I need tips from you guys, I hope someone can help me.
I want to make a WPF application which has a navigation header.
By navigation header I mean: I want to have a grid on top that contains buttons and when you click on the buttons, the bottom grid should show a completely different view. These views can also contain buttons and when clicking on these buttons only the lower grid should be updated and the top should remain as it is.
Also i want to use MVVM in my application.
below in the code you could better understand what I mean
`
<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:local="clr-namespace:WpfApp1"
mc:Ignorable="d"
Title="MainWindow"
Height="450"
Width="800">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid Grid.Row="0" Background="Red"> <!--this should be the header for the application-->
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Button Grid.Column="0" Content="View 1" Margin="4"/>
<Button Grid.Column="1" Content="View 2" Margin="4"/>
</Grid>
<Grid Grid.Row="1" Background="LightBlue">
<Label Content="View 1/ View 2 Content" FontSize="24" HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Grid>
</Grid>
</Window>
`
enter image description here
In addition to what Yannick pointed out for the visibility converter, I would do the following.
Create two additional "UserControl" classes (similar xaml markup as your window, but have each user control draw just what IT is to represent. This way, if you need to move the stuff around, you fix that one control. It still resides within your outer main window. For example.
<Window x:Class="NavigationHeader.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:NavigationHeader"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Window.Resources>
<BooleanToVisibilityConverter x:Key="BoolToVisConv" />
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid Grid.Row="0" Background="Red">
<!--this should be the header for the application-->
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Button Grid.Column="0" Content="View 1" Margin="4" Command="{Binding View1Command}"/>
<Button Grid.Column="1" Content="View 2" Margin="4" Command="{Binding View2Command}"/>
</Grid>
<local:MyFirstControl
Grid.Row="1"
Background="LightCoral"
Visibility="{Binding View1Visibility,
Converter={StaticResource BoolToVisConv}}" />
<local:MySecondControl
Grid.Row="1"
Background="LightBlue"
Visibility="{Binding View2Visibility,
Converter={StaticResource BoolToVisConv}}" />
</Grid>
</Window>
<UserControl x:Class="NavigationHeader.MyFirstControl"
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:NavigationHeader"
mc:Ignorable="d" >
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="50" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Label Grid.Row="0" Grid.Column="0"
Content="View 1" FontSize="24"
HorizontalAlignment="Center" VerticalAlignment="Center"/>
<TextBox Grid.Row="0" Grid.Column="1"
Text="my content" Width="100" Margin="10"/>
<Button Grid.Row="2" Grid.Column="2"
Content="Ok" Width="50" />
</Grid>
</UserControl>
<UserControl x:Class="NavigationHeader.MySecondControl"
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:NavigationHeader" >
<StackPanel>
<Label Content="View 1"
FontSize="24"
HorizontalAlignment="Center" VerticalAlignment="Center"/>
<TextBox Text="my content" Width="100" Margin="10"/>
<Button Content="Ok" Width="50" Margin="10"/>
</StackPanel>
</UserControl>
Notice the main window is referencing two more classes you would create as a user control MyFirstControl and MySecondControl. This can help keep your clutter in each respective control vs bloating the main control up and worrying about different formats such as one using a grid, and the other using a stack panel, docking panel, or whatever other type control you want to display.
I've used the community toolkit nuget package for the following. This implements inpc for me and generates some code using attributes.
The basic principle of what follows is called viewmodel first navigation. You should be able to find examples out there on the web explain more fully if you like.
To navigate this switches out a viewmodel instance which is then datatemplated into the view, with the viewmodel as datacontext.
Mainwindow
<Window.Resources>
<DataTemplate DataType="{x:Type local:AlphaViewModel}">
<local:AlphaView/>
</DataTemplate>
<DataTemplate DataType="{x:Type local:BetaViewModel}">
<local:BetaView/>
</DataTemplate>
<DataTemplate DataType="{x:Type local:GammaViewModel}">
<local:GammaView/>
</DataTemplate>
</Window.Resources>
<Window.DataContext>
<local:MainWindowViewModel/>
</Window.DataContext>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid Grid.Row="0" Background="Red">
<!--this should be the header for the application-->
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Button Command="{Binding NavigateViewModelCommand}"
CommandParameter="{x:Type local:AlphaViewModel}"
Content="Alpha" Grid.Column="0" Margin="4"/>
<Button Command="{Binding NavigateViewModelCommand}"
CommandParameter="{x:Type local:BetaViewModel}"
Content="Beta" Grid.Column="1" Margin="4"/>
</Grid>
<Grid Grid.Row="1" Background="LightBlue">
<ContentPresenter Content="{Binding CurrentViewModel}"/>
</Grid>
</Grid>
Notice how viewmodel types are associated with usercontrols. Where an alphaviewmodel is presented to the view, it will be datatemplates with an alphaview.
Buttons bind to a command and pass a type as a parameter.
The contentpresenter is where that viewmodel will be presented to the view.
That's bound to CurrentViewModel.
MainWindowViewModel
using CommunityToolkit.Mvvm.Input;
namespace WpfVMFirst
{
public partial class MainWindowViewModel : ObservableObject
{
[ObservableProperty]
private object? currentViewModel = new GammaViewModel();
[RelayCommand]
private void NavigateViewModel(Type type)
{
var vm = Activator.CreateInstance(type);
CurrentViewModel = null;
CurrentViewModel = vm;
}
}
}
NavigateViewModel will become that NavigateViewModelCommand due to code generation.
It takes the type I mentioned above and is going to generically instantiate a viewmodel from that.
If you wanted to retain state between navigations, you could cache in a dictionary and re-use a viewmodel if it was already there.
Seting the currentviewmodel to null forces re templating. If you navigate to the same viewmodel it will force a new instance of the view usercontrol.
One of my usercontrols has a button of it's own:
Beta:
<Grid Background="Blue">
<TextBlock Text="Beta"/>
<Button HorizontalAlignment="Right"
Content="Gamma"
VerticalAlignment="Top"
Command="{Binding DataContext.NavigateViewModelCommand, RelativeSource={RelativeSource AncestorType=Window}}"
CommandParameter="{x:Type local:GammaViewModel}"/>
</Grid>
</UserControl>
Click that button and the view is navigated to gamma.
That command works because it's using relativesource to look up the visual tree to the window, then use the command out the window's datacontext
Other viewmodels and usercontrols are pretty minimal. I have nothing in the alpha, beta and gamma viewmodels since this is just for demo purposes.
AlphaView
<Grid Background="Red">
<TextBlock Text="Alpha"/>
</Grid>
That wiring up connecting viewmodel to view type can be put into a resource dictionary merged in app.xaml.
In "real" apps the viewmodels are likely to have all sorts of functionality in them and it's usual to dependency inject those. The instantiation would be a bit more sophisticated.
As is reading any data such viewmodels require.
It's common to have an IGetData interface they implement with a GetData asynchronous task so they can be instantiated using a minimal CTOR and the data then retrieved using that abstracted method.
This is a mainstream commercial pattern which I've used and seen used successfully in real world single window apps.
Here is a begining :
Encapsulate each view in a Grid and manage their visibility in the View Model. A simple solution if you are starting with MVVM.
THE MAIN VIEW
<Window x:Class="NavigationHeader.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:NavigationHeader"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Window.Resources>
<BooleanToVisibilityConverter x:Key="BoolToVisConv" />
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid Grid.Row="0" Background="Red">
<!--this should be the header for the application-->
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Button Grid.Column="0" Content="View 1" Margin="4" Command="{Binding View1Command}"/>
<Button Grid.Column="1" Content="View 2" Margin="4" Command="{Binding View2Command}"/>
</Grid>
<Grid Grid.Row="1" Background="LightCoral" Visibility="{Binding View1Visibility, Converter={StaticResource BoolToVisConv}}">
<StackPanel>
<Label Content="View 1" FontSize="24" HorizontalAlignment="Center" VerticalAlignment="Center"/>
<TextBox Text="my content" Width="100" Margin="10"/>
<Button Content="Ok" Width="50" Margin="10"/>
</StackPanel>
</Grid>
<Grid Grid.Row="1" Background="LightBlue" Visibility="{Binding View2Visibility, Converter={StaticResource BoolToVisConv}}">
<Label Content="View 2" FontSize="24" HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Grid>
</Grid>
</Window>
THE MAIN VM
For the View Model you need to install the Nuget's Package CommunityToolkit.Mvvm as the Main VM needs these namespaces:
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
public class MainVM : ObservableObject
{
private bool myView1Visibility;
private bool myView2Visibility;
public MainVM()
{
myView1Visibility = false;
myView2Visibility = false;
}
public bool View1Visibility
{
get { return myView1Visibility; }
set
{
if (value == myView1Visibility) return;
myView1Visibility = value;
OnPropertyChanged(nameof(View1Visibility));
}
}
public bool View2Visibility
{
get { return myView2Visibility; }
set
{
if (value == myView2Visibility) return;
myView2Visibility = value;
OnPropertyChanged(nameof(View2Visibility));
}
}
RelayCommand myView1Command;
RelayCommand myView2Command;
public RelayCommand View1Command
{
get
{
if (myView1Command == null)
myView1Command = new RelayCommand(View1CommandAction);
return myView1Command;
}
}
public RelayCommand View2Command
{
get
{
if (myView2Command == null)
myView2Command = new RelayCommand(View2CommandAction);
return myView2Command;
}
}
private void View1CommandAction()
{
View2Visibility = false;
View1Visibility = true;
}
private void View2CommandAction()
{
View1Visibility = false;
View2Visibility = true;
}
}
Instanciate the VM in the Main's View code behind:
public partial class MainWindow : Window
{
private readonly MainVM myMainVM;
public MainWindow()
{
InitializeComponent();
myMainVM = new MainVM();
DataContext = myMainVM;
}
}
Related
I'm new in c# but i try to have several small view that i had to one big view
but my databinding doesn't work.
I have use mvvm light.
I have add a datacontex in each small view.`
it is the code of the mainviewwindows:
<Window xmlns:View1="clr-namespace:BBS.CaseDetails.Operator.View" xmlns:View="clr-namespace:BBS.CaseDetails.Suspect.View" x:Class="BBS.CaseDetails.CaseDetailsWindow"
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:BBS.CaseDetails"
xmlns:diag="clr-namespace:System.Diagnostics;assembly=WindowsBase"
mc:Ignorable="d"
Title="CaseDetailsWindow" Height="450" Width="800">
<Grid d:DataContext="{Binding Source={StaticResource Locator}}">
<View1:CaseInformationView />
</Grid>
</Window>
the code of a small view :
<UserControl x:Class="BBS.CaseDetails.Operator.View.CaseInformationView"
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:BBS.CaseDetails.Operator.View"
xmlns:resx="clr-namespace:BBS.Resource.Properties;assembly=BBS.Resource"
mc:Ignorable="d"
d:DataContext="{Binding CaseInformationViewModel, Source={StaticResource Locator}}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1.5*" />
<ColumnDefinition Width="4*" />
</Grid.ColumnDefinitions>
<Label Grid.Row="0" Grid.Column="0" Content="{x:Static resx:CaseDetails.CaseInformation}" FontWeight="Bold"/>
<Label Grid.Row="1" Grid.Column="0" Content="{x:Static resx:CaseDetails.SteriaFitPlusOperator}"/>
<Label Grid.Row="2" Grid.Column="0" Content="{x:Static resx:CaseDetails.IncidentNumber}"/>
<Label Grid.Row="3" Grid.Column="0" Content="{x:Static resx:CaseDetails.IncidentDate}"/>
<TextBox Grid.Column="1" Grid.Row="1" Text="{Binding SteriaFitPlusOperator}" />
<TextBox Grid.Column="1" Grid.Row="2" Text="{Binding CaseInformationModel.IncidentNumber}" />
<DatePicker Grid.Column="1" Grid.Row="3" Text="{Binding CaseInformationModel.IncidentDate.Date, Mode=OneWay}" />
<Image Grid.Column="2" HorizontalAlignment="Center" Height="auto" Grid.Row="1" Width="100" />
</Grid>
</UserControl>
my viewmodel of my small view :
namespace BBS.CaseDetails.Operator.ViewModel
{
public class CaseInformationViewModel: ViewModelBase
{
private CaseInformationModel _caseInformationModel;
public CaseInformationModel CaseInformationModel
{
get
{
return _caseInformationModel;
}
set
{
Set(() => this.CaseInformationModel, ref _caseInformationModel, value);
}
}
}
}
Your problem might be here:
...<Grid d:DataContext="{Binding Source={StaticResource Locator}}">...
...mc:Ignorable="d"
d:DataContext="{Binding CaseInformationViewModel, Source={StaticResource Locator}}">...
Check this out: Commenting properties in xaml
I have a WPF application that I try to code using MVVM.The goal is to make something like a notification center, that lists different types of data.
