我试图将两个不同的WPF控件绑定到ViewModel中的同一属性,一个是CheckBox.IsChecked,另一个是Expander.IsExpanded。我想要实现的行为是让CheckBox影响ViewModel(因此也会影响Expander),但不要反过来绑定。类似于:
Checkbox Checked -> ViewModel property set to frue -> Expander.Expand
Checkbox Unchecked -> ViewModel property set to false -> Expander.Collapse
Expander Expanded -> Nothing else affected
Expander Collapsed -> Nothing else affected
以下是 XAML 代码:
<Window x:Class="WpfApplication9.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">
<Expander IsExpanded="{Binding IsChecked, Mode=OneWay}">
<Expander.Header>
<CheckBox IsChecked="{Binding IsChecked}" Content="Is Checked"/>
</Expander.Header>
<TextBlock Text="Expanded!"/>
</Expander>
</Window>
并且这段代码:
using System.ComponentModel;
using System.Windows;
namespace WpfApplication9
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
DataContext = new ViewModel();
}
}
public class ViewModel: INotifyPropertyChanged
{
private bool _isChecked;
public bool IsChecked
{
get { return _isChecked; }
set
{
_isChecked = value;
NotifyPropertyChange("IsChecked");
}
}
protected void NotifyPropertyChange(string PropertyName)
{
PropertyChanged(this, new PropertyChangedEventArgs(PropertyName));
}
public event PropertyChangedEventHandler PropertyChanged = delegate { };
}
}
现在我的问题是,一旦我点击展开/折叠Expander,绑定似乎就停止工作了。有人能解释一下这是为什么,我怎样才能实现这个功能?先谢谢了!