在WPF的画布上添加/删除用户控件
我创建了两个WPF用户控件，它们有多个文本框、组合框和按钮。在主wpf窗口中，我创建了一个画布和一个列表框，其中包含两个listitems。我的要求是，如果选择第一个listbox项，那么第一个用户控件应该添加到画布中。如果选择第二个listbox项，则先前添加的用户控件应该隐藏，第二个控件应该添加/显示。有人能为这段代码提供一个示例吗 下面是我编写的代码。我创建了两个用户控件 UserControl1.xaml在WPF的画布上添加/删除用户控件,wpf,canvas,user-controls,Wpf,Canvas,User Controls,我创建了两个WPF用户控件，它们有多个文本框、组合框和按钮。在主wpf窗口中，我创建了一个画布和一个列表框，其中包含两个listitems。我的要求是，如果选择第一个listbox项，那么第一个用户控件应该添加到画布中。如果选择第二个listbox项，则先前添加的用户控件应该隐藏，第二个控件应该添加/显示。有人能为这段代码提供一个示例吗 下面是我编写的代码。我创建了两个用户控件 UserControl1.xaml <UserControl x:Class="UserControl1
<UserControl x:Class="UserControl1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Width="210" Height="210" x:Name="UCntl1">
<Grid>
<StackPanel>
<GroupBox Header="Text Boxes">
<StackPanel Orientation="Horizontal">
<StackPanel>
<Label Margin="4" Height="21">TextBox1</Label>
<Label Margin="4" Height="21">TextBox2</Label>
<Label Margin="4" Height="21">TextBox3</Label>
</StackPanel>
<StackPanel>
<TextBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4">0.1</TextBox>
<TextBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4">0.2</TextBox>
<TextBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4">0.3</TextBox>
</StackPanel>
</StackPanel>
</GroupBox>
<GroupBox Header="Conbo Boxes">
<StackPanel Orientation="Horizontal">
<StackPanel>
<Label Margin="4" Height="21">ComboBox1</Label>
<Label Margin="4" Height="21">ComboBox2</Label>
<Label Margin="4" Height="21">ComboBox3</Label>
</StackPanel>
<StackPanel>
<ComboBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4">
<ComboBoxItem>Item AAA</ComboBoxItem>
</ComboBox>
<ComboBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4">
<ComboBoxItem>Item BBB</ComboBoxItem>
</ComboBox>
<ComboBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4">
<ComboBoxItem>Item CCC</ComboBoxItem>
</ComboBox>
</StackPanel>
</StackPanel>
</GroupBox>
</StackPanel>
</Grid>
</UserControl>
<UserControl x:Class="UserControl2"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Width="210" Height="210" x:Name="UCntl2">
<Grid>
<StackPanel>
<GroupBox Header="Conbo Boxes">
<StackPanel Orientation="Horizontal">
<StackPanel>
<Label Margin="4" Height="21">ComboBox1</Label>
<Label Margin="4" Height="21">ComboBox2</Label>
<Label Margin="4" Height="21">ComboBox3</Label>
</StackPanel>
<StackPanel>
<ComboBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4"></ComboBox>
<ComboBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4"></ComboBox>
<ComboBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4"></ComboBox>
</StackPanel>
</StackPanel>
</GroupBox>
<GroupBox Header="Text Boxes">
<StackPanel Orientation="Horizontal">
<StackPanel>
<Label Margin="4" Height="21">TextBox1</Label>
<Label Margin="4" Height="21">TextBox2</Label>
<Label Margin="4" Height="21">TextBox3</Label>
</StackPanel>
<StackPanel>
<TextBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4"></TextBox>
<TextBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4"></TextBox>
<TextBox Width="100" Height="21" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="4"></TextBox>
</StackPanel>
</StackPanel>
</GroupBox>
</StackPanel>
</Grid>
<Window x:Class="Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" Height="Auto" Width="Auto">
<Grid>
<StackPanel Orientation="Horizontal">
<Grid Margin="0,0,0,0" Width="Auto" Height="Auto" VerticalAlignment="Top">
<ListBox Margin="0,0,0,0" HorizontalAlignment="Left" Width="Auto" Height="Auto" VerticalAlignment="Top" BorderBrush="White">
<ListBoxItem Name="LstItem1" Selected="LstItem1_Selected">User Control 1</ListBoxItem>
<ListBoxItem Name="LstItem2" Selected="LstItem2_Selected">User Control 2</ListBoxItem>
</ListBox>
</Grid>
<Grid Width="10" Background="LightGray"></Grid>
<Grid Margin="0,0,0,0">
<Canvas Name="Canvas1" Width="210" Height="210" VerticalAlignment="Top">
</Canvas>
</Grid>
</StackPanel>
</Grid>
在删除画布中以前的控件后，我添加了用户控件。因此，在将控件重新添加到画布时，UserControls列表框中的选定值将被清除。是否有任何方法可以在画布上隐藏用户控件，而不是从画布上删除控件。这应该可以让您开始。这不完全是我在真实项目中的做法，但已经足够接近了。我希望有一个简单的方式来附加项目的答案在这个网站上 最终结果如下所示： App.xaml：
<Application x:Class="SO9735486.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="clr-namespace:SO9735486.ViewModels"
xmlns:v="clr-namespace:SO9735486.Views"
StartupUri="MainWindow.xaml">
<Application.Resources>
<DataTemplate DataType="{x:Type vm:MainViewModel}">
<v:MainView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:FirstContentViewModel}">
<v:FirstContentView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:SecondContentViewModel}">
<v:SecondContentView/>
</DataTemplate>
</Application.Resources>
</Application>
<Window x:Class="SO9735486.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow">
</Window>
namespace SO9735486
{
using System.Windows;
using SO9735486.ViewModels;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.Content = new MainViewModel();
}
}
}
namespace SO9735486.ViewModels
{
using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Threading;
// http://kentb.blogspot.com/2009/04/mvvm-infrastructure-viewmodel.html
public abstract class ViewModel : INotifyPropertyChanged
{
private readonly Dispatcher _dispatcher;
protected ViewModel()
{
if (Application.Current != null)
{
_dispatcher = Application.Current.Dispatcher;
}
else
{
//this is useful for unit tests where there is no application running
_dispatcher = Dispatcher.CurrentDispatcher;
}
}
[field: NonSerialized]
public event PropertyChangedEventHandler PropertyChanged;
protected Dispatcher Dispatcher
{
get { return _dispatcher; }
}
protected virtual void OnPropertyChanged(PropertyChangedEventArgs e)
{
var handler = this.PropertyChanged;
if (handler != null)
{
handler(this, e);
}
}
protected void OnPropertyChanged(string propertyName)
{
OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
}
}
}
namespace SO9735486.ViewModels
{
public abstract class ContentViewModel : ViewModel
{
private readonly string displayName;
protected ContentViewModel(string displayName)
{
this.displayName = displayName;
}
public string DisplayName
{
get { return this.displayName; }
}
}
}
namespace SO9735486.ViewModels
{
public sealed class FirstContentViewModel : ContentViewModel
{
private string name;
public FirstContentViewModel()
: base("First")
{
}
public string Name
{
get { return this.name; }
set
{
if (this.name != value)
{
this.name = value;
this.OnPropertyChanged("Name");
}
}
}
}
}
namespace SO9735486.ViewModels
{
public sealed class SecondContentViewModel : ContentViewModel
{
public SecondContentViewModel()
: base("Second")
{
}
}
}
namespace SO9735486.ViewModels
{
using System.Collections.Generic;
using System.Linq;
public sealed class MainViewModel : ViewModel
{
private readonly ICollection<ContentViewModel> contentViewModels;
private ContentViewModel selectedContentViewModel;
public MainViewModel()
{
this.contentViewModels = new List<ContentViewModel>
{
new FirstContentViewModel(),
new SecondContentViewModel()
};
this.selectedContentViewModel = this.contentViewModels.First();
}
public ICollection<ContentViewModel> ContentViewModels
{
get { return this.contentViewModels; }
}
public ContentViewModel SelectedContentViewModel
{
get { return this.selectedContentViewModel; }
set
{
if (this.selectedContentViewModel != value)
{
this.selectedContentViewModel = value;
this.OnPropertyChanged("SelectedContentViewModel");
}
}
}
}
}
<UserControl x:Class="SO9735486.Views.FirstContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>First Content View</Label>
<TextBox Text="{Binding Name}"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.SecondContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>Second content view</Label>
<Rectangle Fill="Blue" Width="100" Height="30"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<DockPanel>
<ComboBox DockPanel.Dock="Top" ItemsSource="{Binding ContentViewModels}" SelectedItem="{Binding SelectedContentViewModel}" DisplayMemberPath="DisplayName"/>
<ContentControl Content="{Binding SelectedContentViewModel}"/>
</DockPanel>
</UserControl>
<Application x:Class="SO9735486.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="clr-namespace:SO9735486.ViewModels"
xmlns:v="clr-namespace:SO9735486.Views"
StartupUri="MainWindow.xaml">
<Application.Resources>
<DataTemplate DataType="{x:Type vm:MainViewModel}">
<v:MainView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:FirstContentViewModel}">
<v:FirstContentView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:SecondContentViewModel}">
<v:SecondContentView/>
</DataTemplate>
</Application.Resources>
</Application>
<Window x:Class="SO9735486.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow">
</Window>
namespace SO9735486
{
using System.Windows;
using SO9735486.ViewModels;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.Content = new MainViewModel();
}
}
}
namespace SO9735486.ViewModels
{
using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Threading;
// http://kentb.blogspot.com/2009/04/mvvm-infrastructure-viewmodel.html
public abstract class ViewModel : INotifyPropertyChanged
{
private readonly Dispatcher _dispatcher;
protected ViewModel()
{
if (Application.Current != null)
{
_dispatcher = Application.Current.Dispatcher;
}
else
{
//this is useful for unit tests where there is no application running
_dispatcher = Dispatcher.CurrentDispatcher;
}
}
[field: NonSerialized]
public event PropertyChangedEventHandler PropertyChanged;
protected Dispatcher Dispatcher
{
get { return _dispatcher; }
}
protected virtual void OnPropertyChanged(PropertyChangedEventArgs e)
{
var handler = this.PropertyChanged;
if (handler != null)
{
handler(this, e);
}
}
protected void OnPropertyChanged(string propertyName)
{
OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
}
}
}
namespace SO9735486.ViewModels
{
public abstract class ContentViewModel : ViewModel
{
private readonly string displayName;
protected ContentViewModel(string displayName)
{
this.displayName = displayName;
}
public string DisplayName
{
get { return this.displayName; }
}
}
}
namespace SO9735486.ViewModels
{
public sealed class FirstContentViewModel : ContentViewModel
{
private string name;
public FirstContentViewModel()
: base("First")
{
}
public string Name
{
get { return this.name; }
set
{
if (this.name != value)
{
this.name = value;
this.OnPropertyChanged("Name");
}
}
}
}
}
namespace SO9735486.ViewModels
{
public sealed class SecondContentViewModel : ContentViewModel
{
public SecondContentViewModel()
: base("Second")
{
}
}
}
namespace SO9735486.ViewModels
{
using System.Collections.Generic;
using System.Linq;
public sealed class MainViewModel : ViewModel
{
private readonly ICollection<ContentViewModel> contentViewModels;
private ContentViewModel selectedContentViewModel;
public MainViewModel()
{
this.contentViewModels = new List<ContentViewModel>
{
new FirstContentViewModel(),
new SecondContentViewModel()
};
this.selectedContentViewModel = this.contentViewModels.First();
}
public ICollection<ContentViewModel> ContentViewModels
{
get { return this.contentViewModels; }
}
public ContentViewModel SelectedContentViewModel
{
get { return this.selectedContentViewModel; }
set
{
if (this.selectedContentViewModel != value)
{
this.selectedContentViewModel = value;
this.OnPropertyChanged("SelectedContentViewModel");
}
}
}
}
}
<UserControl x:Class="SO9735486.Views.FirstContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>First Content View</Label>
<TextBox Text="{Binding Name}"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.SecondContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>Second content view</Label>
<Rectangle Fill="Blue" Width="100" Height="30"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<DockPanel>
<ComboBox DockPanel.Dock="Top" ItemsSource="{Binding ContentViewModels}" SelectedItem="{Binding SelectedContentViewModel}" DisplayMemberPath="DisplayName"/>
<ContentControl Content="{Binding SelectedContentViewModel}"/>
</DockPanel>
</UserControl>
<Application x:Class="SO9735486.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="clr-namespace:SO9735486.ViewModels"
xmlns:v="clr-namespace:SO9735486.Views"
StartupUri="MainWindow.xaml">
<Application.Resources>
<DataTemplate DataType="{x:Type vm:MainViewModel}">
<v:MainView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:FirstContentViewModel}">
<v:FirstContentView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:SecondContentViewModel}">
<v:SecondContentView/>
</DataTemplate>
</Application.Resources>
</Application>
<Window x:Class="SO9735486.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow">
</Window>
namespace SO9735486
{
using System.Windows;
using SO9735486.ViewModels;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.Content = new MainViewModel();
}
}
}
namespace SO9735486.ViewModels
{
using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Threading;
// http://kentb.blogspot.com/2009/04/mvvm-infrastructure-viewmodel.html
public abstract class ViewModel : INotifyPropertyChanged
{
private readonly Dispatcher _dispatcher;
protected ViewModel()
{
if (Application.Current != null)
{
_dispatcher = Application.Current.Dispatcher;
}
else
{
//this is useful for unit tests where there is no application running
_dispatcher = Dispatcher.CurrentDispatcher;
}
}
[field: NonSerialized]
public event PropertyChangedEventHandler PropertyChanged;
protected Dispatcher Dispatcher
{
get { return _dispatcher; }
}
protected virtual void OnPropertyChanged(PropertyChangedEventArgs e)
{
var handler = this.PropertyChanged;
if (handler != null)
{
handler(this, e);
}
}
protected void OnPropertyChanged(string propertyName)
{
OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
}
}
}
namespace SO9735486.ViewModels
{
public abstract class ContentViewModel : ViewModel
{
private readonly string displayName;
protected ContentViewModel(string displayName)
{
this.displayName = displayName;
}
public string DisplayName
{
get { return this.displayName; }
}
}
}
namespace SO9735486.ViewModels
{
public sealed class FirstContentViewModel : ContentViewModel
{
private string name;
public FirstContentViewModel()
: base("First")
{
}
public string Name
{
get { return this.name; }
set
{
if (this.name != value)
{
this.name = value;
this.OnPropertyChanged("Name");
}
}
}
}
}
namespace SO9735486.ViewModels
{
public sealed class SecondContentViewModel : ContentViewModel
{
public SecondContentViewModel()
: base("Second")
{
}
}
}
namespace SO9735486.ViewModels
{
using System.Collections.Generic;
using System.Linq;
public sealed class MainViewModel : ViewModel
{
private readonly ICollection<ContentViewModel> contentViewModels;
private ContentViewModel selectedContentViewModel;
public MainViewModel()
{
this.contentViewModels = new List<ContentViewModel>
{
new FirstContentViewModel(),
new SecondContentViewModel()
};
this.selectedContentViewModel = this.contentViewModels.First();
}
public ICollection<ContentViewModel> ContentViewModels
{
get { return this.contentViewModels; }
}
public ContentViewModel SelectedContentViewModel
{
get { return this.selectedContentViewModel; }
set
{
if (this.selectedContentViewModel != value)
{
this.selectedContentViewModel = value;
this.OnPropertyChanged("SelectedContentViewModel");
}
}
}
}
}
<UserControl x:Class="SO9735486.Views.FirstContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>First Content View</Label>
<TextBox Text="{Binding Name}"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.SecondContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>Second content view</Label>
<Rectangle Fill="Blue" Width="100" Height="30"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<DockPanel>
<ComboBox DockPanel.Dock="Top" ItemsSource="{Binding ContentViewModels}" SelectedItem="{Binding SelectedContentViewModel}" DisplayMemberPath="DisplayName"/>
<ContentControl Content="{Binding SelectedContentViewModel}"/>
</DockPanel>
</UserControl>
<Application x:Class="SO9735486.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="clr-namespace:SO9735486.ViewModels"
xmlns:v="clr-namespace:SO9735486.Views"
StartupUri="MainWindow.xaml">
<Application.Resources>
<DataTemplate DataType="{x:Type vm:MainViewModel}">
<v:MainView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:FirstContentViewModel}">
<v:FirstContentView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:SecondContentViewModel}">
<v:SecondContentView/>
</DataTemplate>
</Application.Resources>
</Application>
<Window x:Class="SO9735486.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow">
</Window>
namespace SO9735486
{
using System.Windows;
using SO9735486.ViewModels;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.Content = new MainViewModel();
}
}
}
namespace SO9735486.ViewModels
{
using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Threading;
// http://kentb.blogspot.com/2009/04/mvvm-infrastructure-viewmodel.html
public abstract class ViewModel : INotifyPropertyChanged
{
private readonly Dispatcher _dispatcher;
protected ViewModel()
{
if (Application.Current != null)
{
_dispatcher = Application.Current.Dispatcher;
}
else
{
//this is useful for unit tests where there is no application running
_dispatcher = Dispatcher.CurrentDispatcher;
}
}
[field: NonSerialized]
public event PropertyChangedEventHandler PropertyChanged;
protected Dispatcher Dispatcher
{
get { return _dispatcher; }
}
protected virtual void OnPropertyChanged(PropertyChangedEventArgs e)
{
var handler = this.PropertyChanged;
if (handler != null)
{
handler(this, e);
}
}
protected void OnPropertyChanged(string propertyName)
{
OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
}
}
}
namespace SO9735486.ViewModels
{
public abstract class ContentViewModel : ViewModel
{
private readonly string displayName;
protected ContentViewModel(string displayName)
{
this.displayName = displayName;
}
public string DisplayName
{
get { return this.displayName; }
}
}
}
namespace SO9735486.ViewModels
{
public sealed class FirstContentViewModel : ContentViewModel
{
private string name;
public FirstContentViewModel()
: base("First")
{
}
public string Name
{
get { return this.name; }
set
{
if (this.name != value)
{
this.name = value;
this.OnPropertyChanged("Name");
}
}
}
}
}
namespace SO9735486.ViewModels
{
public sealed class SecondContentViewModel : ContentViewModel
{
public SecondContentViewModel()
: base("Second")
{
}
}
}
namespace SO9735486.ViewModels
{
using System.Collections.Generic;
using System.Linq;
public sealed class MainViewModel : ViewModel
{
private readonly ICollection<ContentViewModel> contentViewModels;
private ContentViewModel selectedContentViewModel;
public MainViewModel()
{
this.contentViewModels = new List<ContentViewModel>
{
new FirstContentViewModel(),
new SecondContentViewModel()
};
this.selectedContentViewModel = this.contentViewModels.First();
}
public ICollection<ContentViewModel> ContentViewModels
{
get { return this.contentViewModels; }
}
public ContentViewModel SelectedContentViewModel
{
get { return this.selectedContentViewModel; }
set
{
if (this.selectedContentViewModel != value)
{
this.selectedContentViewModel = value;
this.OnPropertyChanged("SelectedContentViewModel");
}
}
}
}
}
<UserControl x:Class="SO9735486.Views.FirstContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>First Content View</Label>
<TextBox Text="{Binding Name}"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.SecondContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>Second content view</Label>
<Rectangle Fill="Blue" Width="100" Height="30"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<DockPanel>
<ComboBox DockPanel.Dock="Top" ItemsSource="{Binding ContentViewModels}" SelectedItem="{Binding SelectedContentViewModel}" DisplayMemberPath="DisplayName"/>
<ContentControl Content="{Binding SelectedContentViewModel}"/>
</DockPanel>
</UserControl>
<Application x:Class="SO9735486.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="clr-namespace:SO9735486.ViewModels"
xmlns:v="clr-namespace:SO9735486.Views"
StartupUri="MainWindow.xaml">
<Application.Resources>
<DataTemplate DataType="{x:Type vm:MainViewModel}">
<v:MainView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:FirstContentViewModel}">
<v:FirstContentView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:SecondContentViewModel}">
<v:SecondContentView/>
</DataTemplate>
</Application.Resources>
</Application>
<Window x:Class="SO9735486.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow">
</Window>
namespace SO9735486
{
using System.Windows;
using SO9735486.ViewModels;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.Content = new MainViewModel();
}
}
}
namespace SO9735486.ViewModels
{
using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Threading;
// http://kentb.blogspot.com/2009/04/mvvm-infrastructure-viewmodel.html
public abstract class ViewModel : INotifyPropertyChanged
{
private readonly Dispatcher _dispatcher;