To do this, I want to fill a ListView on the main page with different ViewModels. One ViewModel for each type of data.
The problem is:
When I put a (not a list) ViewModel in my ListView, it works fine. But if I put a list in my ListView, the program crashes on startup. I need the ListView to take a list (ObservableCollection perhaps) of mixed ViewModels.
I receive the error “Items collection must be empty before using ItemsSource.” at a seemingly random location in my code. Completely removing the code where the exception appears just causes it to show somewhere else.
I have the following:
C#:
public class MainViewModel : ObservableObject
{
private List<IPageViewModel> _items;
public MainViewModel()
{
_items = new List<IPageViewModel>
{
new StatusViewModel(),
new SettingsViewModel(),
new OverviewViewModel()
};
}
public List<IPageViewModel> Items => _items ?? (_items = newList<IPageViewModel>());
}
XAML:
<Window x:Class="InfoCenter.Views.Main.MainView"
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:test="clr-namespace:InfoCenter.Views.Test"
xmlns:main="clr-namespace:InfoCenter.Views.Main"
xmlns:views="clr-namespace:InfoCenter.Views"
xmlns:settings="clr-namespace:InfoCenter.Views.Settings"
xmlns:status="clr-namespace:InfoCenter.Views.Status"
xmlns:overview="clr-namespace:InfoCenter.Views.Overview"
mc:Ignorable="d"
Title="MainView" Height="450" Width="500"
MaxWidth="1920"
WindowStyle="None" Loaded="MainViewLoaded"
SizeChanged="MainViewSizeChanged"
PreviewKeyDown="OnPreviewKeyDown"
GotFocus="OnGotFocus"
Closing="OnClosing"
ResizeMode="NoResize"
d:DataContext="{d:DesignInstance main:MainViewModel}">
<Window.Resources>
<DataTemplate DataType="{x:Type overview:OverviewViewModel}">
<overview:OverviewView />
</DataTemplate>
<DataTemplate DataType="{x:Type status:StatusViewModel}">
<status:StatusView />
</DataTemplate>
<DataTemplate DataType="{x:Type settings:SettingsViewModel}">
<settings:SettingsView />
</DataTemplate>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="24" />
<RowDefinition Height="*" />
<RowDefinition Height="30" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="24" />
</Grid.ColumnDefinitions>
<Button Command="{Binding ButtonClickCommand}" CommandParameter="Minimize" Grid.Row="0" Grid.Column="1">
<Image Source="/Resources/arrow-down-1.png"></Image>
</Button>
<ListView ItemsSource="{Binding Items}" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2" ScrollViewer.HorizontalScrollBarVisibility="Hidden" PreviewMouseWheel="OnPreviewMouseWheel" ScrollViewer.VerticalScrollBarVisibility="Hidden">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="30" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Label Grid.Row="0" Grid.Column="0" Content="{Binding Path=Items.Header}" />
<ContentControl Grid.Row="1" Grid.Column="0" Content="{Binding}" />
</Grid>
</ListView>
<StatusBar FlowDirection="RightToLeft" Grid.Row="2" Grid.Column="0" Grid.ColumnSpan="2">
<Image Width="24" Height="24" Source="{Binding ConnectionIcon}" />
</StatusBar>
</Grid>
</Window>
I really hope that you can help. I have been trying to fix it the whole day!
You have put one thing in the ListView contents here: A Grid control. Don't do that. There are two ways to populate a ListView in XAML: Bind ItemsSource or put items inside the content of the ListView element. You can't do both, and you did both, so it threw an exception.
Here's the ItemsSource version.
<ListView
ItemsSource="{Binding Items}"
Grid.Row="1"
Grid.Column="0"
Grid.ColumnSpan="2"
ScrollViewer.HorizontalScrollBarVisibility="Hidden"
PreviewMouseWheel="OnPreviewMouseWheel"
ScrollViewer.VerticalScrollBarVisibility="Hidden"
/>
I'm not certain what that Grid is for; you may have to find somewhere else to put it.
But my guess is that want it to be used to display the items. We can do that by making it into an ItemTemplate. I'm a little confused by it, though: What is Items.Header? Items is a List, which has no Header property. Does IPageViewModel have a Header property? For the moment I'll assume that's the case; let me know if I'm mistaken.
<ListView
ItemsSource="{Binding Items}"
Grid.Row="1"
Grid.Column="0"
Grid.ColumnSpan="2"
ScrollViewer.HorizontalScrollBarVisibility="Hidden"
PreviewMouseWheel="OnPreviewMouseWheel"
ScrollViewer.VerticalScrollBarVisibility="Hidden"
>
<ListView.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="30" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Label
Grid.Row="0"
Grid.Column="0"
Content="{Binding Header}"
/>
<ContentControl
Grid.Row="1"
Grid.Column="0"
Content="{Binding}"
/>
</Grid>
<DataTemplate>
</ListView.ItemTemplate>
</ListView>
Based on the error I would recommend to change your XAML as was mentioned earlier in "Items collection must be empty before using ItemsSource."
Try this XAML:
<ListView ItemsSource="{Binding Items}" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2" ScrollViewer.HorizontalScrollBarVisibility="Hidden" PreviewMouseWheel="OnPreviewMouseWheel" ScrollViewer.VerticalScrollBarVisibility="Hidden">
<ListView.View>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="30" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Label Grid.Row="0" Grid.Column="0" Content="{Binding Path=Items.Header}" />
<ContentControl Grid.Row="1" Grid.Column="0" Content="{Binding}" />
</Grid>
</ListView.View>
</ListView>
Hope it will be helpful!
I'm developing UI for an application using WPF. I'm using command binding. Command works correctly when the button is put inside the Window. But when I put the button inside my UserControl the command parameter is null.
ViewModel code:
public RelayCommand<Window> MainCommand { get; private set; }
private void MainAction(Window window)
{
// here the parameter is null
if (window == null) return;
MainPage main = new MainPage();
main.Show();
window.Close();
}
The user control:
<UserControl x:Class="Kitchen.UI.View.HeaderFooter"
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:Kitchen.UI.View"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300">
<UserControl.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="../Skins/MainSkin.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</UserControl.Resources>
<UserControl.Template>
<ControlTemplate TargetType="UserControl">
<Grid DataContext="{Binding DataContext, RelativeSource={RelativeSource TemplatedParent}}">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"></RowDefinition>
<RowDefinition Height="*"></RowDefinition>
<RowDefinition Height="Auto"></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"></ColumnDefinition>
<ColumnDefinition Width="Auto"></ColumnDefinition>
<ColumnDefinition Width="*"></ColumnDefinition>
</Grid.ColumnDefinitions>
<ScrollViewer Grid.Column="1" Grid.Row="1" HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto">
<ContentControl Content="{TemplateBinding Content}"/>
</ScrollViewer>
<Image Grid.Column="0" Grid.Row="0" Grid.ColumnSpan="3" Source="{StaticResource HeaderImage}"
Margin="0 10 0 0" HorizontalAlignment="Stretch" SizeChanged="Image_SizeChanged" IsHitTestVisible="False"></Image>
<Image Grid.Column="0" Grid.Row="3" Grid.ColumnSpan="3" Source="{StaticResource FooterImage}"
Margin="0 -1 0 10" HorizontalAlignment="Stretch" Height="Auto"></Image>
</Grid>
</ControlTemplate>
</UserControl.Template>
</UserControl>
The way I put the button inside the user control:
<Window xmlns:View="clr-namespace:Kitchen.UI.View" x:Class="Kitchen.UI.View.Order" Name="OWindow" ResizeMode="NoResize" WindowState="Maximized"
WindowStartupLocation="CenterOwner" WindowStyle="None "
Width="1600"
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:ignore="http://www.galasoft.ch/ignore"
mc:Ignorable="d ignore"
DataContext="{Binding Order, Source={StaticResource Locator}}">
<View:HeaderFooter x:Name="HeaderFooter">
<Button Grid.Row="1" Grid.Column="0"
Command="{Binding ShowExitCommand}"
CommandParameter="{Binding ElementName=OWindow}"
Style="{StaticResource ImageButtonStyle}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition ></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Image Grid.Column="0" Grid.Row="0" Source="{StaticResource ButtonBack}" Width="180" Grid.ColumnSpan="2" />
<TextBlock Grid.Column="1" Grid.Row="0" Text="مشاهده سفارشات خارج شده از صف" Style="{StaticResource ImageButtonTextBlockStyle}" FontSize="15"/>
</Grid>
</Button>
</View:HeaderFooter>
</Window>
Try with x:Reference instead of ElementName, this should bring language-level support for element reference resolution, which ElementName (that operates at the framework level) may not be able to resolve.
