Question

我是WPF C＃世界的新手。我在构造函数中有一个方法，它将子元素添加到堆栈面板中。我有2个xaml文件。 mainone有一个stackpanel，另一个有一个标签。

MainWindow查看：

<Grid Grid.Row="1" Name="VoltageChannels" >
        <StackPanel Height="Auto" Name="stackPanel" Width="Auto" MinHeight="300"> </StackPanel>
    </Grid>

<Button Content="Refresh All" Command="{Binding AddChildCommand}"  Name="RefreshAllBtn" />


public void OnChildAdd()
    {
        foreach (VoltageBoardChannel mVoltageChannelViewModel in mVoltageViewModel.VoltageChannelList)
        {
            VoltageChannelView mVoltageChannelView = new VoltageChannelView();
            mVoltageChannelView.Margin = new Thickness(2);
            mVoltageChannelView.ChannelInfo = mVoltageChannelViewModel;
            stackPanel.Children.Add(mVoltageChannelView);
        }
    }

我想从我的viewmodel类访问此方法，以通过单击按钮添加子项。基本上我有一个列表，其中包含一组项目。按钮单击时应显示这些项目:)这是View和ViewModel类：

视图模型：

public viewModel()
{

}
public List<VoltageBoardChannel> VoltageChannelList
    {
        get 
        { 
            return channelList; 
        }

        set
        { 
            channelList = value;
            OnPropertyChanged("ChannelList");
        }
    }

List<VoltageBoardChannel> channelList = new List<VoltageBoardChannel>(0);

    // VoltageBoardChannel has Channel name and avalable as property.
    List<VoltageBoardChannel> redhookChannels = new List<VoltageBoardChannel>
    {
         new VoltageBoardChannel { ChannelName = "", IsAvailable = false},
         new VoltageBoardChannel { ChannelName = "VDD_IO_AUD", IsAvailable = true},
         new VoltageBoardChannel { ChannelName = "VDD_CODEC_AUD", IsAvailable = true},
         new VoltageBoardChannel { ChannelName = "VDD_DAL_AUD", IsAvailable = true},
         new VoltageBoardChannel { ChannelName = "VDD_DPD_AUD", IsAvailable = true},             
    };

    private ICommand mRefreshAllCommand;
    public ICommand AddChildCommand
    {
        get
        {
            if (mRefreshAllCommand == null)
                mRefreshAllCommand = new DelegateCommand(new Action(mRefreshAllCommandExecuted), new Func<bool>(mRefreshAllCommandCanExecute));

            return mRefreshAllCommand;
        }
        set
        {
            mRefreshAllCommand = value;
        }
    }

    public bool mRefreshAllCommandCanExecute()
    {
        return true;
    }

    public void mRefreshAllCommandExecuted()
    {                               
        VoltageChannelList = bavaria1Channels;          
        // Call OnChildAdd Method here                      
    }

XAML查看哪个有我的标签：

<Label Grid.Column="0" Content="{Binding ChannelName}" Height="25" Width="120" Name="VoltageLabel" />

VoltageBoard频道类：

public class VoltageBoardChannel
{
    public string ChannelName { get; set; }
    public bool IsAvailable { get; set; }
}

点击按钮时调用的方法。点击后我想调用OnChildAdd()方法，以便将LIST中的这些项目列表添加到我的堆栈面板中。有可能???

Answer 1

在xaml：

<Button Command={Binding AddChildCommand} />

在你的viewmodel中：

public ICommand AddChildCommand { get; private set; }

然后在viewmodel的构造函数中，将AddChildCommand设置为实现ICommand的对象。然后，此命令可以调用您的OnChildAdd()方法。（here是规范）

更好的方法是将stackpanel的Children绑定到视图模型中的属性，然后将VoltageChannelView添加到该属性中。

无法在按钮单击时从ViewModel添加子项

1 个答案: