要实现包含用户控件的视图模型,并在用户控件属性重置时更新视图模型,可以按照以下步骤进行:
public class UserControlViewModel : INotifyPropertyChanged
{
private string _userControlProperty;
public string UserControlProperty
{
get { return _userControlProperty; }
set
{
if (_userControlProperty != value)
{
_userControlProperty = value;
OnPropertyChanged(nameof(UserControlProperty));
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string propertyName)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
// 创建视图模型并设置为数据上下文
var viewModel = new UserControlViewModel();
DataContext = viewModel;
}
}
public partial class UserControl : System.Windows.Controls.UserControl
{
public static readonly DependencyProperty UserControlPropertyProperty =
DependencyProperty.Register("UserControlProperty", typeof(string), typeof(UserControl), new PropertyMetadata(null, OnUserControlPropertyPropertyChanged));
public string UserControlProperty
{
get { return (string)GetValue(UserControlPropertyProperty); }
set { SetValue(UserControlPropertyProperty, value); }
}
private static void OnUserControlPropertyPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var userControl = (UserControl)d;
var viewModel = (UserControlViewModel)userControl.DataContext;
// 更新视图模型的属性
viewModel.UserControlProperty = (string)e.NewValue;
}
public UserControl()
{
InitializeComponent();
}
}
通过以上步骤,就可以在用户控件的属性重置时,自动更新视图模型中的属性,并进而更新视图。
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