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C# WPF use properties from different usercontrol as Command parameter

I have a problem with referencing properties or elements on different user controls in my MVVM WPF application.
Edit: Reduced code to a MCVE (hopefully). Also removed PropertyChanged Events to reduce code.
TLDR
I split up all my MainWindow.xaml elements to different user controls
In the menubar (one control) I want to fire a ICommand to save a Settings object (which is the datacontext of the MainWindow
For the method that is called in the Command I need a value from a completely different UserControl that is neither parent nor child of the menubar
How can I retrieve the value from the PasswordBox in a MVVM approach (most preferably as the CommandParameter on the MenuBar)?
View
MainWindow.xaml
<Window x:Class="WpfApp1.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:ViewModel="clr-namespace:WpfApp1.ViewModel"
xmlns:View="clr-namespace:WpfApp1.View"
xmlns:local="clr-namespace:WpfApp1"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Window.DataContext>
<ViewModel:SettingsViewModel/>
</Window.DataContext>
<StackPanel>
<DockPanel>
<View:MenuBar DataContext="{Binding}"/>
</DockPanel>
<TabControl>
<TabItem Header="Tab1" DataContext="{Binding AppSettings}">
<View:TabItemContent/>
</TabItem>
</TabControl>
</StackPanel>
</Window>
The MenuBar which is supposed to bind on ICommand properties on the ViewModel (the DataContext of MainWindow).
MenuBar.xaml
<UserControl x:Class="WpfApp1.View.MenuBar"
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:WpfApp1.View"
mc:Ignorable="d"
d:DesignHeight="450" d:DesignWidth="800" >
<Menu DockPanel.Dock="Top" Height="Auto" >
<!-- In the command I need a reference to the password on the tabItem -->
<MenuItem Name="SaveItem" Height="Auto" Header="Save"
Command="{Binding SaveCommand}"
CommandParameter="Binding RelativeSource=
{RelativeSource FindAncestor, AncestorType={x:Type UserControl}}}"/>
</Menu>
</UserControl>
TabItemContent.xaml
<UserControl x:Class="WpfApp1.View.TabItemContent"
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:WpfApp1.View"
mc:Ignorable="d"
d:DesignHeight="450" d:DesignWidth="800"
DataContext="{Binding PasswordSettings}">
<Grid>
<PasswordBox Height="25" Width="100" />
</Grid>
</UserControl>
In TabItemControl.xaml.cs I tried to introduce a Dependency Property and set the value to the datacontext of the control.
ViewModel
SettingViewModel.cs
using System.ComponentModel;
using System.Runtime.CompilerServices;
using System.Windows.Input;
using WpfApp1.Commands;
using WpfApp1.Model;
namespace WpfApp1.ViewModel
{
public class SettingsViewModel
{
public Settings AppSettings { get; private set; } = new Settings();
public ICommand SaveCommand { get; private set; }
public SettingsViewModel()
{
SaveCommand = new DelegateCommand( SaveSettings );
// load settings and call
// OnPropertyChanged( "AppSettings" );
}
public void SaveSettings( object o = null )
{
if( o is string encryptedPass )
{
// get the password and save it to AppSettings object
}
// call save method on settings
}
}
}
Model (Setting classes)
AppSetting.cs (encapsulating all the setting objects from the other tabs)
namespace WpfApp1.Model
{
public class Settings
{
public PasswordSettings PwSettings { get; set; } = new PasswordSettings();
}
}
PasswordSettings.cs
namespace WpfApp1.Model
{
public class PasswordSettings
{
public string EncryptedPass { get; set; }
}
}
and finally the DelegateCommand implementation in
DelegateCommand.cs see this gist

In a WPF application using Visual Studio, how can I bind a usercontrol to a usercontrol variable?

I'm not sure if I asked the question correctly, because I am not finding the answer by searching the internet. I am creating a wizard window. I have a window that has a title at the top and buttons at the bottom that will stay there throughout changing the pages. So in the xaml.cs for the window, I have a list of UserControls that will contain all of the views for the wizard. I also have a property/field that holds the current view. I want to create a xaml UserControl tag that binds to the current view property. It should change when I change the current view property (I have already implemented the INotifyChanged interface). The current view property will be changed by c#. Here is the code that I have(simplified to show whats needed), and when I run it nothing shows in the view area:
WizardWindow.xaml:
<Window x:Class="WizardWindow.WizardWindow"...>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="70"/>
<RowDefinition Height="*"/>
<RowDefinition Height="50"/>
</Grid.RowDefinitions>
<Grid Grid.Row="0">
<TextBlock Text="Wizard Title"/>
</Grid>
<Grid Grid.Row="1">
<Border Name="WizardWindowPageContent" Margin="5" BorderBrush="Black" BorderThickness="1">
<!--This is what I have tried but isn't working -->
<UserControl Content="{Binding CurrentView}" />
</Border>
</Grid>
<Grid Grid.Row="2" Name="WizardButtons">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Button Grid.Column="0">Cancel</Button>
<Button Grid.Column="2">Back</Button>
<Button Grid.Column="3">Next</Button>
</Grid>
</Grid>
</Window>
WizardWindow.xaml.cs:
using System;
...
using System.Windows.Controls;
namespace WizardWindow
{
public partial class WizardWindow : Window, INotifyPropertyChanged
{
// List of views in the config window
private List<UserControl> views;
// Current view showing in the window
private UserControl currentView;
public UserControl CurrentView
{
get { return currentView; }
set
{
currentView = value;
OnPropertyChanged("CurrentView");
}
}
// Used to keep track of the view index
private int viewIndex;
public WizardWindow ()
{
InitializeComponent();
// Set the screen to the center of the screen
WindowStartupLocation = System.Windows.WindowStartupLocation.CenterScreen;
views = new List<UserControl>();
views.Add(new FirstWizardPage(this));
viewIndex = 0;
CurrentView = views[viewIndex];
}
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(string info)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null)
{
handler(this, new PropertyChangedEventArgs(info));
}
}
}
}
FirstWizardPage.xaml:
<!-- This should show up in the window -->
<UserControl x:Class="WizardWindow.FirstWizardPage" ... >
<Grid>
<TextBlock>Lorem Ipsum ...</TextBlock>
</Grid>
</UserControl>
FirstWizard.xaml.cs:
using System.Windows.Controls;
namespace WizardWindow
{
public partial class FirstWizardPage : UserControl
{
public FirstWizardPage(WizardWindow window)
{
InitializeComponent();
}
}
}
The given possible duplicate, Window vs Page vs UserControl for WPF navigation?
, is a good solution if I wanted to rewrite my program. However, it is not a solution to my exact problem. Someone else might have a similar problem and need this solution.

you need to use this:
<ContentControl x:Name="MyView"
Content="{Binding CurrentView}" />
It should work for you, but it's not MVVM.

You must binding on property DataContext of your user control, if you want to use MVVM.
I Will show little example for you:
It is MainWindow.xaml:
<Window x:Class="WpfApp2.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:WpfApp2"
xmlns:cefSharp="clr-namespace:CefSharp.Wpf;assembly=CefSharp.Wpf"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Grid>
<local:Foo DataContext="{Binding UserControlViewModel}"/>
</Grid>
It is MainWindow.xaml.cs:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
DataContext = new MainWindowViewModel();
}
}
It is MainWindowViewModel.cs:
public class MainWindowViewModel
{
public MainWindowViewModel()
{
UserControlViewModel = new UserControlViewModel{ Name = "Hello World" };
}
public UserControlViewModel UserControlViewModel { get; }
}
It is Foo.xaml:
<UserControl x:Class="WpfApp2.Foo"
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:WpfApp2"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300">
<Grid>
<TextBlock Text="{Binding Name}"/>
</Grid>
It is FooUsercontrolViewModel.cs
public class FooUserControlViewModel
{
public string Name { get; set; }
}

WPF controls not showing up in ItemTemplate(Listbox/ListView)

I have recently started with XAML and WPF. I just created a new project in wpf and add the below XAML code. But...none of the items which are added inside "Listbox.ItemTemplate" or "ListView.ItemTemplate" for that matter show up in designer window. what am i doing wrong? This is a fresh project and so no code-behind stuff added yet. i scratched my head for 15 mins with this but with no success. Please help
<Window x:Class="WpfApplication3.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Grid Margin="10">
<ListBox Margin="10">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="Name: " />
<TextBlock Text="Age: " />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Window>

You should bind your ListBox or entire Window to some DataContext (usually this is viewmodel with the data you need to display) or specify items of the list explicitly.
In your snippet you specified only an item template, not the items itself.
The example of XAML-defined items (simple strings):
<Window x:Class="WpfApplication3.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Grid Margin="10">
<ListBox Margin="10">
<ListBox.Items>
<ListBoxItem>123</ListBoxItem>
<ListBoxItem>456</ListBoxItem>
</ListBox.Items>
</ListBox>
</Grid>
</Window>
The example with DataContext and Bindings.
XAML:
<Window x:Class="WpfApplication3.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Grid Margin="10">
<ListBox Margin="10" ItemsSource="{Binding Path=Persons}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Label>Name:</Label><TextBlock VerticalAlignment="Center" Text="{Binding Path=Name}" />
<Label>Age:</Label><TextBlock VerticalAlignment="Center" Text="{Binding Path=Age}" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Window>
Codebehind:
namespace WpfApplication3
{
public class PersonViewModel
{
public PersonViewModel(string name, int age)
{
this.name = name;
this.age = age;
}
public string Name
{
get { return name; }
}
private string name;
public int Age
{
get { return age; }
}
private int age;
}
public class MainViewModel
{
public MainViewModel()
{
persons = new ObservableCollection<PersonViewModel>()
{
new PersonViewModel("Lez", 146),
new PersonViewModel("Binja", 158),
new PersonViewModel("Rufus the Destroyer", 9000)
};
}
public ObservableCollection<PersonViewModel> Persons
{
get { return persons; }
}
private ObservableCollection<PersonViewModel> persons;
}
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.DataContext = new MainViewModel();
}
}
}
IMPORTANT: Don't forget to properly implement INotifyPropertyChanged in case of mutable properties of viewmodels (for example, if you will have setters for "Name" and "Age" properties of PersonViewModel).

You don't see any items because your ListBox doesn't contain any data in the designer view. To populate it, a list should be binded to the property "ItemsSource" of your ListBox, or adding datas directly to the property "Items" (XAML or code behind).
If you want to show items in the designer view properly, you should have a ViewModel binding to the DataContext of your page and create a "Sample data" file (via Blend for example).

Item Templates are basically used to show customize data. Just Use simple string items first. It will show in list box.

How to bind a property in the view model of a usercontrol to a property in another usercontrol

I am currently working within a WPF user control using MVVM. My MainWindow.xaml looks like below.
MainWindow.xaml
<Window.Resources>
<ObjectDataProvider x:Key="TabsList" ObjectType="{x:Type local:MainWindowModel}" MethodName="GetTabs"/>
</Window.Resources>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<ListBox Grid.Column="0" ItemsSource="{Binding Source={StaticResource TabsList}}" IsSynchronizedWithCurrentItem="True">
<ListBox.ItemTemplate>
<DataTemplate>
<Label Content="{Binding Path=TabName}" Margin="10"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<ContentControl Grid.Column="1" Content="{Binding Source={StaticResource TabsList}, Path=MyUserControl}"/>
</Grid>
Data provider class is as below
public class MainWindowModel
{
public List<TabInfo> GetTabs()
{
return new List<TabInfo>()
{
new TabInfo() { TabName="Tab1", MyUserControl = new UserControl1()},
new TabInfo() { TabName="Tab2", MyUserControl = new UserControl2()}
};
}
}
public class TabInfo
{
public string TabName { get; set; }
public UserControl MyUserControl { get; set; }
}
And now I have two usercontrols UserControl1 and UserControl2 each has a text box control. I would like to update the Text property of the textbox control in the UserControl1 whenever the Text property of the Textbox control in the UserControl2 is updated. To do this, I tried as below.
UserControl1
<UserControl x:Class="MoreOnBinding2.UserControl1"
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"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300">
<Grid>
<TextBox Width="200" Height="20" Text="{Binding Path=UserControl1Text}"/>
</Grid>
UserControl1ViewModel
public class UserControl1VM : ViewModelBase
{
public UserControl1VM()
{
this.UserControl1Text = "10";
}
private string userControl1Text;
public string UserControl1Text
{
get { return userControl1Text; }
set
{
if (userControl1Text != value)
{
userControl1Text = value;
RaisePropertyChanged(() => UserControl1Text);
}
}
}
}
UserControl2
<UserControl x:Class="MoreOnBinding2.UserControl2"
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:MoreOnBinding2"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300">
<Grid>
<TextBox Width="200" Height="20"
Text="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type local:UserControl1}},
UpdateSourceTrigger=PropertyChanged, Path=UserControl1Text}" />
</Grid>
But it is not working. It seems there is a problem in the RelativeSource tag in the UserControl2. Can someone help on this.

You could use a Dependency Property on your user controls this would give you a bind able property. see link
EDIT 1
Just had another look at your class setup. If you are following the MVVM approach I don't think you should have a reference to your user control in your view model
View Model should be more Like
public Class
{
ObservableCollection<TabInfo> _Tabs = new ObservableCollection<TabInfo>();
public ObservableCollection<TabInfo> Tabs
{
get{return _Tabs;}
set {_Tabs = value;}//Need to implement INotifyPropertyChanged [Link][2]
}
public TabInfo SelectedTab {get;set;}
}
public class TabInfo
{
public string TabName { get; set; }
public UserControlViewModel MyUserControlViewModel{ get; set; }
}
Then in your View
<Window.DataContext>
<vm:MainWindowModel />
</Window.DataContext>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<ListBox Grid.Column="0" ItemsSource="{Binding Tabs}" IsSynchronizedWithCurrentItem="True" SelectedValue="{Binding SelectedTab}">
<ListBox.ItemTemplate>
<DataTemplate>
<Label Content="{Binding Path=TabName}" Margin="10"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<ContentControl Grid.Column="1" Content="{Binding SelectedTab.MyUserControlViewModel"/>
</Grid>
This should give you a list of Tabs and then when one is selected it will set the content of the ContentControl to the MyUserControlViewModel.
You would then need to use some sort of template selector to control the ContentTemplate to load different UserControls into the ContentControl
I haven't tested the code works and you would need to implement the INotifyPropertyChanged on all the public properties so the bindings update as the properties value is changed.
Hope that helps a bit.

Custom dependency property binding

I got some problem with custom dependency property binding.
We have:
Custom user control with one dependency property and binding to self:
<UserControl x:Class="WpfApplication1.SomeUserControl"
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"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300" DataContext="{Binding RelativeSource={RelativeSource Mode=Self}}">
<Grid>
<Label>
<Label.Template>
<ControlTemplate>
<Label Content="{Binding MyTest}"/>
</ControlTemplate>
</Label.Template>
</Label>
</Grid>
... and code of control:
public partial class SomeUserControl : UserControl
{
public SomeUserControl()
{
InitializeComponent();
}
public static readonly DependencyProperty MyTestProperty = DependencyProperty.Register("MyTest", typeof(int), typeof(SomeUserControl));
public int MyTest
{
get { return (int)GetValue(MyTestProperty); }
set { SetValue(MyTestProperty, value); }
}
}
I trying to use this control with binding to some simple property of simple model class:
<UserControl x:Class="WpfApplication1.AnotherUserControl"
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:wpfApplication1="clr-namespace:WpfApplication1"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300" DataContext="{Binding RelativeSource={RelativeSource Mode=Self}}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<wpfApplication1:SomeUserControl MyTest="{Binding Path=Model.MyNum}" Grid.Column="0"/>
<Label Content="{Binding Path=Model.MyNum}" Grid.Column="1"/>
</Grid>
... with code
public partial class AnotherUserControl : UserControl
{
public MyModel Model { get; set; }
public AnotherUserControl()
{
Model = new MyModel();
Model.MyNum = 1231;
InitializeComponent();
}
}
... and model:
public class MyModel:INotifyPropertyChanged
{
private int _myNum;
public int MyNum
{
get { return _myNum; }
set { _myNum = value; OnPropertyChanged("MyNum");}
}
public event PropertyChangedEventHandler PropertyChanged;
[NotifyPropertyChangedInvocator]
protected virtual void OnPropertyChanged(string propertyName)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}
}
But binding is not working. Stack have no errors in compilation. Now, binding working with statndart wpf label control (with same model), and don't working with my custom control and custom property. Please help me to understand reasons of this problem and solve it;
Thanks)

You should use ElementName Binding in your SomeUserControl.
<UserControl x:Class="WpfApplication1.SomeUserControl"
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"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300"
x:Name="uc">
<Grid>
<Label>
<Label.Template>
<ControlTemplate>
<Label Content="{Binding MyTest, ElementName=uc}"/>
</ControlTemplate>
</Label.Template>
</Label>
</Grid>
here some more information why you should not set the datacontext of a usercontrol to self/this.
Data Binding in WPF User Controls

You will need to update your binding as below i.e you will have to bind to the ancestor usercontrol property using RelativeSource as you are setting the DataContext of child usercontrol explicitly, default binding will search for path inside the child userControl's DataContext.
<wpfApplication1:SomeUserControl MyTest="{Binding Path=DataContext.Model.MyNum, RelativeSource={RelativeSource FindAncestor={x:Type UserControl}}}" Grid.Column="0"/>