Question

我遇到的问题是让我的按钮使用绑定。我不确定要设置DataContext的内容。我的绑定出现了这个错误：

System.Windows.Data Error: 40 : BindingExpression path error: 'ClickMeCommand' property not found on 'object' ''Person' (HashCode=13029119)'. BindingExpression:Path=ClickMeCommand; DataItem='Person' (HashCode=13029119); target element is 'Button' (Name=''); target property is 'Command' (type 'ICommand')

我在这里做的是我在XAML中有一个ListView，我有一个有三列的网格视图。一列存储Person对象中的Name，第二列存储Person对象中的Date，第三列对于列表中的所有内容都是相同的，一个按钮。单击该按钮时，我想执行一个命令从我的observable集合中删除该任务并更新列表。我知道怎么做但我无法获得按钮的绑定命令。

<ListView x:Name="List" HorizontalAlignment="Left" Margin="0,0,0,-2"` Width="292" HorizontalContentAlignment="Stretch" ScrollViewer.HorizontalScrollBarVisibility="Disabled" Height="Auto">
                    <ListView.ItemContainerStyle>
                        <Style TargetType="{x:Type ListViewItem}">
                            <Setter Property="HorizontalContentAlignment" Value="Stretch" />
                    </Style>
                </ListView.ItemContainerStyle>
                <ListView.View>
                    <GridView>
                        <GridView.ColumnHeaderContainerStyle>
                            <Style BasedOn="{StaticResource {x:Type GridViewColumnHeader}}" TargetType="{x:Type GridViewColumnHeader}">
                                <Setter Property="IsHitTestVisible" Value="False"/>
                            </Style>
                        </GridView.ColumnHeaderContainerStyle>
                        <GridViewColumn x:Name="Column1" Header="Assignment" DisplayMemberBinding="{Binding Name}" Width="190"/>
                        <GridViewColumn x:Name="Column2" Header="Date" DisplayMemberBinding="{Binding Date}" Width="45"/>
                        <GridViewColumn Header="Edit" Width="35" CellTemplate="{StaticResource editColumnTemplate}">
                        </GridViewColumn>
                    </GridView>
                </ListView.View>
            </ListView>


<Window.Resources>
        <DataTemplate x:Key="editColumnTemplate">
            <StackPanel Orientation="Horizontal">
                <Button x:Name="deleteButton" Content="X"  Command="{Binding Path=ClickMeCommand}" HorizontalAlignment="Stretch"/>
            </StackPanel>
        </DataTemplate>
</Window.Resources>

//

private class Person
        {
            public String Name { get; set; }
            public String Date { get; set; }

        }

在我的代码中，我创建了一个新选项卡并在其中添加了一个列表视图。每次我添加一个新人时，它会在列表中添加一行，其中包含他/她的姓名/日期和第三列上的按钮。

 public MainWindow(){
     InitializeComponent();
     this.DataContext = new MainViewModel();
}
TabItem newItem = new TabItem();
ListView newList = new ListView();
ObservableCollection<TabItem> newSource = new ObservableCollection<TabItem>();
newList.ItemsSource = newSource;
TabControl.Items.Add(newItem);

从上面可以看到，该按钮绑定到命令ClickMeCommand。这是班级：

 public class MainViewModel
{
    public MainViewModel()
    {

    }

    private ICommand clickMeCommand;
    public ICommand ClickMeCommand
    {
        get
        {
            if (clickMeCommand == null)
                clickMeCommand = new RelayCommand(i => this.ClickMe(), null);
            return clickMeCommand;
        }
    }

    private void ClickMe()
    {
        MessageBox.Show("You Clicked Me");
    }
}    
public class RelayCommand : ICommand
{
    readonly Action<object> execute;
    readonly Predicate<object> canExecute;

    public RelayCommand(Action<object> executeDelegate, Predicate<object> canExecuteDelegate)
    {
        execute = executeDelegate;
        canExecute = canExecuteDelegate;
    }

    bool ICommand.CanExecute(object parameter)
    {
        return canExecute == null ? true : canExecute(parameter);
    }

    event EventHandler ICommand.CanExecuteChanged
    {
        add { CommandManager.RequerySuggested += value; }
        remove { CommandManager.RequerySuggested -= value; }
    }

    void ICommand.Execute(object parameter)
    {
        execute(parameter);
    }
}

为什么我的按钮的命令绑定不起作用？

0 个答案: