Develop Reference

WPF, TabItem Images

Have TabControl, which binding to array , need add to TabItem different icons/image.
haml code:
<Grid>
<TabControl VirtualizingPanel.VirtualizationMode="Recycling" Style="{StaticResource TabControl}"
ItemsSource="{Binding Workspaces}" SelectedIndex="{Binding CurrentPage,UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}">
<TabControl.ItemContainerStyle>
<Style BasedOn="{StaticResource TabItem}" TargetType="{x:Type TabItem}">
<Setter Property="Header" Value="{Binding HeaderText}"/>
</Style>
</TabControl.ItemContainerStyle>
<TabControl.ContentTemplate>
<DataTemplate>
<ContentPresenter Content="{Binding Content}" />
</DataTemplate>
</TabControl.ContentTemplate>
</TabControl>
</Grid>

You should set a ItemTemplateSelector at your TabControl:
<TabControl VirtualizingPanel.VirtualizationMode="Recycling" Style="{StaticResource TabControl}"
ItemsSource="{Binding Workspaces}" SelectedIndex="{Binding CurrentPage,UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}"
ItemTemplateSelector="{StaticResource myItemDataTemplateSelector}" >
Your TemplateSelector should look like this:
public class MyItemDataTemplateSelector : DataTemplateSelector
{
public override DataTemplate SelectTemplate(object item, DependencyObject container)
{
FrameworkElement element = container as FrameworkElement;
if (element != null && item != null && item is MyItem)
{
var myItem = item as MyItem;
var window = Application.Current.MainWindow;
switch (myItem.SpecialFeatures)
{
case SpecialFeatures.None:
return
element.FindResource("Item_None_DataTemplate")
as DataTemplate;
case SpecialFeatures.Color:
return
element.FindResource("Item_Color_DataTemplate")
as DataTemplate;
}
}
return null;
}
}
Reference: https://msdn.microsoft.com/en-us/library/system.windows.controls.itemscontrol.itemtemplateselector(v=vs.110).aspx

How to draw grid lines that scale?

I have a canvas, and I want to give it grid lines as a background, but I want there to be a constant number of grid lines that divide the canvas into equally-sized sections, rather than just have equally-spaced grid-lines. I want this to be preserved when the canvas is resized by the user.
How should I do this?

Here is a solution which is based in two wpf ListView controls behind the canvas(one for rows and second for columns). The content of the columns related ListView control is a rectangle.
Updated version - Managed Grid Lines Control. Here you can manage the number of grid lines and their visibility.
Xaml code - grid lines control:
<UserControl x:Class="CAnvasWithGrid.GridLineControl"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:canvasWithGrid="clr-namespace:CAnvasWithGrid"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300" x:Name="This">
<Grid x:Name="LayoutRoot">
<Grid.Resources>
<Style TargetType="ListView">
<Setter Property="Background" Value="Transparent"/>
</Style>
<Style x:Key="ListViewItemStyle" TargetType="ListViewItem">
<Setter Property="Background" Value="Transparent"/>
</Style>
<DataTemplate x:Key="InnerListviewDataTemplate" DataType="{x:Type canvasWithGrid:CellModel}">
<Rectangle HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
Margin="0" StrokeDashArray="4" Stroke="Black" StrokeThickness="0.5" Fill="Transparent"/>
</DataTemplate>
<DataTemplate x:Key="ListviewDataTemplate" DataType="{x:Type canvasWithGrid:RowModel}">
<ListView ItemsSource="{Binding CellModels}" BorderBrush="#00FFFFFF" BorderThickness="0" Margin="0"
HorizontalContentAlignment="Stretch"
VerticalContentAlignment="Stretch"
VerticalAlignment="Stretch"
HorizontalAlignment="Stretch" ScrollViewer.HorizontalScrollBarVisibility="Hidden" ScrollViewer.VerticalScrollBarVisibility="Hidden">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid Columns="{Binding CellModels, Converter={canvasWithGrid:CollectionLength2NumberConverter}}"></UniformGrid>
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem" BasedOn="{StaticResource ListViewItemStyle}">
<Setter Property="Margin" Value="0"></Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListViewItem">
<ContentPresenter Content="{TemplateBinding Content}" Margin="0"
ContentTemplate="{StaticResource InnerListviewDataTemplate}" />
</ControlTemplate>
</Setter.Value>
</Setter>
<Setter Property="ContentTemplate" Value="{StaticResource InnerListviewDataTemplate}"/>
</Style>
</ListView.ItemContainerStyle>
</ListView>
</DataTemplate>
</Grid.Resources>
<ListView ItemsSource="{Binding ElementName=This, Path=RowModels}" ScrollViewer.HorizontalScrollBarVisibility="Hidden" ScrollViewer.VerticalScrollBarVisibility="Hidden">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid Rows="{Binding ElementName=This, Path=RowModels, Converter={canvasWithGrid:CollectionLength2NumberConverter}}"/>
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem" BasedOn="{StaticResource ListViewItemStyle}">
<Setter Property="Margin" Value="0"></Setter>
<Setter Property="HorizontalAlignment" Value="Stretch"/>
<Setter Property="VerticalAlignment" Value="Stretch"/>
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Setter Property="VerticalContentAlignment" Value="Stretch"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListViewItem">
<ContentPresenter Content="{TemplateBinding Content}" Margin="-1"
ContentTemplate="{StaticResource ListviewDataTemplate}" />
</ControlTemplate>
</Setter.Value>
</Setter>
<Setter Property="ContentTemplate" Value="{StaticResource ListviewDataTemplate}"/>
</Style>
</ListView.ItemContainerStyle>
</ListView>
</Grid>
Grid lines control - code behind
/// <summary>
/// Interaction logic for GridLineControl.xaml
/// </summary>
public partial class GridLineControl : UserControl
{
public GridLineControl()
{
InitializeComponent();
}
public static readonly DependencyProperty NumberOfColumnsProperty = DependencyProperty.Register(
"NumberOfColumns", typeof (int), typeof (GridLineControl), new PropertyMetadata(default(int), NumberOfColumnsChangedCallback));
private static void NumberOfColumnsChangedCallback(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs args)
{
var numberOfRows = (int)dependencyObject.GetValue(NumberOfRowsProperty);
var numberOfColumns = (int)args.NewValue;
if (numberOfColumns == 0 || numberOfRows == 0) return;
var rowModelsCollection = GetRowModelsCollection(numberOfRows, numberOfColumns);
dependencyObject.SetValue(RowModelsProperty, rowModelsCollection);
}
public int NumberOfColumns
{
get { return (int) GetValue(NumberOfColumnsProperty); }
set { SetValue(NumberOfColumnsProperty, value); }
}
public static readonly DependencyProperty NumberOfRowsProperty = DependencyProperty.Register(
"NumberOfRows", typeof (int), typeof (GridLineControl), new PropertyMetadata(default(int), NumberOfRowsChangedCallback));
private static void NumberOfRowsChangedCallback(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs args)
{
var numberOfRows = (int)args.NewValue;
var numberOfColumns = (int)dependencyObject.GetValue(NumberOfColumnsProperty);
if(numberOfColumns == 0 || numberOfRows == 0) return;
var rowModelsCollection = GetRowModelsCollection(numberOfRows, numberOfColumns);
dependencyObject.SetValue(RowModelsProperty, rowModelsCollection);
}
private static ObservableCollection<RowModel> GetRowModelsCollection(int numberOfRows, int numberOfColumns)
{
var rowModelsCollection = new ObservableCollection<RowModel>();
for (var i = 0; i < numberOfRows; i++)
{
rowModelsCollection.Add(new RowModel(numberOfColumns) {Position = (i + 1).ToString()});
}
return rowModelsCollection;
}
public int NumberOfRows
{
get { return (int) GetValue(NumberOfRowsProperty); }
set { SetValue(NumberOfRowsProperty, value); }
}
public static readonly DependencyProperty RowModelsProperty = DependencyProperty.Register("RowModels",
typeof(ObservableCollection<RowModel>), typeof(GridLineControl),
new PropertyMetadata(default(ObservableCollection<RowModel>)));
public ObservableCollection<RowModel> RowModels
{
get { return (ObservableCollection<RowModel>)GetValue(RowModelsProperty); }
private set { SetValue(RowModelsProperty, value); }
}
}
Models:
public class RowModel:BaseGridMember
{
public RowModel(int numberOfCellsInRow)
{
CellModels = new ObservableCollection<CellModel>();
for (int i = 0; i < numberOfCellsInRow; i++)
{
CellModels.Add(new CellModel{Position = (i+1).ToString()});
}
}
public ObservableCollection<CellModel> CellModels { get; set; }
}
public class CellModel:BaseGridMember
{
}
public class BaseGridMember:BaseObservableObject
{
private string _position;
public string Position
{
get { return _position; }
set
{
_position = value;
OnPropertyChanged();
}
}
}
Main window xaml code - as you can see here is a ImageContol instead of Canvas but you can replace it:
<Window x:Class="CAnvasWithGrid.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:canvasWithGrid="clr-namespace:CAnvasWithGrid"
Title="MainWindow" Height="525" Width="525" x:Name="This">
<Grid Tag="{Binding ElementName=This}">
<Grid.Resources>
<BooleanToVisibilityConverter x:Key="Bool2VisConvKey" />
</Grid.Resources>
<Grid.ContextMenu>
<ContextMenu DataContext="{Binding Path=PlacementTarget.Tag, RelativeSource={RelativeSource Self}}">
<MenuItem Header="Show Grid Lines" Command="{Binding ShowGridLinesCommand}"/>
</ContextMenu>
</Grid.ContextMenu>
<Image Source="Resources/Koala.jpg" Stretch="Uniform" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" MouseDown="UIElement_OnMouseDown"/>
<canvasWithGrid:GridLineControl NumberOfRows="50" NumberOfColumns="50"
IsHitTestVisible="False" Visibility="{Binding ElementName=This, Path=AreGridLineVisible, Converter={StaticResource Bool2VisConvKey}, UpdateSourceTrigger=PropertyChanged}"/>
</Grid>
Main window code behind:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
ShowGridLinesCommand = new RelayCommand(ShowGridLineManageCommand);
AreGridLineVisible = true;
}
private void ShowGridLineManageCommand()
{
AreGridLineVisible = !AreGridLineVisible;
}
public static readonly DependencyProperty AreGridLineVisibleProperty = DependencyProperty.Register(
"AreGridLineVisible", typeof (bool), typeof (MainWindow), new PropertyMetadata(default(bool)));
public bool AreGridLineVisible
{
get { return (bool) GetValue(AreGridLineVisibleProperty); }
set { SetValue(AreGridLineVisibleProperty, value); }
}
public static readonly DependencyProperty ShowGridLinesCommandProperty = DependencyProperty.Register(
"ShowGridLinesCommand", typeof (ICommand), typeof (MainWindow), new PropertyMetadata(default(ICommand)));
public ICommand ShowGridLinesCommand
{
get { return (ICommand) GetValue(ShowGridLinesCommandProperty); }
set { SetValue(ShowGridLinesCommandProperty, value); }
}
private void UIElement_OnMouseDown(object sender, MouseButtonEventArgs e)
{
}
}
How it looks like:

Sounds like a candidate for a custom control with custom drawing. You don't really want to use multiple FrameworkElements like "Line" if you are expecting many grid-lines for performance reasons.
So you'd create a customControl GridLinesControl and overwrite the OnRender method. You can get the actual width and height of the component using the properties ActualWidth and ActualHeight, divide by the number of grid lines you want and draw lines using drawingContext.DrawLine.
The easiest way would be to add the GridLinesControl you've made underneath the canvas, taking up the same space (so it has the right ActualWidth and ActualHeight) like this:
<Grid>
<myControls:GridLinesControl/>
<Canvas ... />
</Grid>
So it's always underneath.

How do you hide a ListView Item placeholder when it's DataTemplate child is collapsed?

When the visibility of a CarViewControl is set to collapsed, it still shows a placeholder where it used to be (see screenshot below).
Is there any way to completely hide a ListViewItem when it is Collapsed?
XAML Code
<ScrollViewer>
<ListView ItemsSource="{Binding CarVM.UserCars}" ShowsScrollingPlaceholders="False">
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
</Style>
</ListView.ItemContainerStyle>
<ListView.ItemTemplate>
<DataTemplate>
<ctrl:CarViewControl Car="{Binding}" Visibility="{Binding HideCar, Converter={ThemeResource InverseVisConverter}}" />
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</ScrollViewer>
In the image above, there are three CarViewControls which are collapsed, followed by one which is not. One is highlighted. I want them to be completely invisible when the content is collapsed.
What I've tried:
Setting height of the DataTemplate control to 0 (just to see if it hides the placeholder which had no effect
Setting ShowsScrollingPlaceholders to False based on this documentation: MSDN ListView Placeholders
Reason For Collapse Requirement
Within each CarViewControl, a WebView exists which includes a security token (which maintains that the WebView is logged into a specific web site). If you try to pass the WebView by reference, due to what I can only assume are security measures, you lose that security token and must re-login to the site. That is why adding/removing the control from the ObservableCollection will not work in my case.

I would say your design is flawed, but I can't fix that; so I'll provide a "workaround."
The issue is that your DataTemplate is collapsing, which is great, but clearly the container it is in doesn't collapse. This won't happen inherently because the parent won't inherit from a child. First realization is every item is wrapped in a ListViewItem and you can observe that from setting your ItemContainerStyle. This leaves you with two solutions (workarounds). You can either set up some triggers on your ListViewItem or you can do something easier like I did--and if you don't mind the UI affects.
My full working application is below. The main point is that you have to edit the layout/behavior of the ListViewItem. In my example, the default values aren't BorderThickeness and Padding isn't "0, 0, 0, 0"... Setting those to 0 will get hide your items completely.
MainWindow.xaml
<Window x:Class="CollapsingListViewItemContainers.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:CollapsingListViewItemContainers"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<BooleanToVisibilityConverter x:Key="BoolToVisConverter"></BooleanToVisibilityConverter>
</Window.Resources>
<Grid>
<StackPanel>
<Button Content="Disappear Car 3" Click="Button_Click" />
<ListView ItemsSource="{Binding Cars}">
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Setter Property="MinHeight" Value="0" />
<Setter Property="Padding" Value="0 0 0 0" />
</Style>
</ListView.ItemContainerStyle>
<ListView.ItemTemplate>
<DataTemplate DataType="{x:Type local:Car}">
<Grid Visibility="{Binding IsVisible, Converter={StaticResource BoolToVisConverter}}">
<StackPanel>
<TextBlock Text="{Binding Name}" />
<TextBlock Text="{Binding Title}" />
<TextBlock Text="{Binding Id}" />
</StackPanel>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackPanel>
</Grid>
</Window>
MainWindow.xaml.cs
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows;
namespace CollapsingListViewItemContainers
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public ObservableCollection<Car> _cars = new ObservableCollection<Car>
{
new Car("Not yours", "Mine", 1),
new Car("Not mine", "Yours", 2),
new Car("Not ours", "His", 3),
new Car("Not ours", "Hers", 4),
};
public ObservableCollection<Car> Cars
{
get
{
return _cars;
}
}
public MainWindow()
{
InitializeComponent();
DataContext = this;
}
private void Button_Click(object sender, RoutedEventArgs e)
{
Cars[2].IsVisible = !Cars[2].IsVisible;
}
}
public class Car : INotifyPropertyChanged
{
private bool _isVisible;
public bool IsVisible
{
get
{
return _isVisible;
}
set
{
_isVisible = value;
NotifyPropertyChanged("IsVisible");
}
}
public string Name
{
get; set;
}
public string Title
{
get; set;
}
public int Id
{
get; set;
}
public Car(string name, string title, int id)
{
Name = name;
Title = title;
Id = id;
IsVisible = true;
}
public event PropertyChangedEventHandler PropertyChanged;
public void NotifyPropertyChanged(string propertyName)
{
if(PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}
Edit
Let's be honest, the above was a pretty cheap solution and I wasn't satisfied with it after thinking about it for another 3 minutes. The reason I'm dissatisfied is because you can still select the item if you have access to a keyboard. In the example above, click the first item, "hide" the item(s), then use your mouse and the ListView.SelectedItem will still change.
So below is a quick solution (workaround :D ) to actually remove the item from the list and preventing them from getting focus. Replace the ListView.ItemContainerStyle with this one and change the ActualHeight trigger value to match the values you're seeing. This will change based on OS themes I believe--I'll leave it up to you to test. Lastly, remember the ListViewItem.DataContext is going to be that of an item in the ItemsSource. This means the DataTrigger bound to IsVisible is bound to the Car.IsVisible property.
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Style.Triggers>
<Trigger Property="ActualHeight" Value="4">
<Setter Property="Visibility" Value="Collapsed" />
</Trigger>
<DataTrigger Binding="{Binding IsVisible}" Value="True">
<Setter Property="Visibility" Value="Visible" />
</DataTrigger>
</Style.Triggers>
</Style>
</ListView.ItemContainerStyle>
Edit 2 (edited before I even posted the first edit.
Screw it, don't bind visibility of your CarViewControl; You don't need to. You solely need to focus on removing the item itself, and once the item is removed, the containing controls will be removed as well (though you should test this yourself and change IsTabStop and IsFocusable if you can still tab to items in CarViewControl). Also, since using an arbitrary number with the ActualHeight binding isn't very safe, just binding straight to the IsVisible property (or HideCar in your case) and triggering visibility of the ListViewItem should be sufficient.
Finally, here is my final XAML:
<Window x:Class="CollapsingListViewItemContainers.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:CollapsingListViewItemContainers"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<BooleanToVisibilityConverter x:Key="BoolToVisConverter"></BooleanToVisibilityConverter>
</Window.Resources>
<Grid>
<StackPanel>
<Button Content="Disappear Car 3" Click="Button_Click" />
<ListView ItemsSource="{Binding Cars}">
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Style.Triggers>
<DataTrigger Binding="{Binding IsVisible}" Value="False">
<Setter Property="Visibility" Value="Collapsed" />
</DataTrigger>
<DataTrigger Binding="{Binding IsVisible}" Value="True">
<Setter Property="Visibility" Value="Visible" />
</DataTrigger>
</Style.Triggers>
</Style>
</ListView.ItemContainerStyle>
<ListView.ItemTemplate>
<DataTemplate DataType="{x:Type local:Car}">
<Grid>
<StackPanel>
<TextBlock Text="{Binding Name}" />
<TextBlock Text="{Binding Title}" />
<TextBlock Text="{Binding Id}" />
</StackPanel>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackPanel>
</Grid>
</Window>

