay}" Foreground="Blue"/>
</StackPanel>
</DataTemplate>
</GroupStyle.HeaderTemplate>
<GroupStyle.ContainerStyle>
<Style TargetType="{x:Type GroupItem}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type GroupItem}">
<Expander x:Name="exp">
<Expander.Header>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Path=Teacher,Mode=TwoWay}" />
</StackPanel>
</Expander.Header>
<Expander.Content>
<ItemsPresenter Visibility="{Binding ElementName=exp, Path=IsExpanded}" />
</Expander.Content>
</Expander>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</GroupStyle.ContainerStyle>
</GroupStyle>
</DataGrid.GroupStyle>
<DataGrid.Columns>
<DataGridTextColumn Binding="{Binding Path=TeacherID}" Visibility="Hidden">
</DataGridTextColumn>
<DataGridTextColumn Binding="{Binding Path=Teacher}"/>
<!--Grades column-->
<DataGridComboBoxColumn x:Name="GradesCombo" ItemsSource="{Binding}" DisplayMemberPath="Grade" SelectedValuePath="ID" SelectedValueBinding="{Binding Path=GradeID}"></DataGridComboBoxColumn>
<!--Subjects column-->
<DataGridComboBoxColumn x:Name="SubjectsCombo" ItemsSource="{Binding}" DisplayMemberPath="Subject" SelectedValuePath="ID" SelectedValueBinding="{Binding Path=SubjectID}"></DataGridComboBoxColumn>
</DataGrid.Columns>
</DataGrid>
Datagrid Binding code:
public MainWindow()
{
InitializeComponent();
GradesCombo.ItemsSource = SchoolDC.GradesTables;
SubjectsCombo.ItemsSource = SchoolDC.SubjectsTables;
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
try
{
CollectionView view = (CollectionView)CollectionViewSource.GetDefaultView((SchoolDC.TeachersDetailsSP().ToList<object>()));
view.GroupDescriptions.Add(new PropertyGroupDescription("Teacher"));
TeacherDetailsDG.ItemsSource = view;
}
catch (Exception)
{
throw;
}
}
This is the result:
GroupItem.Name gets the value of the property you grouped by .
<DataTemplate>
<TextBlock Text="{Binding Path=Name}" Foreground="Blue"/>
</DataTemplate>
If you are using ReSharper, (and you most definitely are, aren't you?) the problem with the accepted answer is that the reference to Name will be flagged with "Cannot resolve property 'Name' in data context of type 'Xyz'" where Xyz is the type of the enclosing data context, most probably the ViewModel of your screen.
(Or, your enclosing data context might also have a property called 'Name', in which case you will be oblivious to the discrepancy.)
To remedy this problem, change <DataTemplate> to <DataTemplate DataType="GroupItem"> to let WPF (and ReSharper) know what is the actual type of the data context that the DataTemplate is going to be applied to.
Then, the Name property will not be flagged anymore, and as a matter of fact, if you choose "Go to definition" on the property you will be taken to the Name property of UIElement, from which GroupItem inherits it. (Assuming that you are, of course, using ReSharper, instead of just plain woefully inadequate Visual Studio, right?)
I use c# .NET 4.5 and WPF RadControls from Telerik.
On my MainWindow I have a RadTabControl and in my code behind I bind my MainViewModel like this:
this.DataContext = new MainViewmodel();
The ItemSource of the RadTabControl is bound in XAML:
<telerik:RadTabControl ... ItemsSourc={Binding Tabs} .. />
I also use a ContentSelector to load different Contents to my Tabs. These Contents are UserControls. On one UserControl I use a RadGRidView with it's own ItemsSource that I bind in the code behind:
TestGridView.ItemsSource = Tasks.GetTasks();
The RadGridView Columns bound to it's own style:
<telerik:RadGridView.Columns>
<telerik:GridViewDataColumn DataMemberBinding="{Binding ID}" Width="*" CellStyle="{StaticResource CellStyle}" />
</telerik:RadGridView.Columns>
<Style x:Key="CellStyle" TargetType="{x:Type telerik:GridViewCell}">
<Setter Property="BorderThickness" Value="0" />
<Setter Property="BorderBrush" Value="{x:Null}" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate>
<Border BorderBrush="#f2f2f2" BorderThickness="0,0,0,2" Padding="0,5,0,5">
<StackPanel Orientation="Horizontal">
<StackPanel Orientation="Vertical" Margin="10,0,0,0" VerticalAlignment="Top">
<TextBlock Text="{Binding Titel}" />
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Start}" Foreground="#9fa2ae"/>
<TextBlock Text=" XXX - XXX " />
<TextBlock Text="{Binding Startzeit}" Foreground="#9fa2ae" />
<telerik:RadButton Height="30" Content="Right Button" Command="{Binding AddTabCommand}" CommandParameter="Tab9999"/>
</StackPanel>
</StackPanel>
</StackPanel>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
The Problem is that the RadButton does not fire the DelegateCommand of my MainViewModel. I have also the same Button in the UserControl out of the RadGridView, this works fine.
Please can somebody tell me how I can fix this problem of my RadButton in the RadGridView?
Thanks a lot
Best Regards
RR
PS: I have a simple project, but can't attach it
The reason why this is happening is that the binding on your RadButton is trying to find the AddTabCommand on the DataContext of the button, not the parent Window.
To fix this, I would advise setting the style inside the Window's resources, and instead of using this:
Command="{Binding AddTabCommand}"
Give the Window a name, and use this:
Command="{Binding ElementName=windowName, Path=DataContext.AddTabCommand}"
Agree with what Mike said its not finding AddTabCommand in your DataContext(ViewModel).
You can try with specifying whole path of the command :
Command="{Binding ElementName=windowName, Path=NameSapce_Name.ViewModelName.AddTabCommand}".
.Net 3.5
I know that the columns doesn't inherit the datacontext and by reading other posts i thought this would work:
Visibility="{Binding RelativeSource={x:Static RelativeSource.Self},
Path=(FrameworkElement.DataContext).IsColumnNameVisible,
Converter={StaticResource boolToVisConverter}}"
However of course it doesn't..
The output window does not complain, it seems that the resource i found but the viewmodel property is newer called.
This is the entire DG :
<tk:DataGrid
VirtualizingStackPanel.IsVirtualizing="False"
Grid.Column="0"
AlternationCount="2"
AreRowDetailsFrozen="True"
AutoGenerateColumns="False"
Background="Transparent"
BorderThickness="0"
CanUserAddRows="False"
CanUserReorderColumns="True"
CanUserResizeRows="False"
GridLinesVisibility="None"
ItemsSource="{Binding Employees}"
SelectionMode="Single"
ColumnHeaderStyle="{StaticResource columnHeaderStyle}"
RowHeaderStyle="{StaticResource rowHeaderStyle}"
CellStyle="{StaticResource cellStyle}"
RowStyle="{StaticResource rowStyle}"
ContextMenu="{StaticResource columnHeaderContextMenu}">
<tk:DataGrid.Resources>
<ContextMenu x:Key="columnHeaderContextMenu" ItemsSource="{Binding ColumnHeaderContextMenuItems}" />
<Style TargetType="{x:Type ScrollBar}">
<Setter Property="Background" Value="Transparent"/>
</Style>
<Style TargetType="{x:Type tk:DataGridColumnHeader}">
<Setter Property="Background" Value="Transparent"/>
</Style>
</tk:DataGrid.Resources>
<tk:DataGrid.Triggers>
<EventTrigger RoutedEvent="tk:DataGridRow.MouseDoubleClick">
<EventTrigger.Actions>
<BeginStoryboard Storyboard="{StaticResource showDetailGrid}"/>
</EventTrigger.Actions>
</EventTrigger>
</tk:DataGrid.Triggers>
<tk:DataGrid.Columns>
<tk:DataGridTextColumn IsReadOnly="True" Header="test" Binding="{Binding Name, Mode=OneWay}" Visibility="{Binding RelativeSource={x:Static RelativeSource.Self}, Path=(FrameworkElement.DataContext).IsColumnNameVisible, Converter={StaticResource boolToVisConverter}}" />
</tk:DataGrid.Columns>
</tk:DataGrid>
I have read pretty much every single solution to this problem and nothing works..
DataGridColumns are not part of visual tree so they are not connected to the data context of the DataGrid.
For them to connect together use proxy element approach like this...
Add a proxy FrameworkElement in your ancestor panel's Resources.
Host it into an invisible ContentControl bound to its Content.
Use this ProxyElement as StaticResource for data context source in your visibility binding.
<StackPanel>
<StackPanel.Resources>
<local:BooleanToVisibilityConverter
x:Key="BooleanToVisibilityConverter" />
<FrameworkElement x:Key="ProxyElement"
DataContext="{Binding}"/>
</StackPanel.Resources>
<ContentControl Visibility="Collapsed"
Content="{StaticResource ProxyElement}"/>
<DataGrid AutoGenerateColumns="False">
<DataGrid.Columns>
<DataGridTextColumn
Visibility="{Binding DataContext.IsTextColumnVisibile,
Source={StaticResource ProxyElement},
Converter={StaticResource
BooleanToVisibilityConverter}}"
Binding="{Binding Text}"/>
</DataGrid.Columns>
</DataGrid>
</StackPanel>
Apart from DataGridColumn, the above approach also works great to connect DataContext to Popups and ContextMenus (i.e. any element that is not connected to the visual tree).
Silverlight Users
Sadly setting contents of content controls with any framework elements is not allowed in silverlight. So the workaround would be (this is just a guidance code for silverlight) ...
Change the framework element resource to something lightweight like a Textblock. (Silverlight does not allow specifying static resource of FrameworkElement type.)
<StackPanel.Resources>
<TextBlock x:Key="MyTextBlock" />
Write an attached property to hold text block against the content control.
<ContentControl Visibility="Collapsed"
local:MyAttachedBehavior.ProxyElement="{StaticResource MyTextBlock}" />
In the attached dependency property changed event handler, set the bind the data context of the content control to the text block's.
private static void OnProxyElementPropertyChanged(
DependencyObject depObj, DependencyPropertyChangedEventArgs e)
{
if (depObj is ContentControl && e.NewValue is TextBlock)
{
var binding = new Binding("DataContext");
binding.Source = depObj;
binding.Mode = OneWay;
BindingOperations.SetBinding(
(TextBlock)e.NewValue, TextBlock.DataContextProperty, binding);
}
}
So this way the textblock may not be connected to the visual tree but will probably be aware of the data context changes.