protected ViewModel()
{
if (Application.Current != null)
{
_dispatcher = Application.Current.Dispatcher;
}
else
{
//this is useful for unit tests where there is no application running
_dispatcher = Dispatcher.CurrentDispatcher;
}
}
[field: NonSerialized]
public event PropertyChangedEventHandler PropertyChanged;
protected Dispatcher Dispatcher
{
get { return _dispatcher; }
}
protected virtual void OnPropertyChanged(PropertyChangedEventArgs e)
{
var handler = this.PropertyChanged;
if (handler != null)
{
handler(this, e);
}
}
protected void OnPropertyChanged(string propertyName)
{
OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
}
}
}
namespace SO9735486.ViewModels
{
public abstract class ContentViewModel : ViewModel
{
private readonly string displayName;
protected ContentViewModel(string displayName)
{
this.displayName = displayName;
}
public string DisplayName
{
get { return this.displayName; }
}
}
}
namespace SO9735486.ViewModels
{
public sealed class FirstContentViewModel : ContentViewModel
{
private string name;
public FirstContentViewModel()
: base("First")
{
}
public string Name
{
get { return this.name; }
set
{
if (this.name != value)
{
this.name = value;
this.OnPropertyChanged("Name");
}
}
}
}
}
namespace SO9735486.ViewModels
{
public sealed class SecondContentViewModel : ContentViewModel
{
public SecondContentViewModel()
: base("Second")
{
}
}
}
namespace SO9735486.ViewModels
{
using System.Collections.Generic;
using System.Linq;
public sealed class MainViewModel : ViewModel
{
private readonly ICollection<ContentViewModel> contentViewModels;
private ContentViewModel selectedContentViewModel;
public MainViewModel()
{
this.contentViewModels = new List<ContentViewModel>
{
new FirstContentViewModel(),
new SecondContentViewModel()
};
this.selectedContentViewModel = this.contentViewModels.First();
}
public ICollection<ContentViewModel> ContentViewModels
{
get { return this.contentViewModels; }
}
public ContentViewModel SelectedContentViewModel
{
get { return this.selectedContentViewModel; }
set
{
if (this.selectedContentViewModel != value)
{
this.selectedContentViewModel = value;
this.OnPropertyChanged("SelectedContentViewModel");
}
}
}
}
}
<UserControl x:Class="SO9735486.Views.FirstContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>First Content View</Label>
<TextBox Text="{Binding Name}"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.SecondContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>Second content view</Label>
<Rectangle Fill="Blue" Width="100" Height="30"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<DockPanel>
<ComboBox DockPanel.Dock="Top" ItemsSource="{Binding ContentViewModels}" SelectedItem="{Binding SelectedContentViewModel}" DisplayMemberPath="DisplayName"/>
<ContentControl Content="{Binding SelectedContentViewModel}"/>
</DockPanel>
</UserControl>
<Application x:Class="SO9735486.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="clr-namespace:SO9735486.ViewModels"
xmlns:v="clr-namespace:SO9735486.Views"
StartupUri="MainWindow.xaml">
<Application.Resources>
<DataTemplate DataType="{x:Type vm:MainViewModel}">
<v:MainView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:FirstContentViewModel}">
<v:FirstContentView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:SecondContentViewModel}">
<v:SecondContentView/>
</DataTemplate>
</Application.Resources>
</Application>
<Window x:Class="SO9735486.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow">
</Window>
namespace SO9735486
{
using System.Windows;
using SO9735486.ViewModels;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.Content = new MainViewModel();
}
}
}
namespace SO9735486.ViewModels
{
using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Threading;
// http://kentb.blogspot.com/2009/04/mvvm-infrastructure-viewmodel.html
public abstract class ViewModel : INotifyPropertyChanged
{
private readonly Dispatcher _dispatcher;
protected ViewModel()
{
if (Application.Current != null)
{
_dispatcher = Application.Current.Dispatcher;
}
else
{
//this is useful for unit tests where there is no application running
_dispatcher = Dispatcher.CurrentDispatcher;
}
}
[field: NonSerialized]
public event PropertyChangedEventHandler PropertyChanged;
protected Dispatcher Dispatcher
{
get { return _dispatcher; }
}
protected virtual void OnPropertyChanged(PropertyChangedEventArgs e)
{
var handler = this.PropertyChanged;
if (handler != null)
{
handler(this, e);
}
}
protected void OnPropertyChanged(string propertyName)
{
OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
}
}
}
namespace SO9735486.ViewModels
{
public abstract class ContentViewModel : ViewModel
{
private readonly string displayName;
protected ContentViewModel(string displayName)
{
this.displayName = displayName;
}
public string DisplayName
{
get { return this.displayName; }
}
}
}
namespace SO9735486.ViewModels
{
public sealed class FirstContentViewModel : ContentViewModel
{
private string name;
public FirstContentViewModel()
: base("First")
{
}
public string Name
{
get { return this.name; }
set
{
if (this.name != value)
{
this.name = value;
this.OnPropertyChanged("Name");
}
}
}
}
}
namespace SO9735486.ViewModels
{
public sealed class SecondContentViewModel : ContentViewModel
{
public SecondContentViewModel()
: base("Second")
{
}
}
}
namespace SO9735486.ViewModels
{
using System.Collections.Generic;
using System.Linq;
public sealed class MainViewModel : ViewModel
{
private readonly ICollection<ContentViewModel> contentViewModels;
private ContentViewModel selectedContentViewModel;
public MainViewModel()
{
this.contentViewModels = new List<ContentViewModel>
{
new FirstContentViewModel(),
new SecondContentViewModel()
};
this.selectedContentViewModel = this.contentViewModels.First();
}
public ICollection<ContentViewModel> ContentViewModels
{
get { return this.contentViewModels; }
}
public ContentViewModel SelectedContentViewModel
{
get { return this.selectedContentViewModel; }
set
{
if (this.selectedContentViewModel != value)
{
this.selectedContentViewModel = value;
this.OnPropertyChanged("SelectedContentViewModel");
}
}
}
}
}
<UserControl x:Class="SO9735486.Views.FirstContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>First Content View</Label>
<TextBox Text="{Binding Name}"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.SecondContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>Second content view</Label>
<Rectangle Fill="Blue" Width="100" Height="30"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<DockPanel>
<ComboBox DockPanel.Dock="Top" ItemsSource="{Binding ContentViewModels}" SelectedItem="{Binding SelectedContentViewModel}" DisplayMemberPath="DisplayName"/>
<ContentControl Content="{Binding SelectedContentViewModel}"/>
</DockPanel>
</UserControl>
namespace SO9735486.ViewModels
{
使用System.Collections.Generic；
使用System.Linq；
公共密封类MainViewModel:ViewModel
{
私有只读ICollection contentViewModels；
私有ContentViewModel选择ContentViewModel；
公共主视图模型（）
{
this.contentViewModels=新列表
{
新的FirstContentViewModel（），
新的SecondContentViewModel（）
};
this.selectedContentViewModel=this.contentViewModels.First（）；
}
公共ICollection内容视图模型
{
获取{返回this.contentViewModels；}
}
公共内容视图模型已选择内容视图模型
{
获取{返回this.selectedContentViewModel；}
设置
{
if（this.selectedContentViewModel！=值）
{
this.selectedContentViewModel=值；
此.OnPropertyChanged（“SelectedContentViewModel”）；
}
}
}
}
}
<Application x:Class="SO9735486.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="clr-namespace:SO9735486.ViewModels"
xmlns:v="clr-namespace:SO9735486.Views"
StartupUri="MainWindow.xaml">
<Application.Resources>
<DataTemplate DataType="{x:Type vm:MainViewModel}">
<v:MainView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:FirstContentViewModel}">
<v:FirstContentView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:SecondContentViewModel}">
<v:SecondContentView/>
</DataTemplate>
</Application.Resources>
</Application>
<Window x:Class="SO9735486.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow">
</Window>
namespace SO9735486
{
using System.Windows;
using SO9735486.ViewModels;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.Content = new MainViewModel();
}
}
}
namespace SO9735486.ViewModels
{
using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Threading;
// http://kentb.blogspot.com/2009/04/mvvm-infrastructure-viewmodel.html
public abstract class ViewModel : INotifyPropertyChanged
{
private readonly Dispatcher _dispatcher;
protected ViewModel()
{
if (Application.Current != null)
{
_dispatcher = Application.Current.Dispatcher;
}
else
{
//this is useful for unit tests where there is no application running
_dispatcher = Dispatcher.CurrentDispatcher;
}
}
[field: NonSerialized]
public event PropertyChangedEventHandler PropertyChanged;
protected Dispatcher Dispatcher
{
get { return _dispatcher; }
}
protected virtual void OnPropertyChanged(PropertyChangedEventArgs e)
{
var handler = this.PropertyChanged;
if (handler != null)
{
handler(this, e);
}
}
protected void OnPropertyChanged(string propertyName)
{
OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
}
}
}
namespace SO9735486.ViewModels
{
public abstract class ContentViewModel : ViewModel
{
private readonly string displayName;
protected ContentViewModel(string displayName)
{
this.displayName = displayName;
}
public string DisplayName
{
get { return this.displayName; }
}
}
}
namespace SO9735486.ViewModels
{
public sealed class FirstContentViewModel : ContentViewModel
{
private string name;
public FirstContentViewModel()
: base("First")
{
}
public string Name
{
get { return this.name; }
set
{
if (this.name != value)
{
this.name = value;
this.OnPropertyChanged("Name");
}
}
}
}
}
namespace SO9735486.ViewModels
{
public sealed class SecondContentViewModel : ContentViewModel
{
public SecondContentViewModel()
: base("Second")
{
}
}
}
namespace SO9735486.ViewModels
{
using System.Collections.Generic;
using System.Linq;
public sealed class MainViewModel : ViewModel
{
private readonly ICollection<ContentViewModel> contentViewModels;
private ContentViewModel selectedContentViewModel;
public MainViewModel()
{
this.contentViewModels = new List<ContentViewModel>
{
new FirstContentViewModel(),
new SecondContentViewModel()
};
this.selectedContentViewModel = this.contentViewModels.First();
}
public ICollection<ContentViewModel> ContentViewModels
{
get { return this.contentViewModels; }
}
public ContentViewModel SelectedContentViewModel
{
get { return this.selectedContentViewModel; }
set
{
if (this.selectedContentViewModel != value)
{
this.selectedContentViewModel = value;
this.OnPropertyChanged("SelectedContentViewModel");
}
}
}
}
}
<UserControl x:Class="SO9735486.Views.FirstContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>First Content View</Label>
<TextBox Text="{Binding Name}"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.SecondContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>Second content view</Label>
<Rectangle Fill="Blue" Width="100" Height="30"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<DockPanel>
<ComboBox DockPanel.Dock="Top" ItemsSource="{Binding ContentViewModels}" SelectedItem="{Binding SelectedContentViewModel}" DisplayMemberPath="DisplayName"/>
<ContentControl Content="{Binding SelectedContentViewModel}"/>
</DockPanel>
</UserControl>
第一内容视图
<Application x:Class="SO9735486.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="clr-namespace:SO9735486.ViewModels"
xmlns:v="clr-namespace:SO9735486.Views"
StartupUri="MainWindow.xaml">
<Application.Resources>
<DataTemplate DataType="{x:Type vm:MainViewModel}">
<v:MainView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:FirstContentViewModel}">
<v:FirstContentView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:SecondContentViewModel}">
<v:SecondContentView/>
</DataTemplate>
</Application.Resources>
</Application>
<Window x:Class="SO9735486.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow">
</Window>
namespace SO9735486
{
using System.Windows;
using SO9735486.ViewModels;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.Content = new MainViewModel();
}
}
}
namespace SO9735486.ViewModels
{
using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Threading;
// http://kentb.blogspot.com/2009/04/mvvm-infrastructure-viewmodel.html
public abstract class ViewModel : INotifyPropertyChanged
{
private readonly Dispatcher _dispatcher;
protected ViewModel()
{
if (Application.Current != null)
{
_dispatcher = Application.Current.Dispatcher;
}
else
{
//this is useful for unit tests where there is no application running
_dispatcher = Dispatcher.CurrentDispatcher;
}
}
[field: NonSerialized]
public event PropertyChangedEventHandler PropertyChanged;
protected Dispatcher Dispatcher
{
get { return _dispatcher; }
}
protected virtual void OnPropertyChanged(PropertyChangedEventArgs e)
{
var handler = this.PropertyChanged;
if (handler != null)
{
handler(this, e);
}
}
protected void OnPropertyChanged(string propertyName)
{
OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
}
}
}
namespace SO9735486.ViewModels
{
public abstract class ContentViewModel : ViewModel
{
private readonly string displayName;
protected ContentViewModel(string displayName)
{
this.displayName = displayName;
}
public string DisplayName
{
get { return this.displayName; }
}
}
}
namespace SO9735486.ViewModels
{
public sealed class FirstContentViewModel : ContentViewModel
{
private string name;
public FirstContentViewModel()
: base("First")
{
}
public string Name
{
get { return this.name; }
set
{
if (this.name != value)
{
this.name = value;
this.OnPropertyChanged("Name");
}
}
}
}
}
namespace SO9735486.ViewModels
{
public sealed class SecondContentViewModel : ContentViewModel
{
public SecondContentViewModel()
: base("Second")
{
}
}
}
namespace SO9735486.ViewModels
{
using System.Collections.Generic;
using System.Linq;
public sealed class MainViewModel : ViewModel
{
private readonly ICollection<ContentViewModel> contentViewModels;
private ContentViewModel selectedContentViewModel;
public MainViewModel()
{
this.contentViewModels = new List<ContentViewModel>
{
new FirstContentViewModel(),
new SecondContentViewModel()
};
this.selectedContentViewModel = this.contentViewModels.First();
}
public ICollection<ContentViewModel> ContentViewModels
{
get { return this.contentViewModels; }
}
public ContentViewModel SelectedContentViewModel
{
get { return this.selectedContentViewModel; }
set
{
if (this.selectedContentViewModel != value)
{
this.selectedContentViewModel = value;
this.OnPropertyChanged("SelectedContentViewModel");
}
}
}
}
}
<UserControl x:Class="SO9735486.Views.FirstContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>First Content View</Label>
<TextBox Text="{Binding Name}"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.SecondContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>Second content view</Label>
<Rectangle Fill="Blue" Width="100" Height="30"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<DockPanel>
<ComboBox DockPanel.Dock="Top" ItemsSource="{Binding ContentViewModels}" SelectedItem="{Binding SelectedContentViewModel}" DisplayMemberPath="DisplayName"/>
<ContentControl Content="{Binding SelectedContentViewModel}"/>
</DockPanel>
</UserControl>
第二内容视图
<Application x:Class="SO9735486.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="clr-namespace:SO9735486.ViewModels"
xmlns:v="clr-namespace:SO9735486.Views"
StartupUri="MainWindow.xaml">
<Application.Resources>
<DataTemplate DataType="{x:Type vm:MainViewModel}">
<v:MainView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:FirstContentViewModel}">
