我的主窗口中有 3 个用户控件，在我的用户控件 1 中，我有一个带有一些名称的列表框。当我们启动应用程序时，用户控件 2 和 3 不可见。
当我在 usercontrol1 的列表框中选择某个名称时，usercontrol2 应该出现在我的主窗口上，当我选择其他名称时，usercontrol3 应该出现在我的主窗口上。为此苦苦挣扎，请帮助我，我是新手
这是我的 UserControlXaml 代码
<UserControl x:Class="Wpf_MVVM.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"
x:Name="uc1" Height="Auto" Width="Auto">
<Grid>
<ListBox Name="listbox" ItemsSource="{Binding mylist}" HorizontalAlignment="Left" Height="310" VerticalAlignment="Top" Width="150" Margin="0,40,0,0" FontSize="15">
</ListBox>
<Label Content="Conversations" HorizontalAlignment="Left" VerticalAlignment="Top" Height="40" Width="150" FontSize="20" Background="SkyBlue"/>
<Button Content="Create New Chat" Height="30" HorizontalAlignment="Left" Margin="0,350,0,0" VerticalAlignment="Top" Width="150"/>
</Grid>
</UserControl>
这是我的 .cs 代码
public partial class UserControl1 : UserControl
{
User1 User1 = new User1();
public UserControl1()
{
InitializeComponent();
this.DataContext = User1;
}
}
public class User1
{
private ObservableCollection<string> _mylist = new ObservableCollection<string>();
public ObservableCollection<string> mylist { get { return _mylist; } }
public User1()
{
mylist.Add("Name1");
mylist.Add("Name2");
mylist.Add("Name3");
mylist.Add("Name4");
}
这是我的 mainwindow.xaml 代码
<Window x:Class="Wpf_MVVM.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:Wpf_MVVM"
Title="MainWindow" Background="SlateGray" Height="420" Width="550" >
<Window.Resources>
<BooleanToVisibilityConverter x:Key="VisibilityConverter" />
</Window.Resources>
<Grid>
<local:UserControl1 x:Name="uc1" HorizontalAlignment="Left" VerticalAlignment="Top"/>
<StackPanel>
<local:UserControl2 x:Name="uc2" Visibility="{Binding SelectedItem, Converter={StaticResource VisibilityConverter}}" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="150,29,0,0" />
<local:UserControl3 x:Name="uc3" Visibility="{Binding SelectedItem1, Converter={StaticResource VisibilityConverter}}" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="340,29,0,0"/>
</StackPanel>
</Grid>
</Window>
这是我的 usercontrol2 和 3 的视图模型代码
public class User : INotifyPropertyChanged
{
private bool _selectedItem;
public bool SelectedItem
{
get { return _selectedItem; }
set
{
_selectedItem = value;
PropertyChanged(this, new PropertyChangedEventArgs("SelectedItem"));
}
}
private bool _selectedItem1;
public bool SelectedItem1
{
get { return _selectedItem1; }
set
{
_selectedItem1 = value;
PropertyChanged(this, new PropertyChangedEventArgs("SelectedItem1"));
}
}
public class BooleanToVisibilityConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
return value == null ? Visibility.Collapsed : Visibility.Visible;
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
return null;
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void Notify(string propertyName)
{
var handler = PropertyChanged;
if (handler != null)
handler(this, new PropertyChangedEventArgs(propertyName));
}
private readonly ObservableCollection<string> items = new ObservableCollection<string>();
private string text;
private readonly ObservableCollection<string> newitems = new ObservableCollection<string>();
private string newtext;
public class Command : ICommand
{
private readonly Action action;
public Command(Action action)
{
this.action = action;
}
public bool CanExecute(object parameter)
{
return true;
}
public event EventHandler CanExecuteChanged;
public void Execute(object parameter)
{
action();
}
}
private readonly ICommand addCommand;
private readonly ICommand sendCommand;
public User()
{
addCommand = new Command(() => items.Add(Text));
sendCommand = new Command(() => newitems.Add(NewText));
}
public IEnumerable<string> Items
{
get { return items; }
}
public IEnumerable<string> NewItems
{
get { return newitems; }
}
public ICommand AddCommand
{
get { return addCommand; }
}
public ICommand SendCommand
{
get { return sendCommand; }
}
public string Text
{
get { return text; }
set
{
if (text == value)
return;
text = value;
Notify("Text");
}
}
public string NewText
{
get { return newtext; }
set
{
if (newtext == value)
return;
newtext = value;
Notify("NewText");
}
}
}
}