WPF MVVM. Left DoubleClick on ListViewItem

Question

我想要的:如果我在ListViewItem上做一个左双击，我想调用一个方法。

What I have:

Xaml:

<ListView ScrollViewer.HorizontalScrollBarVisibility="Hidden" 
Name="StructListView"
Margin="15" 
Grid.Row="2" 
BorderThickness="0" 
SelectedItem="{Binding SelectedStructObject}" 
ItemsSource="{Binding StructObjects, Mode=TwoWay}"
HorizontalAlignment="Left"
HorizontalContentAlignment="Left">
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseDoubleClick">
<i:InvokeCommandAction 
Command="{Binding Command}"
CommandParameter="{Binding ElementName=StructListView, Path=SelectedItem}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
...

MainViewModel:

public class MainViewModel : BaseViewModel
{
private StructElement _selectedStructObject;
public StructElement SelectedStructObject
{
get { return _selectedStructObject; }
set
{
if (_selectedStructObject != value)
{
_selectedStructObject = value;
OnPropertyChanged();
}
}
}
public RelayCommand Command { get; set; }
public ObservableCollection<StructElement> StructObjects { get; set; }
private StructElement _structElement;
public StructElement StructObject
{
get { return _structElement; }
set
{
if (_structElement != value)
{
_structElement = value;
OnPropertyChanged();
}
}
}

public MainViewModel()
{
Command = new RelayCommand(o => { //Method; });

StructObjects = new ObservableCollection<StructElement>();         
}
}

RelayCommand:

public class RelayCommand : ICommand
{
private readonly Action<object> execute;
private readonly Predicate<object> canExecute;
public RelayCommand(Action<object> execute)
: this(execute, null)
{
}
public RelayCommand(Action<object> execute, Predicate<object> canExecute)
{
if (execute == null)
{
throw new ArgumentNullException("execute");
}
this.execute = execute;
this.canExecute = canExecute;
}
public event EventHandler CanExecuteChanged
{
add { CommandManager.RequerySuggested += value; }
remove { CommandManager.RequerySuggested -= value; }
}
public bool CanExecute(object parameter)
{
if (canExecute == null)
{
return true;
}
return canExecute(parameter);
}
public void Execute(object parameter)
{
execute(parameter);
}
}

我知道如果我工作我可以用类似事件:

void OnMouseDoubleClick(Object sender, MouseButtonEventArgs e)
{
if (e.ChangedButton == MouseButton.Left)
{
// Method
}
}

但是因为我正在使用RelayCommand，我没有像MouseButtonEventArgs这样的事件?我想到了"触发"。OnMouseDoubleClick与RelayCommand?

我对编程和WPF很熟悉，所以如果你有关于我应该阅读的东西的进一步信息来理解解决方案，我会很感激的。

谢谢。

Answer 1

我遇到了一个与链接不同的解决方案。

在我的XAML中，我使用"EventToCommand"从MVVMLight:

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

我使我的RelayCommand通用，所以我可以传递一个事件(我希望我得到了正确的描述):

public class RelayCommand : ICommand
{
private readonly Action<object> execute;
private readonly Predicate<object> canExecute;
public RelayCommand(Action<object> execute)
: this(execute, null)
{
}
public RelayCommand(Action<object> execute, Predicate<object> canExecute)
{
if (execute == null)
{
throw new ArgumentNullException("execute");
}
this.execute = execute;
this.canExecute = canExecute;
}
public event EventHandler CanExecuteChanged
{
add { CommandManager.RequerySuggested += value; }
remove { CommandManager.RequerySuggested -= value; }
}
public bool CanExecute(object parameter)
{
if (canExecute == null)
{
return true;
}
return canExecute(parameter);
}
public void Execute(object parameter)
{
execute(parameter);
}
}

在我的MainViewModel中，我声明了一个带有MouseButtonEventArgs的RelayCommand，并传递了一个方法来检查MouseButton是否是左键并做一些事情:

public RelayCommand<MouseButtonEventArgs> LightCommand { get; set; }
public void dosomething(MouseButtonEventArgs e)
{
if (e.ChangedButton == MouseButton.Left) 
{
MessageBox.Show(e.OriginalSource.GetType().ToString());
}           
}

public MainViewModel()
{       
LightCommand = new RelayCommand<MouseButtonEventArgs>(dosomething);
}