Instead of attempting to hide item via the UI, I would remove the item from the View or Collection that the ItemsSource is bound against. It's a cleaner approach, and the UI never has to be concerned about Visibility of an item.
EDIT 1
When a user selects a specific car from the quick select menu, it shows that car and hides the others.
Makes sense; let's call that view "UserCars", and assume the ItemsSource is bound to UserCars.
How about this: change the ItemsSource to be bound to "SelectedCollection". When you want to show UserCars, point SelectedCollection to the UserCars collection.
To limit the set, you'd simply point SelectedCollection to a new SingleCar that you populate with only UserCars.SelectedItem
XAML:
<ListView ItemsSource="{Binding SelectedCollection}" SelectedItem="{Binding SelectedCar}">
ViewModel:
private Car _selectedCar;
public Car SelectedCar {
get { return _selectedCar; }
set { _selectedCar = value; OnPropertyChanged("SelectedCar"); }
}
private ObservableCollection<Car> _selectedCollection = CarVM.UserCars;
private ObservableCollection<Car> SelectedCollection {
get { return _selectedCollection; }
set { _selectedCollection = value; OnPropertyChanged("SelectedCollection"); }
}
private ObservableCollection<Car> _originalCollectionForReferenceKeepingOnly;
// called via RelayCommand
public void UserJustSelectedACar()
{
ObservableCollection<Car> singleItemCollection = new ObservableCollection<Car>();
singleItemCollection.Add(SelectedCar);
_originalCollectionForReferenceKeepingOnly = SelectedCollection;
SelectedCollection = singleItemCollection;
}
public void ReturnToFullUsedCarsList()
{
SelectedCollection = _originalCollectionForReferenceKeepingOnly;
}
EDIT 2
It appears that you are trying to make a ListView pretend to be a "Car Details" view by hiding these other items. This is inherently a bad idea; a different UI element bound to the Listview's Selected Car Item would make for a better solution. Since the new detail panel would just be looking at an already-generated Car instance, you wouldn't incur any data hit. Even if you can make this approach work right now, I'm worried you're going to just cause yourself more grief in the future.

Switch out UserControl based on property

How do I switch UserControls based on a property setting in my ViewModel?
If Vm.View = "A"
<Window>
<local:UserControlA/>
</Window>
If Vm.View = "B"
<Window>
<local:UserControlB/>
</Window>
Vm.View is an enum that someday may allow for C, D, and so on. Both UserControls are bound to the same Vm, but they present the data radically different based on the user's input. So a DataTemplate based on type doesn't really work here.
Thoughts?

Add ContentControl inside Window and based on View value you can set it's ContentTemplate using DataTriggers.
<ContentControl Content="{Binding}">
<ContentControl.Style>
<Style TargetType="ContentControl">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<local:UserControlA/>
</DataTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<DataTrigger Binding="{Binding View}" Value="B">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<local:UserControlB/>
</DataTemplate>
</Setter.Value>
</Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</ContentControl.Style>
</ContentControl>

You might leverage DataTemplate's DataType property and let the binding engine take care of the rest...
XAML
<Window.Resources>
<DataTemplate DataType="localEnums:ProduceType.Apples">
<local:ApplesView />
</DataTemplate>
<DataTemplate DataType="localEnums:ProduceType.Oranges">
<local:OrangesView />
</DataTemplate>
</Window.Resources>
<StackPanel>
<ContentPresenter Content="{Binding ProduceType}" />
<Button Content="Change Produce" Click="Button_Click"/>
</StackPanel>
View Model
public class ProduceViewModel : ViewModel
{
public ProduceViewModel()
{
this.ProduceType = ProduceType.Apples;
}
private ProduceType _produceType;
public ProduceType ProduceType
{
get
{
return _produceType;
}
set
{
if (_produceType != value)
{
_produceType = value;
RaisePropertyChanged();
}
}
}
}
Button Click Handler (Violates pure MVVM but just to demonstrate the DataTemplate switching)
private void Button_Click(object sender, RoutedEventArgs e)
{
(this.DataContext as ProduceViewModel).ProduceType = ProduceType.Oranges;
}

Updating a ListBox with different Content On Button Clicks in WPF

So I have a listbox and a tool bar in my WPF app. The tool bar just has regular controls, and the listbox has vertical expanders.
I need the listbox to have a different set of expanders depending on what button is clicked. Right now it looks like such:
<ListBox>
<local:Select_Analysis_Panel/>
</ListBox>
Where local:Select_Analysis_Panel is seperate user control file containing the expanders. What is the best way to go about dynamically updating the ListBox control's content upon a button click?
For the last couple hours I've been trying to use set DataTemplates for each expander set and bind the to the items control property with little avail with the code below. I'm just trying to get basic framework laid out before setting up a MVVM interface. Later on I was going to replace the ItemsSource="Network_anal" with you know ItemsSource="{Binding WhatExpanderViewModelProperty}" or something like that.
<ListBox Width="250" Margin="5,0,0,0">
<ListBox.Resources>
<DataTemplate DataType="Select_Analysis_Panel">
<local:Select_Analysis_Panel/>
</DataTemplate>
<DataTemplate x:Key="Network_anal" DataType="NetworkAnalysis">
<local:NetworkAnalysis/>
</DataTemplate>.Resources>
<ListBox.Template>
<ControlTemplate>
<Border Background="Red"/>
</ControlTemplate>
</ListBox.Template>
<ItemsControl ItemsSource="Network_anal"/>
</ListBox>
Am I taking the right approach to this at all?
Here's what I'm trying to do. Below when the "File" button is clicked the side bar displays these 2 expanders:
And when "Network Design" button these expanders are dipslayed:

Option 1:
Subclassing the sections:
each of these sections could be subclassed from a base section class and a specific DataTemplate could be used for each:
<Window x:Class="MiscSamples.MultiToolbar"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:MiscSamples"
Title="MultiToolbar" Height="300" Width="300">
<Window.Resources>
<BooleanToVisibilityConverter x:Key="BoolToVisibilityConverter"/>
</Window.Resources>
<DockPanel>
<ListBox ItemsSource="{Binding Sections}"
SelectedItem="{Binding SelectedSection}"
DisplayMemberPath="Name"
DockPanel.Dock="Top">
<ListBox.ItemContainerStyle>
<Style TargetType="ListBoxItem">
<Setter Property="IsEnabled" Value="{Binding IsEnabled}"/>
<Setter Property="Visibility" Value="{Binding IsVisible, Converter={StaticResource BoolToVisibilityConverter}}"/>
<Setter Property="MinWidth" Value="80"/>
<Setter Property="MinHeight" Value="40"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListBoxItem">
<Border BorderBrush="Black" BorderThickness="1">
<ToggleButton IsChecked="{Binding IsSelected, Mode=TwoWay,RelativeSource={RelativeSource TemplatedParent}}">
<ContentPresenter ContentSource="Content"/>
</ToggleButton>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ListBox.ItemContainerStyle>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
</ListBox>
<ScrollViewer Width="300" DockPanel.Dock="Left">
<ContentPresenter Content="{Binding SelectedSection}">
<ContentPresenter.Resources>
<DataTemplate DataType="{x:Type local:FileSection}">
<TextBlock Text="User Control For File Section"/>
</DataTemplate>
<DataTemplate DataType="{x:Type local:NetworkDesignSection}">
<TextBlock Text="User Control For Network Design"/>
</DataTemplate>
<DataTemplate DataType="{x:Type local:SelectAnalysisSection}">
<TextBlock Text="User Control For Select Analysis"/>
</DataTemplate>
</ContentPresenter.Resources>
</ContentPresenter>
</ScrollViewer>
<Grid Background="Gray">
<TextBlock Text="Design Surface" TextAlignment="Center" VerticalAlignment="Center" FontWeight="Bold"/>
</Grid>
</DockPanel>
</Window>
Code Behind:
public partial class MultiToolbar : Window
{
public MultiToolbar()
{
InitializeComponent();
var vm = new MainViewModel();
vm.Sections.Add(new FileSection() {Name = "File"});
vm.Sections.Add(new NetworkDesignSection() { Name = "Network Design" });
vm.Sections.Add(new SelectAnalysisSection() { Name = "Select Analysis" });
DataContext = vm;
}
}
Main ViewModel:
public class MainViewModel: PropertyChangedBase
{
private ObservableCollection<Section> _sections;
public ObservableCollection<Section> Sections
{
get { return _sections ?? (_sections = new ObservableCollection<Section>()); }
}
private Section _selectedSection;
public Section SelectedSection
{
get { return _selectedSection; }
set
{
_selectedSection = value;
OnPropertyChanged("SelectedSection");
}
}
}
Sections:
public abstract class Section:PropertyChangedBase
{
public string Name { get; set; }
private bool _isEnabled = true;
public bool IsEnabled
{
get { return _isEnabled; }
set
{
_isEnabled = value;
OnPropertyChanged("IsEnabled");
}
}
private bool _isVisible = true;
public bool IsVisible
{
get { return _isVisible; }
set
{
_isVisible = value;
OnPropertyChanged("IsVisible");
}
}
//Optionally
//public string ImageSource {get;set;}
//ImageSource = "/Resources/MySection.png";
}
public class FileSection: Section
{
///... Custom logic specific to this Section
}
public class NetworkDesignSection:Section
{
///... Custom logic specific to this Section
}
public class SelectAnalysisSection: Section
{
///... Custom logic specific to File Section
}
//...etc etc etc
Result:
Notice that I'm using ToggleButtons bound to the ListBoxItem.IsSelected property to simulate a TabControl-like behavior.

You can set the DataContext of the whole form and bind the ItemsSource of the listbox, or set ItemsSource of the listbox to some collection directly.