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How to display user control within the main window in WPF using MVVM

I have a WPF application and just embarked in learning MVVM pattern.
My goal is that in my application the main window has a button. When this button is clicked, another window (or user control) will appear on top of the main window.
This is the code of MainWindow.xaml
<Window x:Class="SmartPole1080.View.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:utilities="clr-namespace:SoltaLabs.Avalon.Core.Utilities;assembly=SoltaLabs.Avalon.Core"
xmlns:userControls="clr-namespace:SoltaLabs.Avalon.View.Core.UserControls;assembly=SoltaLabs.Avalon.View.Core"
xmlns:controls="clr-namespace:WpfKb.Controls;assembly=SmartPole.WpfKb"
xmlns:wpf="clr-namespace:WebEye.Controls.Wpf;assembly=WebEye.Controls.Wpf.WebCameraControl"
xmlns:view="clr-namespace:SmartPole.View;assembly=SmartPole.View"
xmlns:view1="clr-namespace:SmartPole1080.View"
xmlns:behaviors="clr-namespace:SoltaLabs.Avalon.Core.Behaviors;assembly=SoltaLabs.Avalon.Core"
Title="Smart Pole"
WindowStartupLocation="CenterScreen"
Name="mainWindow"
behaviors:IdleBehavior.IsAutoReset="True" WindowState="Maximized" WindowStyle="None">
<Canvas Background="DarkGray">
<!--Main Grid-->
<Grid Width="1080" Height="1920" Background="White" Name="MainGrid"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
<StackPanel Background="Black">
<Grid Background="#253341">
<Grid.RowDefinitions>
<RowDefinition Height="5"/>
<RowDefinition Height="*"/>
<RowDefinition Height="5"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="5"/>
<ColumnDefinition Width="264"/>
</Grid.ColumnDefinitions>
<Grid Grid.Row="1" Grid.Column="1">
<Button Tag="{StaticResource EmergencyImg}" Name="EmergencyButton"
Command="{Binding ShowEmergencyPanel}">
<Image Source="{StaticResource EmergencyImg}" />
</Button>
</Grid>
<!--Emergency Window Dialog-->
<Grid Name="EmergencyPanel">
<view1:EmergencyInfo x:Name="EmergencyInfoPanel"/>
</Grid>
</Grid>
</StackPanel>
</Grid>
<!--Main Grid-->
</Canvas>
This is the other window (user control - EmergencyInfo.xaml)
<UserControl x:Class="SmartPole1080.View.EmergencyInfo"
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:local="clr-namespace:SmartPole1080.View"
mc:Ignorable="d"
d:DesignHeight="1920" d:DesignWidth="1050"
x:Name="EmergencyInfoPanel">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="50"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Border Grid.Row="0" BorderBrush="White" Background="White">
<Button Background="White" BorderThickness="0" FontWeight="Bold" Foreground="Red"
HorizontalAlignment="Right" FontSize="25" Margin="0,0,15,0"
Command="{Binding HideEmergencyPanel}">
close X
</Button>
</Border>
<Image Grid.Row="1" Source="{StaticResource EdenParkInfoImg}" HorizontalAlignment="Left" />
</Grid>
I want to implement this behavior using an MVVM pattern. I have set the binding ShowEmergencyPanel in button EmergencyButton to show EmergencyInfo when this button is click.
Any help is greatly appreciated.

Why dont you make navigation, something like this. Make section for conetent that will be injected, and whatever type of object you are expecting put it in Windows.Resources in DataTemplate.
In main windo xaml
<Window.DataContext>
<local:MainWindowViewModel />
</Window.DataContext>
<Window.Resources>
<DataTemplate DataType="{x:Type home:HomeViewModel}">
<home:HomeView />
</DataTemplate>
<DataTemplate DataType="{x:Type other:OtherViewModel}">
<other:OtherView />
</DataTemplate>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid x:Name="Navigation">
<StackPanel Orientation="Horizontal">
<Button x:Name="HomeView"
Content="Home"
Margin="5"
Command="{Binding NavigationCommand}"
CommandParameter="home" />
<Button x:Name="Menu"
Content="OtherView"
Margin="5"
Command="{Binding NavigationCommand}"
CommandParameter="Other" />
</StackPanel>
</Grid>
<Grid x:Name="MainContent"
Grid.Row="1">
<ContentControl Content="{Binding CurrentViewModel}" />
</Grid>
</Grid>
MainWindowViewModel can look something like this.
public class MainWindowViewModel : INotifyPropertyChanged
{
private OtherViewModel otherVM;
private HomeViewModel homeVM;
public DelegateCommand<string> NavigationCommand { get; private set; }
public MainWindowViewModel()
{
otherVM = new OtherViewModel();
homeVM = new HomeViewModel();
// Setting default: homeViewModela.
CurrentViewModel = homeVM;
NavigationCommand = new DelegateCommand<string>(OnNavigate);
}
private void OnNavigate(string navPath)
{
switch (navPath)
{
case "other":
CurrentViewModel = otherVM;
break;
case "home":
CurrentViewModel = homeVM;
break;
}
}
private object _currentViewModel;
public object CurrentViewModel
{
get { return _currentViewModel; }
set
{
if (_currentViewModel != value)
{
_currentViewModel = value;
OnPropertyChanged();
}
}
}
#region INotifyPropertyChanged
public event PropertyChangedEventHandler PropertyChanged = delegate { };
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged(this, new propertyChangedEventArgs(propertyName));
}
#endregion
}
Where DelegateCommand you can make yours,check how to make RelayCommand(and generic one) or use PRISM that have it's own DelegateCommand. But if you want to use PRISM, it allready has navigation to regions, that can solve many problems. Check videos from Brian Lagunas.
EDIT:
This is to show/hide grid. In your mainWindow where you set that EmergencyInfo u can show/hide that grid this way.
in your MainViewViewModel make a bool property IsVisible
private bool _isVisible;
public bool IsVisible
{
get { return _isVisible; }
set
{
_isVisible = value;
OnPropertyChanged();
}
}
in your MainView.Resources set key to BooleanToVisibilityConverter
something like:
<BooleanToVisibilityConverter x:Key="Show"/>
and your grid that you want to show/hide set visibility:
<Grid x:Name="SomeGridName"
Grid.Row="1"
Grid.Colum="1"
Visibility="{Binding IsVisible,Converter={StaticResource Show}}">
And finally set that IsVisible property to some ToggleButton, just to switch between true/false
<ToggleButton IsChecked="{Binding IsVisible}"
Content="ShowGrid" />
This way, you show/hide that grid part based on IsVisible, and you control that visibility onClick. Hope that helps.

Inside your Window xaml:
<ContentPresenter Content="{Binding Control}"></ContentPresenter>
In this way, your ViewModel must contain a Control property.
Add your ViewModel to DataContext of Window.
(For example in window constructor, this.Datacontext = new ViewModel();)
Or another way with interfaces:
public interface IWindowView
{
IUserControlKeeper ViewModel { get; set; }
}
public interface IUserControlKeeper
{
UserControl Control { get; set; }
}
public partial class YourWindow : IViewWindow
{
public YourWindow()
{
InitializeComponent();
}
public IUserControlKeeper ViewModel
{
get
{
return (IUserControlKeeper)DataContext;
}
set
{
DataContext = value;
}
}
}
(In this way, initialize your window where you want to use. Service?)
private IViewWindow _window;
private IViewWindow Window //or public...
{
get{
if(_window==null)
{
_window = new YourWindow();
_window.ViewModel = new YourViewModel();
}
return _window;
}
}
Open your window with one of your UserControls:
void ShowWindowWithControl(object ControlView, INotifyPropertyChanged ControlViewModel, bool ShowAsDialog)
{
if(ControlView is UserControl)
{ //with interface: Window.ViewModel.Control = ...
(Window.DataContext as YourViewModel).Control = (UserControl)ControlView;
if (ControlViewModel != null)
(Window.DataContext as YourViewModel).Control.DataContext = ControlViewModel;
if (ShowAsDialog) //with interface use cast to call the show...
Window.ShowDialog();
else
Window.Show();
}
}

What you can do is, place the Emergency usercontrol inside MainGrid and control its visibility through Model property.
<Canvas Background="DarkGray">
<!--Main Grid-->
<Grid Width="1080" Height="1920" Background="White" Name="MainGrid"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
<StackPanel Background="Black">
<Grid Background="#253341">
<Grid.RowDefinitions>
<RowDefinition Height="5"/>
<RowDefinition Height="*"/>
<RowDefinition Height="5"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="5"/>
<ColumnDefinition Width="264"/>
</Grid.ColumnDefinitions>
<Grid Grid.Row="1" Grid.Column="1">
<Button Tag="{StaticResource EmergencyImg}" Name="EmergencyButton"
Command="{Binding ShowEmergencyPanel}">
<Image Source="{StaticResource EmergencyImg}" />
</Button>
</Grid>
</Grid>
</StackPanel>
<Grid Name="EmergencyPanel">
<view1:EmergencyInfo x:Name="EmergencyInfoPanel" Visibility={Binding IsEmergencyPanelVisible,Converter={StaticResource BoolToVisibilityConverter}} DataContext={Binding} />
</Grid>
</Grid>
<!--Main Grid-->
</Canvas>
By setting proper background to Grid that holding usercontrol, you can achieve modal window like effect.
And you need to have IsEmergencyPanelVisible(default value is false) is your Model, and this property should be changed to true on your button click command.
Note : I guess you are familiar with converters, so i included Converters in my solution.

How to handle item highlight in ListBox when using more than one ListBox using wpf c#

I am using more than one customise ListBox in my application.
I want that when I click on item in one of the ListBox then highlight in other ListBox should be remove .Means I want to select item in one of the ListBox at a time.I provide sample code here
MainWindow.xaml
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="200"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid Grid.Column="0">
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid Grid.Row="0">
<view:ListBox_UserControl x:Name="Control_1"/>
</Grid>
<Grid Grid.Row="1">
<view:ListBox_UserControl x:Name="Control_2"/>
</Grid>
<Grid Grid.Row="2">
<view:ListBox_UserControl x:Name="Control_3"/>
</Grid>
</Grid>
<Grid Grid.Column="1" Background="Aqua">
</Grid>
</Grid>
</Window>
MainWindow.xaml.cs
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
Control_1.ListBox_ItemSource = List_1;
Control_2.ListBox_ItemSource = List_1;
Control_3.ListBox_ItemSource = List_1;
}
List<string> List_1 = new List<string>()
{
"Item_1",
"Item_2",
"Item_3",
"Item_4",
"Item_5"
};
}
ListBox_UserControl.xaml
<Grid>
<ListBox Name="ListBox_1">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding }" MouseLeftButtonDown="TextBlock_MouseLeftButtonDown"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
ListBox_UserControl.xaml.cs
public partial class ListBox_UserControl : UserControl
{
protected event MouseButtonEventHandler TextBlock_Click;
public ListBox_UserControl()
{
InitializeComponent();
}
public List<string> ListBox_ItemSource
{
set
{
ListBox_1.ItemsSource = value;
}
}
private void TextBlock_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
MouseButtonEventHandler handler = TextBlock_Click;
if(handler!=null)
{
handler(sender, e);
}
}
}

Cant update screen (textbox) on button click event for simple calculator application

Iam new to c# windows phone development and Iam attempting to build a simple calculator application using the mvvm design pattern. I have a model class currently with one string variable. this is bound to my calculator screen which is a textbox. I also have a number "1" button. when this is pressed, i want the textbox "screen" to update the value. this is done in a command class that implements ICommand interface. Unfortunately this isnt working currently and I cant figure out where the problem is. below is my model class. its very basic.
namespace PhoneApp2.model
{
public class Sum : INotifyPropertyChanged
{
private string _enteredVal;
public string EnteredVal
{
get { return _enteredVal ; }
set
{
_enteredVal = value;
RaisePropertyChanged("EnteredVal");
}
}
public event PropertyChangedEventHandler PropertyChanged;
public void RaisePropertyChanged(string propName)
{
if (this.PropertyChanged != null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(propName));
}
}
}
next is my xaml file for the mainpage. currently i have the no. 1 button linked to a command class execute() method. and my screen textbox has a binding to my Enteredvalue string. obviously this doesnt look like the ideal way to do it but iam learning it this way as its how some applications are being developed where iam doing an internship.
<Grid x:Name="LayoutRoot" Background="Transparent">
<Grid.Resources>
<commands:UpdateScreenCommand x:Key="myCommand"/>
</Grid.Resources>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="12,17,0,28">
<TextBlock Text="Calculator" Style="{StaticResource PhoneTextNormalStyle}" Margin="12,0"/>
</StackPanel>
<!--ContentPanel - place additional content here-->
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="0,143,0,0" >
<Grid.RowDefinitions>
<RowDefinition Height="1*"/>
<RowDefinition Height="1*"/>
<RowDefinition Height="1*"/>
<RowDefinition Height="1*"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1*"/>
<ColumnDefinition Width="1*"/>
<ColumnDefinition Width="1*"/>
<ColumnDefinition Width="1*"/>
</Grid.ColumnDefinitions>
<Button Content="1" Command="{StaticResource myCommand}" CommandParameter="{Binding}" Height="Auto" Width="Auto" Grid.Row="0" Grid.Column="0"/>
<Button Content="2" Height="Auto" Width="Auto" Grid.Row="0" Grid.Column="1"/>
<Button Content="3" Height="Auto" Width="Auto" Grid.Row="0" Grid.Column="2"/>
<Button Content="+" Height="Auto" Width="Auto" Grid.Row="0" Grid.Column="3"/>
<Button Content="4" Height="Auto" Width="Auto" Grid.Row="1" Grid.Column="0"/>
<Button Content="5" Height="Auto" Width="Auto" Grid.Row="1" Grid.Column="1"/>
<Button Content="6" Height="Auto" Width="Auto" Grid.Row="1" Grid.Column="2"/>
<Button Content="-" Height="Auto" Width="Auto" Grid.Row="1" Grid.Column="3"/>
<Button Content="7" Height="Auto" Width="Auto" Grid.Row="2" Grid.Column="0"/>
<Button Content="8" Height="Auto" Width="Auto" Grid.Row="2" Grid.Column="1"/>
<Button Content="9" Height="Auto" Width="Auto" Grid.Row="2" Grid.Column="2"/>
<Button Content="/" Height="Auto" Width="Auto" Grid.Row="2" Grid.Column="3"/>
<Button Content="0" Height="Auto" Width="Auto" Grid.Row="3" Grid.Column="1"/>
<Button Content="*" Height="Auto" Width="Auto" Grid.Row="3" Grid.Column="3"/>
<Button Content="C" Height="Auto" Width="Auto" Grid.Row="3" Grid.Column="0"/>
<Button Content="=" Height="Auto" Width="Auto" Grid.Row="3" Grid.Column="2"/>
</Grid>
<Grid MinHeight="107" Margin="10,10,0,0" Grid.Row="1" VerticalAlignment="Top" Width="458" RenderTransformOrigin="0.467,-0.089">
<TextBox Height="Auto" Text="{Binding EnteredValue, Mode=OneWay}" TextWrapping="Wrap" VerticalAlignment="Center" Width="Auto" />
</Grid>
</Grid>
and finally I have the command class. the execute method appends the _enteredvalue string. which seems to work when debugging. my issue seems to be coming for the raisepropertychanged method being passed a null. but iam not sure how to fix this.
namespace PhoneApp2.commands
{
public class UpdateScreenCommand : ICommand
{
public bool CanExecute(object parameter)
{
var m = (Sum) parameter;
return true;
}
public event EventHandler CanExecuteChanged;
public void Execute(object parameter)
{
var m = (Sum) parameter;
m.EnteredVal += "1";
}
}
}
again i know this is a bit of a bastardisation of mvvm but iam trying to learn how its implemented where i work. any help is greatly appreciated.

The thing that bothers me the most from your current implementation of MVVM is the Command. Basically we only need to create one class that implements ICommand. Then we can create multiple properties from that class, each can execute different methods/codes. Example implementation of ICommand from another SO post:
public class ActionCommand : ICommand
{
private readonly Action _action;
public ActionCommand(Action action)
{
_action = action;
}
public void Execute(object parameter)
{
_action();
}
public bool CanExecute(object parameter)
{
return true;
}
public event EventHandler CanExecuteChanged;
}
Then we usually put command properties mentioned above in the ViewModel:
public class Sum : INotifyPropertyChanged
{
private ICommand _addOneCommand;
public ICommand AddOneCommand
{
get
{
return _addOneCommand
?? (_addOneCommand = new ActionCommand(() =>
{
EnteredVal += "1";
}));
}
}
.....
.....
}
Assuming Page's DataContext has been set properly to Sum, we can bind the button to Command property in Sum as follows:
<Button Content="1" Command="{AddOneCommand}" Height="Auto" Width="Auto" Grid.Row="0" Grid.Column="0"/>
Some tutorials on getting started with MVVM in Windows Phone application:
geekchamp
msdn
channel9 (this one includes command binding)

Stop ContentTemplate Selector invoke on TabControl selection change event

I have a TabControl. Each tab Item i.e newly added Tab is rendered using content template selector. But each time i switch between the tabs, content template selector is getting called.
I wanted to stop this. This is because, In the in Tabcontrol, User have provided actions to change the layout, since in the selection change event of the tab Item content template is getting called, it is getting difficult for me to retain the layout what user has changed during Tab Item Selection change Event.
Following is code i am using for the TabControl
<TabControl Grid.Column="2" x:Name="MainTabControl" HorizontalAlignment="Stretch" Margin="0,12,0,7"
SelectedItem="{Binding SelectedTabItem}"
Visibility="{Binding TabsVisible}"
ItemsSource="{Binding ToolsList,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
ItemTemplate="{StaticResource ToolDisplayDataTemplate}"
commands:FrameworkUICommandList.TabItemChangedCommand="{Binding Path=TabItemChangedCommand}"
>
<TabControl.ContentTemplate>
<DataTemplate>
<ContentControl Content="{Binding}" ContentTemplateSelector="{DynamicResource toolTabDataItemTemplateSelector}"/>
</DataTemplate>
</TabControl.ContentTemplate>
<TabControl.ItemContainerStyle>
<Style TargetType="TabItem" BasedOn="{StaticResource TabItemStyle}">
<Setter Property="AutomationProperties.AutomationId" Value="{Binding ToolID}" />
<Setter Property="ToolTip" Value="{Binding ToolID,Converter={StaticResource ResourceKey=tabItemTooltipConverter}}"/>
</Style>
</TabControl.ItemContainerStyle>
</TabControl>
UPDATE : I have created a sample project to explain my problem. Could not share the project anywhere, so updating the code snippet in main question. sorry for that.
In the sample project, user can add TabItem dynamically to TabControl. Eash Tabcontent can show two Grid panel and they are separated by Grid Splitter. Display of second grid is Based on some flag (in this example ShowSecondPanel). If user click on "Show / Hide Second Panel" button, then second panel content will be shown for the current selected tab.
The Problem is, user can re-size the panels using Grid Splitter, but when user navigates to some other tab and comes back to previous one, the grid splitter position changes to original position.
Hope I am clear on describing the problem.
Code for MainWindow.xaml
<Window x:Class="TabControlTestApp.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:TabControlTestApp"
Title="MainWindow" Height="500" Width="700">
<Window.DataContext>
<local:MainWindowViewModel />
</Window.DataContext>
<Window.Resources>
<local:TabContentTemplateSelector x:Key="tabContentTemplateSelector" />
<DataTemplate x:Key="TabitemDataTemplate">
<StackPanel Width="50" Height="50">
<TextBlock Text="{Binding TabFirstPanel.Name}"></TextBlock>
</StackPanel>
</DataTemplate>
<DataTemplate x:Key="TabContentWithFirstPanel">
<Grid>
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition></ColumnDefinition>
<ColumnDefinition></ColumnDefinition>
</Grid.ColumnDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0">Name :</TextBlock>
<TextBlock Grid.Row="0" Grid.Column="1" Text="{Binding TabFirstPanel.Name}"></TextBlock>
</Grid>
</DataTemplate>
<DataTemplate x:Key="TabContentWithBothPanel">
<Grid>
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="200"></ColumnDefinition>
<ColumnDefinition Width="5"></ColumnDefinition>
<ColumnDefinition Width="Auto"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Grid Grid.Row="0" Grid.Column="0">
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition></ColumnDefinition>
<ColumnDefinition></ColumnDefinition>
</Grid.ColumnDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0">Name :</TextBlock>
<TextBlock Grid.Row="0" Grid.Column="1" Text="{Binding TabFirstPanel.Name}"></TextBlock>
</Grid>
<GridSplitter Grid.Row="0" Grid.Column="1"
VerticalAlignment="Stretch"
Width="5"
Height="Auto"
ResizeDirection="Columns"
ResizeBehavior="PreviousAndNext"
></GridSplitter>
<Grid Grid.Row="0" Grid.Column="2">
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition></ColumnDefinition>
<ColumnDefinition></ColumnDefinition>
</Grid.ColumnDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0">Additional Detail :</TextBlock>
<TextBlock Grid.Row="0" Grid.Column="1" Text="{Binding TabSecondPanel.AdditionalDetails}"></TextBlock>
</Grid>
</Grid>
</DataTemplate>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="50"></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="150"></ColumnDefinition>
<ColumnDefinition></ColumnDefinition>
</Grid.ColumnDefinitions>
<StackPanel Grid.Row="1" Grid.Column="0">
<Button Content="Load Tab : 1" Name="LoadTab1" Width="100" Height="50" Command="{Binding LoadTabCommand}" CommandParameter="{Binding ElementName=LoadTab1}"></Button>
<Button Content="Load Tab : 2" Name="LoadTab2" Width="100" Height="50" Command="{Binding LoadTabCommand}" CommandParameter="{Binding ElementName=LoadTab2}"></Button>
<Button Content="Load Tab : 3" Name="LoadTab3" Width="100" Height="50" Command="{Binding LoadTabCommand}" CommandParameter="{Binding ElementName=LoadTab3}"></Button>
</StackPanel>
<Button Content="Close All tab" Width="100" Height="40" x:Name="CloseAllTab"></Button>
<Button Content="Show / Hide Second Panel" x:Name="ShowHideSecondPanelInTab"
Grid.Row="0" Grid.Column="1" Width="150"
Command="{Binding LoadTabCommand}" CommandParameter="{Binding ElementName=ShowHideSecondPanelInTab}"></Button>
<TabControl Grid.Row="1" Grid.Column="1"
ItemsSource="{Binding TabContentList,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
SelectedItem="{Binding SelectedTabItem}"
ItemTemplate="{StaticResource ResourceKey=TabitemDataTemplate}"
ContentTemplateSelector="{StaticResource ResourceKey=tabContentTemplateSelector}"
>
</TabControl>
</Grid>
</Window>
Code For MainWindowViewModel
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Input;
using System.ComponentModel;
using System.Collections.ObjectModel;
namespace TabControlTestApp
{
class MainWindowViewModel : INotifyPropertyChanged
{
public MainWindowViewModel()
{
this.loadTabCommand = new LoadTabCommand(this);
tabContentList = new ObservableCollection<TabContent>();
}
public ICommand LoadTabCommand
{
get
{
return this.loadTabCommand;
}
set
{
this.loadTabCommand = value;
}
}
public ObservableCollection<TabContent> TabContentList
{
get
{
return tabContentList;
}
set
{
tabContentList = value;
OnPropertyChanged("TabContentList");
}
}
public TabContent SelectedTabItem
{
get
{
return selectedTabItem;
}
set
{
selectedTabItem = value;
OnPropertyChanged("SelectedTabItem");
}
}
public void LoadFirstTab()
{
TabFirstPanel firstPanel = new TabFirstPanel() { Name = "John-1", Age = "31" };
TabSecondPanel secondPanel = new TabSecondPanel() { AdditionalDetails="Some Details for First Tab" };
TabContent firstTabContent = new TabContent() { TabFirstPanel = firstPanel, TabSecondPanel = secondPanel, ShowSecondPanel = false };
tabContentList.Add(firstTabContent);
SelectedTabItem = firstTabContent;
}
public void LoadSecondTab()
{
TabFirstPanel firstPanel = new TabFirstPanel() { Name = "John-2", Age = "31" };
TabSecondPanel secondPanel = new TabSecondPanel() { AdditionalDetails = "Some Details for second Tab" };
TabContent secondTabContent= new TabContent() { TabFirstPanel = firstPanel, TabSecondPanel = secondPanel, ShowSecondPanel=false };
tabContentList.Add(secondTabContent);
SelectedTabItem = secondTabContent;
}
public void LoadThirdTab()
{
TabFirstPanel firstPanel = new TabFirstPanel() { Name = "John-3", Age = "31" };
TabSecondPanel secondPanel = new TabSecondPanel() { AdditionalDetails = "Some Details for Third Tab" };
TabContent ThirdTabContent = new TabContent() { TabFirstPanel = firstPanel, TabSecondPanel = secondPanel, ShowSecondPanel = false };
tabContentList.Add(ThirdTabContent);
SelectedTabItem = ThirdTabContent;
}
public void ShowHideSecondPanelInTab()
{
TabContent currentTabContent = SelectedTabItem;
int currentIndex = tabContentList.IndexOf(SelectedTabItem);
if (currentTabContent.ShowSecondPanel)
{
currentTabContent.ShowSecondPanel = false;
}
else
{
currentTabContent.ShowSecondPanel = true;
}
TabContentList.RemoveAt(currentIndex);
TabContentList.Insert(currentIndex, currentTabContent);
OnPropertyChanged("TabContentList");
SelectedTabItem = currentTabContent;
}
private TabContent selectedTabItem = null;
private ObservableCollection<TabContent> tabContentList = null;
private ICommand loadTabCommand = null;
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}
Code for TabContentTemplateSelector.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Controls;
using System.Windows;
namespace TabControlTestApp
{
class TabContentTemplateSelector : DataTemplateSelector
{
public override System.Windows.DataTemplate SelectTemplate(object item, System.Windows.DependencyObject container)
{
FrameworkElement element = container as FrameworkElement;
if (element != null && item != null)
{
TabContent tabContent = (TabContent)item;
if (tabContent.ShowSecondPanel)
{
return element.FindResource("TabContentWithBothPanel") as DataTemplate;
}
else
{
return element.FindResource("TabContentWithFirstPanel") as DataTemplate;
}
}
else
{
return base.SelectTemplate(item, container);
}
}
}
}
Code for TabContent Data Object
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace TabControlTestApp
{
class TabFirstPanel
{
public string Name { get; set; }
public string Age { get; set; }
}
class TabSecondPanel
{
public string AdditionalDetails { get; set; }
}
class TabContent
{
public TabFirstPanel TabFirstPanel { get; set; }
public TabSecondPanel TabSecondPanel { get; set; }
public bool ShowSecondPanel { get; set; }
}
}
Code for LoadTabCommand Class
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Input;
namespace TabControlTestApp
{
class LoadTabCommand : ICommand
{
MainWindowViewModel mainWindowViewModel = null;
public LoadTabCommand(MainWindowViewModel mainWindowViewModel)
{
this.mainWindowViewModel = mainWindowViewModel;
}
public bool CanExecute(object parameter)
{
return true;
}
public event EventHandler CanExecuteChanged;
public void Execute(object parameter)
{
System.Windows.Controls.Button btn = (System.Windows.Controls.Button)parameter;
switch (btn.Name)
{
case "LoadTab1":
mainWindowViewModel.LoadFirstTab();
break;
case "LoadTab2":
mainWindowViewModel.LoadSecondTab();
break;
case "LoadTab3":
mainWindowViewModel.LoadThirdTab();
break;
case "ShowHideSecondPanelInTab":
mainWindowViewModel.ShowHideSecondPanelInTab();
break;
}
}
}
}

I took a look at your example. Thanks for posting code. Now I understand your issue completely. Before I suggested to change DynamicResource to StaticResource I thought you wanted to only look up once for your DataTemplate.
Now I see you wish to keep the instance of DataTemplate alive so TabControl doesn't destroy it when changing tabs.
Here is the solution:
<Window.DataContext>
<local:MainWindowViewModel />
</Window.DataContext>
<Window.Resources>
<local:TabContentTemplateSelector x:Key="tabContentTemplateSelector" />
<DataTemplate x:Key="TabitemDataTemplate">
<StackPanel Width="50" Height="50">
<TextBlock Text="{Binding TabFirstPanel.Name}"></TextBlock>
</StackPanel>
</DataTemplate>
<Grid x:Key="template1">
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition></ColumnDefinition>
<ColumnDefinition></ColumnDefinition>
</Grid.ColumnDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0">Name :</TextBlock>
<TextBlock Grid.Row="0" Grid.Column="1" Text="{Binding TabFirstPanel.Name}"></TextBlock>
</Grid>
<Grid x:Key="template2">
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="200"></ColumnDefinition>
<ColumnDefinition Width="5"></ColumnDefinition>
<ColumnDefinition Width="Auto"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Grid Grid.Row="0" Grid.Column="0">
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition></ColumnDefinition>
<ColumnDefinition></ColumnDefinition>
</Grid.ColumnDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0">Name :</TextBlock>
<TextBlock Grid.Row="0" Grid.Column="1" Text="{Binding TabFirstPanel.Name}"></TextBlock>
</Grid>
<GridSplitter Grid.Row="0" Grid.Column="1"
VerticalAlignment="Stretch"
Width="5"
Height="Auto"
ResizeDirection="Columns"
ResizeBehavior="PreviousAndNext"/>
<Grid Grid.Row="0" Grid.Column="2">
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition></ColumnDefinition>
<ColumnDefinition></ColumnDefinition>
</Grid.ColumnDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0">Additional Detail :</TextBlock>
<TextBlock Grid.Row="0" Grid.Column="1" Text="{Binding TabSecondPanel.AdditionalDetails}"></TextBlock>
</Grid>
</Grid>
<DataTemplate x:Key="TabContentWithFirstPanel">
<ContentPresenter Content="{StaticResource template1}"/>
</DataTemplate>
<DataTemplate x:Key="TabContentWithBothPanel">
<ContentPresenter Content="{StaticResource template2}"/>
</DataTemplate>
If you just copy past that you will do fine.
By the way, just as sidenote for you, destroying and building up DataTemplates is very important in wpf for releasing unmanaged memory.

I don't believe you may avoid this behavior, unless you use another control other than the TabControl.
The TabControl is a ItemControl-derived component: if its content is created via DataTemplate (as you done), the actual content is generated every time upon the current selection.
Another option is to fill the TabControl with direct content, and the inner controls should be preserved across the selection.
Have a look here:
http://msdn.microsoft.com/en-us/library/system.windows.controls.tabcontrol(v=vs.110).aspx
UPDATE: First off, I am not sure to have understand what you want, but here is a solution based on what I mean.
The fundamental trick is hosting directly the tab-contents, instead of creating via data-templating. That is:
<TabControl>
<TabItem Header="Tab1">
<TextBlock
Text="Page 1"
HorizontalAlignment="Center"
VerticalAlignment="Center"
/>
</TabItem>
<TabItem Header="Tab2">
<CheckBox
Content="check me"
HorizontalAlignment="Center"
VerticalAlignment="Center"
/>
</TabItem>
<TabItem Header="Tab3">
<TextBlock
Text="Page 3"
HorizontalAlignment="Center"
VerticalAlignment="Center"
/>
</TabItem>
</TabControl>
The above snippet should "persist" the checkbox value across the tabs flipping.
But you need (or desire) some kind of templating, or a dynamic way to create the right content upon a certain data added to the tabcontrol.
The following trick should solve your problem:
<TabControl>
<TabItem
Header="Tab1"
>
<ContentControl
Content="{Binding Path=A}"
ContentTemplateSelector="{StaticResource sel}"
/>
</TabItem>
<TabItem
Header="Tab2"
>
<ContentControl
Content="{Binding Path=B}"
ContentTemplateSelector="{StaticResource sel}"
/>
</TabItem>
<TabItem
Header="Tab3"
>
<ContentControl
Content="{Binding Path=C}"
ContentTemplateSelector="{StaticResource sel}"
/>
</TabItem>
</TabControl>
This is using a trivial set of templates as follows:
<Window.Resources>
<local:MySelector x:Key="sel" />
<DataTemplate x:Key="dtplA">
<StackPanel Margin="30,30">
<TextBlock Text="A: " />
<TextBox />
</StackPanel>
</DataTemplate>
<DataTemplate x:Key="dtplB">
<StackPanel Margin="30,30">
<TextBlock Text="B: " />
<TextBox />
</StackPanel>
</DataTemplate>
<DataTemplate x:Key="dtplC">
<StackPanel Margin="30,30">
<TextBlock Text="C: " />
<TextBox />
</StackPanel>
</DataTemplate>
</Window.Resources>
And the behind-code is even more trivial:
public class VM
{
public A A { get; set; }
public B B { get; set; }
public C C { get; set; }
}
public class A { }
public class B { }
public class C { }
public class MySelector : DataTemplateSelector
{
public override DataTemplate SelectTemplate(object item, DependencyObject container)
{
if (item != null)
{
return (DataTemplate)((FrameworkElement)container).FindResource("dtpl" + item.GetType().Name);
}
else
{
return base.SelectTemplate(item, container);
}
}
}
If you try this small example, the text typed into the textboxes will persist across the tabs flipping. That is, the templates will be called once only.
Let me know.

Multiple Datatemplates & Grid.IsSharedSizeScope - Not aligning to content width

I have a listbox in which I render data using multiple datatemplates, and I use a datatemplate selector to route data to the appropriate template.
Each template has it's own layout using a grid. The first column of every grid inside the template is a textblock and I want them aligned to left. The next item is another textblock which should be aligned towards the maximum width of the first textblock (something similar to a data entry form). I'm using Grid.IsSharedSizeScope for this, but not able to achieve this. Below is my code:
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Page.Resources>
<DataTemplate x:Key="DefaultTemplate">
<Border BorderThickness="1" CornerRadius="3" BorderBrush="LightGray">
<TextBlock Text="{Binding Name}"></TextBlock>
</Border>
</DataTemplate>
<DataTemplate x:Key="ShortFieldTemplate">
<Grid Grid.IsSharedSizeScope="True">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" SharedSizeGroup="A"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<TextBlock Text="Age:" Grid.Column="0"></TextBlock>
<TextBlock Text="{Binding Age}" Grid.Column="1"></TextBlock>
</Grid>
</DataTemplate>
<DataTemplate x:Key="LongFieldTemplate">
<Grid Grid.IsSharedSizeScope="True">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" SharedSizeGroup="A"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<TextBlock Text="This should be the name:" Grid.Column="0"></TextBlock>
<TextBlock Text="{Binding Name}" Grid.Column="1"></TextBlock>
</Grid>
</DataTemplate>
<GridSplitterTextTrim:MyFirstTemplateSelector x:Key="MyFirstTemplateSelector"
DefaultDataTemplate="{StaticResource DefaultTemplate}"
ShortFieldDataTemplate="{StaticResource ShortFieldTemplate}"
LongFieldDataTemplate="{StaticResource LongFieldTemplate}"
/>
</Page.Resources>
<Grid x:Name="LayoutRoot" Grid.IsSharedSizeScope="True">
<Grid Grid.Column="2" Background="Green" >
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<ListBox ItemsSource="{Binding Items}" Grid.Row="0" Grid.Column="0" x:Name="listbox" ItemTemplateSelector="{StaticResource MyFirstTemplateSelector}">
</ListBox>
</Grid>
</Grid>
</Page>
..and my object model
public class ShortField : INotifyPropertyChanged
{
private string _name;
public string Age
{
get { return _name; }
set
{
_name = value;
InvokePropertyChanged(new PropertyChangedEventArgs("Age"));
}
}
private string _currentValue;
public string CurrentValue
{
get { return _currentValue; }
set
{
_currentValue = value;
InvokePropertyChanged(new PropertyChangedEventArgs("CurrentValue"));
}
}
public event PropertyChangedEventHandler PropertyChanged;
public void InvokePropertyChanged(PropertyChangedEventArgs e)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null) handler(this, e);
}
public static List<ShortField> GetShortFields()
{
return new List<ShortField>()
{
new ShortField() {Age = "10"},
new ShortField() {Age = "21"},
};
}
}
How do I get this alignment right? I thought Grid.IsSharedScope should do the trick. Is that correct or is there any other way?
Thanks in advance,
-Mike

try to set
<ListBox Grid.IsSharedSizeScope="True"