CommandParameter="{Binding Source={x:Reference OWindow}}"
To avoid a cyclic dependency, you have to reference something that is not the container of the user control itself, for example
<Grid >
<DataGrid Name="OWindow" Width="10" Height="10"/>
<local:HeaderFooter x:Name="HeaderFooter">
<Button Grid.Row="1" Grid.Column="0"
Command="{Binding ShowExitCommand}"
CommandParameter="{Binding Source={x:Reference OWindow} }"
> <!-- instead of ElementName=OWindow -->
Please note, the above example makes clear that my answer correctly resolves the issue in a consistent context, while the circular reference is just another issue of the original code to be fixed.
Finally I changed my way through the problem. I needed a template to be applied to several windows, so I used a UserControl and it was successful as a template unless I wanted to pass the reference of the containing window of the UserControl as a parameter to a command from within the content of the UserControl.
Now I'm applying a custom ControlTemplate to the Window and it's working now.
But I think this is a bug or at least an architectural weakness for WPF. When you use {Binding ElementName=OWindow} from within the Window itself or other Controls like Grid the reference is resolved and handled but if you use it inside the user defined user control it causes the null reference.
I think this is because they are capturing the parameter at the Window construction.
I have a scenario that i am having four user controls in a window(like address, Skills, Personal info and General info each user control is having their own controls like textbox labels etc....) each user control having their own View Model
ex: General Info Control having A combo box which has list of persons and a text box Age, and text box Gender
Address is having 3 text boxes Street, Area, City
Skills control having 2 Text boxes Soft Skills and Tech Skills
so when user selects a particular person from the combo box then it has to update all the user controls with that particular person data
Main Window
<Window x:Class="CTSWpfApplication.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:View="clr-namespace:CTSWpfApplication.View"
xmlns:localViewModel="clr-namespace:CTSWpfApplication.ViewModel"
Title="MainWindow" Height="600" Width="1000">
<Window.Resources>
<DataTemplate DataType="{x:Type localViewModel:PersonViewModel}">
<View:PersonVorw/>
</DataTemplate>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="20*"/>
<RowDefinition Height="20*"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
</Grid.ColumnDefinitions>
<View:PersonVorw Grid.Row="0" Grid.Column="0" DataContext="{Binding PersonViewModel}"/>
<View:AddressView Grid.Row="0" Grid.Column="1"/>
<View:SkillsView Grid.Row="1" Grid.Column="0"/>
<View:PersonalInfoView Grid.Row="1" Grid.Column="1"/>
</Grid>
User Control PersonGeneralInfo(View)
<UserControl x:Class="CTSWpfApplication.View.PersonVorw"
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:i="http://schemas.microsoft.com/expression/2010/interactivity"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="500">
<Grid DataContext="{Binding PersonGenModel}">
<Grid.RowDefinitions>
<RowDefinition Height="40*"/>
<RowDefinition Height="20*"/>
<RowDefinition Height="20*"/>
<RowDefinition Height="20*"/>
<RowDefinition Height="20*"/>
<RowDefinition Height="20*"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="30*"/>
<ColumnDefinition Width="20*"/>
</Grid.ColumnDefinitions>
<ComboBox Height="25" Width="150" Grid.Column="1" Name="NameSelection" ItemsSource="{Binding ListFirstName}" SelectedValuePath="Key" DisplayMemberPath="Value" SelectedItem="{Binding MySelectedItem}">
</ComboBox>
<Label Height="25" Width="100" Content="First Name" Grid.Row="1" Grid.Column="0" />
<Label Height="25" Width="100" Content="Middle Name" Grid.Row="1" Grid.Column="1"/>
<Label Height="25" Width="100" Content="Last Name" Grid.Row="1" Grid.Column="2"/>
<TextBox Height="25" Width="120" Grid.Column="0" Grid.Row="2" Name="TxTFirstName" Text="{Binding FirstName}"/>
<TextBox Height="25" Width="120" Grid.Column="1" Grid.Row="2" Name="TxTMiddleName" Text="{Binding MiddleName}"/>
<TextBox Height="25" Width="120" Grid.Column="2" Grid.Row="2" Name="TxTLastName" Text="{Binding LastName}"/>
<Label Height="25" Width="100" Content="Age" Grid.Row="3" Grid.Column="0"/>
<Label Height="25" Width="100" Content="Gender" Grid.Row="4" Grid.Column="0"/>
<TextBox Height="25" Width="120" Grid.Column="1" Grid.Row="3" Name="TxTAge" Text="{Binding Age}"/>
<TextBox Height="25" Width="120" Grid.Column="1" Grid.Row="4" Name="TxTGender" Text="{Binding Gender}"/>
<Button Name="BtNPerson" Height="25" Width="100" Content="Clenter code hereick to Add" Grid.Row="5" Grid.Column="2" />
</Grid>
can any one Help me on to achieve this in the best way
Please excuse me if you fine any mistakes in my post
thanks in advance
You will have to notify other ViewModels when change occurs. This article explains the patterns that can be followed to achieve the result.
