将DoubleClick Command从DataGrid Row绑定到VM [英] Bind DoubleClick Command from DataGrid Row to VM

问题描述

我有一个Datagrid，不喜欢我的解决方法，在我的viewmodel上点击（已选择的）行启动双击命令。

I have a Datagrid and don't like my workaround to fire a double click command on my viewmodel for the clicked (aka selected) row.

查看： / p>

View:

   <DataGrid  EnableRowVirtualization="True"
              ItemsSource="{Binding SearchItems}"
              SelectedItem="{Binding SelectedItem}"
              SelectionMode="Single"
              SelectionUnit="FullRow">

        <i:Interaction.Triggers>
            <i:EventTrigger EventName="MouseDoubleClick">
                <cmd:EventToCommand Command="{Binding MouseDoubleClickCommand}" PassEventArgsToCommand="True" />
            </i:EventTrigger>
        </i:Interaction.Triggers>
        ...
  </DataGrid>

ViewModel：

ViewModel:

    public ICommand MouseDoubleClickCommand
    {
        get
        {
            if (mouseDoubleClickCommand == null)
            {
                mouseDoubleClickCommand = new RelayCommand<MouseButtonEventArgs>(
                    args =>
                    {
                        var sender = args.OriginalSource as DependencyObject;
                        if (sender == null)
                        {
                            return;
                        }
                        var ancestor = VisualTreeHelpers.FindAncestor<DataGridRow>(sender);
                        if (ancestor != null)
                        {
                            MessengerInstance.Send(new FindDetailsMessage(this, SelectedItem.Name, false));
                        }
                    }
                    );
            }
            return mouseDoubleClickCommand;
        }
    }

我想摆脱视图相关代码一个具有依赖对象和视觉树助手）在我的视图模型，因为这打破了可测试性不知何故。但是在另一方面，这种方式我避免了，当用户不点击行，但在标题上，例如，发生一些事情。

I want to get rid of the view related code (the one with the dependency object and the visual tree helper) in my view model, as this breaks testability somehow. But on the other hand this way I avoid that something happens when the user doesn't click on a row but on the header for example.

PS：我试过有一个看看附加的行为，但我不能从工作中的Skydrive下载，所以一个内置解决方案是最好的。

PS: I tried having a look at attached behaviors, but I cannot download from Skydrive at work, so a 'built in' solution would be best.

推荐答案

为什么不使用 CommandParameter ？

<DataGrid x:Name="myGrd"
          ItemsSource="{Binding SearchItems}"
          SelectedItem="{Binding SelectedItem}"
          SelectionMode="Single"
          SelectionUnit="FullRow">

    <i:Interaction.Triggers>
        <i:EventTrigger EventName="MouseDoubleClick">
            <cmd:EventToCommand Command="{Binding MouseDoubleClickCommand}"  
                                CommandParameter="{Binding ElementName=myGrd, Path=SelectedItem}" />
        </i:EventTrigger>
    </i:Interaction.Triggers>
    ...
</DataGrid>

您的命令如下：

public ICommand MouseDoubleClickCommand
{
    get
    {
        if (mouseDoubleClickCommand == null)
        {
            mouseDoubleClickCommand = new RelayCommand<SearchItem>(
                item =>
                {
                    var selectedItem = item;
                });
        }

        return mouseDoubleClickCommand;
    }
}

编辑：我现在使用这个而不是 Interaction.Triggers ：

I now use this instead of Interaction.Triggers:

<DataGrid.InputBindings>
    <MouseBinding MouseAction="LeftDoubleClick"
                  Command="{Binding Path=MouseDoubleClickCommand}"
                  CommandParameter="{Binding ElementName=myGrd, Path=SelectedItem}" />
</DataGrid.InputBindings>

这篇关于将DoubleClick Command从DataGrid Row绑定到VM的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！