<v:FirstContentView/>
</DataTemplate>
<DataTemplate DataType="{x:Type vm:SecondContentViewModel}">
<v:SecondContentView/>
</DataTemplate>
</Application.Resources>
</Application>
<Window x:Class="SO9735486.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow">
</Window>
namespace SO9735486
{
using System.Windows;
using SO9735486.ViewModels;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.Content = new MainViewModel();
}
}
}
namespace SO9735486.ViewModels
{
using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Threading;
// http://kentb.blogspot.com/2009/04/mvvm-infrastructure-viewmodel.html
public abstract class ViewModel : INotifyPropertyChanged
{
private readonly Dispatcher _dispatcher;
protected ViewModel()
{
if (Application.Current != null)
{
_dispatcher = Application.Current.Dispatcher;
}
else
{
//this is useful for unit tests where there is no application running
_dispatcher = Dispatcher.CurrentDispatcher;
}
}
[field: NonSerialized]
public event PropertyChangedEventHandler PropertyChanged;
protected Dispatcher Dispatcher
{
get { return _dispatcher; }
}
protected virtual void OnPropertyChanged(PropertyChangedEventArgs e)
{
var handler = this.PropertyChanged;
if (handler != null)
{
handler(this, e);
}
}
protected void OnPropertyChanged(string propertyName)
{
OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
}
}
}
namespace SO9735486.ViewModels
{
public abstract class ContentViewModel : ViewModel
{
private readonly string displayName;
protected ContentViewModel(string displayName)
{
this.displayName = displayName;
}
public string DisplayName
{
get { return this.displayName; }
}
}
}
namespace SO9735486.ViewModels
{
public sealed class FirstContentViewModel : ContentViewModel
{
private string name;
public FirstContentViewModel()
: base("First")
{
}
public string Name
{
get { return this.name; }
set
{
if (this.name != value)
{
this.name = value;
this.OnPropertyChanged("Name");
}
}
}
}
}
namespace SO9735486.ViewModels
{
public sealed class SecondContentViewModel : ContentViewModel
{
public SecondContentViewModel()
: base("Second")
{
}
}
}
namespace SO9735486.ViewModels
{
using System.Collections.Generic;
using System.Linq;
public sealed class MainViewModel : ViewModel
{
private readonly ICollection<ContentViewModel> contentViewModels;
private ContentViewModel selectedContentViewModel;
public MainViewModel()
{
this.contentViewModels = new List<ContentViewModel>
{
new FirstContentViewModel(),
new SecondContentViewModel()
};
this.selectedContentViewModel = this.contentViewModels.First();
}
public ICollection<ContentViewModel> ContentViewModels
{
get { return this.contentViewModels; }
}
public ContentViewModel SelectedContentViewModel
{
get { return this.selectedContentViewModel; }
set
{
if (this.selectedContentViewModel != value)
{
this.selectedContentViewModel = value;
this.OnPropertyChanged("SelectedContentViewModel");
}
}
}
}
}
<UserControl x:Class="SO9735486.Views.FirstContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>First Content View</Label>
<TextBox Text="{Binding Name}"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.SecondContentView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<StackPanel>
<Label>Second content view</Label>
<Rectangle Fill="Blue" Width="100" Height="30"/>
</StackPanel>
</UserControl>
<UserControl x:Class="SO9735486.Views.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<DockPanel>
<ComboBox DockPanel.Dock="Top" ItemsSource="{Binding ContentViewModels}" SelectedItem="{Binding SelectedContentViewModel}" DisplayMemberPath="DisplayName"/>
<ContentControl Content="{Binding SelectedContentViewModel}"/>
</DockPanel>
</UserControl>
仅对Windows1.xaml.vb进行更改。代码bhind文件应如下所示。问题的答案是，将添加的用户控件的可见性设置为Windows.Visibility.Collapsed，而不是callinf Canvas1.Clear（） Window1.xaml.vb
Class Window1
Private Sub LstItem1_Selected(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs)
Canvas1.Children.Clear()
Canvas1.Children.Add(New UserControl1)
End Sub
Private Sub LstItem2_Selected(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs)
Canvas1.Children.Clear()
Canvas1.Children.Add(New UserControl2)
End Sub
Class Window1
Private U1 As Integer
Private U2 As Integer
Private Sub LstItem1_Selected(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs)
Canvas1.Children.Item(U1).Visibility = Windows.Visibility.Visible
Canvas1.Children.Item(U2).Visibility = Windows.Visibility.Collapsed
End Sub
Private Sub LstItem2_Selected(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs)
Canvas1.Children.Item(U2).Visibility = Windows.Visibility.Visible
Canvas1.Children.Item(U1).Visibility = Windows.Visibility.Collapsed
End Sub
Private Sub Window1_Loaded(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs) Handles Me.Loaded
U1 = Canvas1.Children.Add(New UserControl1)
U2 = Canvas1.Children.Add(New UserControl2)
Canvas1.Children.Item(U1).Visibility = Windows.Visibility.Collapsed
Canvas1.Children.Item(U2).Visibility = Windows.Visibility.Collapsed
End Sub
End Class
你能在我的问题中看到上面贴出的代码吗？如果你对这个boogaart有任何解决方案，请回答我。谢谢你的关注。我得到了答案。我不应该从画布（CanvasForm.Clear）中删除控件，而应该将控件的可见性设置为折叠。我已经发布了这个答案。由于我是这个领域的新手（WinForms和WPF），我不知道Visibility属性。再次感谢您抽出时间。