Develop Reference

WPF: Clickable button in ItemTemplate of a ComboBoxItem with IsEnabled=false

Trying to set up a WPF ComboBox;
some of its items should not be selectable, so I'm binding IsEnabled to some property of the underlying item.
At the same time, I need to define an ItemTemplate that contains e.g. a Button.
This button needs to be clickable, even if the item is not selectable (worth nothing a click on the button should not select the item as such of course; it will trigger a command performing some background actions, which will eventually make the underlying item selectable)
However, when ComboBoxItem.IsEnabled = false, it seems even the button automatically gets disabled.
Brief example:
<ComboBox ItemsSource="{Binding Items}">
<ComboBox.ItemContainerStyle>
<Style TargetType="{x:Type ComboBoxItem}">
<Setter Property="IsEnabled" Value="{Binding CanSelectItem}"/>
</Style>
</ComboBox.ItemContainerStyle>
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Name}"/>
<!-- This button isn't clickable when ComboBoxItem.IsEnabled = false .. but it should be! -->
<Button Content="Click me" Command="{Binding SomeCmd}"/>
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
Is there any way to circumvent this? E.g., set some items as non-selectable, however define a button in the ItemTemplate that remains clickable regardless?
Thanks

When you remove the ComboBox.ItemContainerStyle you can set the IsEnabled property of each element in the DataTemplate
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Name}"
IsEnabled="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}, Path=DataContext.IsEnabled}"/>
<Button Content="Click me" Command="{Binding SomeCmd}"/>
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
The combobox item will still be enabled but the TextBlock will be disabled.
The binding is just an example. Depends on where your IsEnabled property is. In my example the property is in the viewmodel which is DataContext of your Window.

For future reference, have found another way of doing this, based on this answer:
WPF override IsEnabled from Parent
So basically creating a class derived from button that overrides the default IsEnabled behavior.
Benefit is that this seems to do exactly what I was looking for, but it does change one of WPF's pretty.. default behaviors, so might need to be taken with a bit of care

MVVM Light - Listbox of UserControls, how to know on which ItemIndex a button is clicked

I got a Listbox where each item is a Usercontrol MatchPanel.
That UserControl has a button.
I d like to remove an item when I click on the button of that item.
I used the SelectedItem which is bind to my ViewModel and works well. But sometimes I m able to click on a button of one item without moving the SelectedItem value (the Listbox item dont get focused even if I click on the button of that item...).
Hence I m looking for a way to receive in the command CloseSelectedMatchCommand a parameter which would tell me, for the button I have clicked, at which index of the Listbox it is.
Thanks
Here is my View
<UserControl
DataContext="{Binding ListTradingMatches, Source={StaticResource Locator}}" Height="503.175" Width="409">
<ListBox ItemsSource="{Binding Path=ListMatches}" SelectedItem="{Binding Path=SelectedMatch}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel>
<local:MatchPanel />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Here is my MatchPanel UserControl
<UserControl x:Class="MatchPanel"
<Label Content="Pts"/>
<Button Command="{Binding RelativeSource={RelativeSource FindAncestor,
AncestorType={x:Type ListBox}},
Path=DataContext.CloseSelectedMatchCommand}" CommandParameter="{Binding}">
</Button>
</Grid>

You can set the DataContext of your UserControl to the item in the DataTemplate:
<DataTemplate>
<StackPanel>
<local:MatchPanel DataContext="{Binding}" />
</StackPanel>
</DataTemplate>
Now the DataContext is set to the item from the collection, you can set the CommandParameter to the relevant property from that object...:
<Button Command="{Binding RelativeSource={RelativeSource FindAncestor,
AncestorType={x:Type ListBox}}, Path=DataContext.CloseSelectedMatchCommand}"
CommandParameter="{Binding Id}" />
..., or just the whole object:
<Button Command="{Binding RelativeSource={RelativeSource FindAncestor,
AncestorType={x:Type ListBox}}, Path=DataContext.CloseSelectedMatchCommand}"
CommandParameter="{Binding}" />

Textbox in Datatemplate MVVM

I am having problems binding a textbox to my viewmodel.
<DataTemplate x:Key="ContentDetail" >
<StackPanel Orientation="Horizontal" Height="500"">
<TextBlock TextWrapping="Wrap" Text="{Binding SelectedCall.CUCODE }" />
</StackPanel>
</DataTemplate>
I know the binding is fine as I have it also bound outside the datatemplate
DataContext="{Binding HelpdeskViewModel, Source={StaticResource ServiceLocator}}"
dx:ThemeManager.ThemeName="VS2010" SelectedItem="{Binding SelectedCall,UpdateSourceTrigger=PropertyChanged}">
Any pointers would be gratefully accepted.
Edit:
<dxg:GridControl.DetailDescriptor>
<dxg:TabViewDetailDescriptor>
<dxg:TabViewDetailDescriptor.DetailDescriptors>
<dxg:ContentDetailDescriptor ContentTemplate="{StaticResource ContentDetail}" HeaderContent="More Detail" >
</dxg:ContentDetailDescriptor>
</dxg:TabViewDetailDescriptor.DetailDescriptors>
</dxg:TabViewDetailDescriptor>
</dxg:GridControl.DetailDescriptor>

Items within a Template are bound to the current item in the Template (so your datacontext in this scope isn't your window's viewmodel, but the current item).
I assume SelectedCall is a property on your window's viewmodel and not a property on each bound item, so you can't access that. If it's also a property of each model then simply bind to CUCODE, else if it's a single per window item, you'd have to trace back to the ancestor window & bind to the datacontext of the window instead of the one automatically set for you within the context of the Template.
You're probably looking for something like that
<TextBlock Text="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type Window}}, Path=SelectedCall.CUCODE }}" />

Changing content according to selected option in WPF

I'm interested in creating an app that displays some buttons and changes a viewport according to the selected button. The viewport in my app is a ContentControl and I thought of changing its content whenever a button is clicked. However, I believe there's a better approach, by perhaps injecting the ViewModels of each of the Views I want to present to the ContentControl and styling them using DataTemplates (Since I want to avoid having a grid with many controls and just setting their Visibility property whenever I want to show a particular view). Which of the approaches seems better to you? Do you have a different approach for this?
The view should be something similar to this:
Thanks!

Usually have a ViewModel behind the window which contains:
ObservableCollection<IViewModel> AvailableViewModels
IViewModel SelectedViewModel
ICommand SetCurrentViewModelCommand
I display the AvailableViewModels using an ItemsControl, which has its ItemTemplate set to a Button. The Button.Command is bound to the SetCurrentViewModelCommand, and it passes the current data item from the AvailableViewModels collection in through the CommandParameter
To display the content area, I use a ContentControl with ContentControl.Content bound to SelectedViewModel, and DataTemplates get used to tell WPF how to render each ViewModel.
The end result is my XAML looks something like this:
<Window.Resources>
<DataTemplate DataType="{x:Type local:ViewModelA}">
<local:ViewA />
</DataTemplate>
<DataTemplate DataType="{x:Type local:ViewModelB}">
<local:ViewB />
</DataTemplate>
</Window.Resources>
<DockPanel>
<Border DockPanel.Dock="Left" BorderBrush="Black" BorderThickness="0,0,1,0">
<ItemsControl ItemsSource="{Binding AvailableViewModels}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Button Content="{Binding Name}"
Command="{Binding DataContext.SetCurrentViewModelCommand, RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"
CommandParameter="{Binding }"
Margin="2,5"/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Border>
<ContentControl Content="{Binding SelectedViewModel}" />
</DockPanel>
You can view an example of the full code used for such a setup on my blog

How to access a Checkbox inside Listbox?

I have a listbox and I have set the itemstemplate as shown below.
XAML:
<ListBox ItemsSource="{Binding DataList}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<CheckBox x:Name="CheckBox" HorizontalAlignment="Center" VerticalAlignment="Center" />
<TextBlock x:Name="TextBlock" Text="{Binding Title}" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="10,0,0,10" FontSize="26.667" TextWrapping="Wrap"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
I want to get which all check box has been selected.Is there any way to get checkbox control for each item so that I can check its IsChecked property.
I can think of a way of binding the IsChecked property.But Is there any other way to do it?

Yes. One way to do is to bind the IsChecked property. And if you are using MVVM, probably that's the right way to do it.
Anyways, if you don't want to go the binding way, and assuming you want to iterate over all items of listbox, and prepare a list of checked items, see if this helps:
WPF - Find a Control from DataTemplate in WPF

If you're already binding to the Title property in the item template then it would certainly make sense to bind to IsChecked, too.
If you really need to, you can walk the visual tree by using the VisualTreeHelper to find the CheckBox instances.

Binding the IsChecked property to a boolean property on your object instance contained within DataList would be the simplest and cleanest way. Alternatively, if you want to avoid code behind, then you could write an attached property.

See also How to access a specific item in a Listbox with DataTemplate?

I bet it cannot be simpler than that:
<ListBox SelectionMode="Multiple" >
<ListBox.ItemTemplate>
<DataTemplate>
<CheckBox
IsChecked="{Binding Path=IsSelected, RelativeSource={RelativeSource AncestorType={x:Type ListBoxItem}}}"
Content="{Binding Path=Content, RelativeSource={RelativeSource AncestorType={x:Type ListBoxItem}}}" />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>