You can set up a MainViewModel that creates your other ViewModels.
Create a property in each of you ViewModels called SelectedComboBoxItem.
Bind your ComboBox's SelectedItem in the MainViewModel to a command that sets
the SelectedComboBoxItem of each of the other ViewModels.
To be honest I don't know if it will work, but make sure to have INotifyPropertyChanged implemented in all of the ViewModels and their properties.
Example:
public class MainViewModel : ViewModelBase
{
private YourInfoItem _selectedComboBoxItem;
private ViewModel1 SkillsInfoVM = new ViewModel1();
private ViewModel2 PersonalInfoVM = new ViewModel2();
private ViewModel3 GeneralInfoVM = new ViewModel3();
public YourInfoItem selectedComboBoxItem
{
get {return _selectedComboBoxItem; }
set
{
_selectedComboBoxItem = value;
PropertyChanged(nameof(selectedComboBoxItem));
}
}
public MainViewModel()
{
SelectedComboBoxItemChanged = new RelayCommand(SetSelectedComboBoxItem);
}
public ICommand SelectedComboBoxItemChanged { get; private set; }
public void SetSelectedComboBoxItem()
{
SkillsInfoVM.selectedComboBoxItem = this.selectedComboBoxItem;
PersonalInfoVM.selectedComboBoxItem = this.selectedComboBoxItem;
GeneralInfoVM.selectedComboBoxItem = this.selectedComboBoxItem;
}
}
In the end you just bind the SelectedComboBoxItem to your TextBoxes in the XAML code e.g:
<TextBox Text="{Binding SelectedComboBoxItem.FirstName, UpdateSourceTrigger=OnPropertyChanged, Mode=TwoWay}"/>
and so on.
This does require you to have an object that contains all the information you want to show, you can do that by creating a class containing all the info, similar to this:
public class Info
{
public string FirstName;
public string LastName;
public string Address;
...
}
This is my code to open childwindow:
ImageLocation location = new ImageLocation();
location.WindowStartupLocation = Xceed.Wpf.Toolkit.WindowStartupLocation.Center;
location.Show();
But the childwindow doesn't show at all.
This is my xaml for childwindow:
<xctk:ChildWindow x:Class="CXLocalSearch.Dialogs.ImageLocation"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Caption="Image Path"
xmlns:xctk="http://schemas.xceed.com/wpf/xaml/toolkit"
Height="64" Width="400">
<Grid x:Name="LayoutRoot">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" MinWidth="63.95"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition/>
</Grid.RowDefinitions>
<TextBlock Margin="2" TextWrapping="Wrap" Text="Image Path" VerticalAlignment="Center" HorizontalAlignment="Left"/>
<StackPanel Grid.Column="1" HorizontalAlignment="Left" Margin="3,2,0,2" Orientation="Horizontal" >
<TextBox x:Name="txtPath" Margin="0,2" TextWrapping="Wrap" VerticalAlignment="Center" Width="250"/>
<Button x:Name="btnSave" Content="Save" Click="btnSave_Click" Width="60" Margin="3,0,0,0"/>
</StackPanel>
</Grid>
</xctk:ChildWindow>
Could anybody please clarify what the issue is?
From the looks of it, you've separated your ChildWindow into a separate control. That's fine, but it needs to be hosted inside a primary window in order to ever become visible. Start with the simplest thing possible:
<Window>
<Grid>
<Button Click="...">Click to Show</Button>
<xctk:ChildWindow x:Name="childWindow">
<TextBlock>Hello!</TextBlock>
</xctk:ChildWindow>
</Grid>
</Window>
I think you'll find this works fine (assumes event hookup), so take it from there.