在应用程序中,我想绑定(bind)来自 2 个不同 View 模型的数据。我必须将数据上下文设置为两个不同的 View 模型。
当我使用两个不同的 View 模型时,只有最后设置的数据上下文优先。
因此,我有一个CombinedDataContext 类和其他 View 模型类。
我可以更新 View 模型,但它没有显示在 View 上。
View 模型1
public class Data1 : INotifyPropertyChanged
{
private string _string1;
public string String1
{
get { return _string1; }
set { _string1 = value; onPropertyChnaged("String1"); }
}
private void onPropertyChnaged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
public event PropertyChangedEventHandler PropertyChanged;
}
View 模型2
public class Data2 : INotifyPropertyChanged
{
private string _string2;
public string String2
{
get { return _string2; }
set { _string2 = value; onPropertyChnaged("String2");}
}
private void onPropertyChnaged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
public event PropertyChangedEventHandler PropertyChanged;
}
浏览次数:
public partial class MainWindow : Window
{
Data12 d12 = new Data12 { };
public MainWindow()
{
InitializeComponent();
DataContext = d12;
}
private void button_Click(object sender, RoutedEventArgs e)
{
ViewModel_1();
ViewModel_2();
}
private void ViewModel_1()
{
var viewmodel = DataContext as Data12;
viewmodel.Data1.String1 = textBox.Text;
}
private void ViewModel_2()
{
var viewmodel = DataContext as Data12;
viewmodel.Data1.String1 = textBox.Text;
}
}
组合 View 模型:
class Data12
{
public Data1 Data1 = new Data1();
public Data2 Data2= new Data2();
}
Xaml 文件:
<Grid>
<Label x:Name="label" HorizontalAlignment="Left" Margin="92,61,0,0" VerticalAlignment="Top" Content="{Binding Data1.String1}" />
<Label x:Name="label1" Content="{Binding Data2.String2}" HorizontalAlignment="Left" Margin="349,61,0,0" VerticalAlignment="Top" />
<TextBox x:Name="textBox" HorizontalAlignment="Left" Height="23" Margin="65,153,0,0" TextWrapping="Wrap" Text="TextBox" VerticalAlignment="Top" Width="120"/>
<TextBox x:Name="textBox1" HorizontalAlignment="Left" Height="23" Margin="360,153,0,0" TextWrapping="Wrap" Text="TextBox" VerticalAlignment="Top" Width="120"/>
<Button x:Name="button" Content="Button" HorizontalAlignment="Left" Margin="205,246,0,0" VerticalAlignment="Top" Width="75" Click="button_Click" />
</Grid>
没有 Nullreference,但绑定(bind)不起作用。我什至尝试实例化内部属性,但没有成功。请帮我解决这个问题。
最佳答案
您无法绑定(bind)字段,因此只需将它们转换为属性即可:
class Data12
{
public Data12()
{
this.Data1 = new Data1();
this.Data2 = new Data2();
}
public Data1 Data1 { get; private set; }
public Data2 Data2 { get; private set; }
}
正如 @Clemens 评论的那样,这可以缩短为
class Data12
{
public Data1 Data1 { get; } = new Data1();
public Data2 Data2 { get; } = new Data2();
}
关于c# - 如何在wpf中的窗口中设置多个Datacontext,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/47083213/