通过事件到命令行为，在条目未聚焦时从列表视图发送所选对象

Question

我有一个列表视图，在列表视图中有一个输入框。我想在入口框失去焦点后运行一些代码，我已经使用xct事件来命令行为，但我希望该命令从入口所在的listview中接收对象。

(sudo xaml(

<ListView Name = ReportGrid>
<DataTemplate>
<ViewCell>
<StackLayout>
<Entry Text="0.00" VerticalOptions="Center" FontSize="16" BackgroundColor="White" Margin="10, 0, 0, 0">
<Entry.Behaviors
<behaviors:EventToCommandBehavior EventName="Unfocused" Command="{Binding Source={Reference CountLocationTabView}, Path=BindingContext.QtyEntryUnfocused}" 
CommandParameter="{Binding Source={Reference ReportGrid}, Path=SelectedItem}" />
</Entry.Behaviors>
</Entry>
<StackLayout/>
<ViewCell/>
<DataTemplate/>
<ListView/>

我看到过这样的例子，列表视图中的事件被转换为命令，但其中的元素呢？提前谢谢。

Answer 1

基于您的代码，我创建了一个简单的演示，它运行正常。

您可以参考以下代码：

<ListView ItemsSource="{Binding items}" HasUnevenRows="True" HeightRequest="240" x:Name="Listview">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Frame Padding="0" >
<Grid Padding="0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="0.5*"></ColumnDefinition>
<ColumnDefinition Width="3*"></ColumnDefinition>
<ColumnDefinition Width="3*"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Label x:Name="DistNumber" Text="{Binding DistNumber}" FontSize="18"   Grid.Column="1" HorizontalTextAlignment="Start" VerticalOptions="Center"/>
<Entry  x:Name="CountEntry" Placeholder="Choose Quantity" 
Text="{Binding Count}" 

Grid.Column="2" HorizontalTextAlignment="Center" >
<Entry.Behaviors>
<behaviors:EventToCommandBehavior 
EventName="Unfocused" 
Command="{Binding Path=BindingContext.EntryUnfocused, Source={x:Reference Listview}}" CommandParameter="{Binding .}" />
</Entry.Behaviors>
</Entry>

</Grid>
</Frame>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>

ViewModel是：

public class MyViewModel
{
public ObservableCollection<SomeItem> items { get; set; }
public ICommand EntryUnfocused { get; protected set; }

public MyViewModel() {
items = new ObservableCollection<SomeItem>();
items.Add(new SomeItem { Name = "item1", DistNumber = "1", Count = 1,Quantity = 1 });
items.Add(new SomeItem { Name = "item2", DistNumber = "2", Count = 2, Quantity = 2 });
items.Add(new SomeItem { Name = "item3", DistNumber = "3", Count = 3, Quantity = 3 });
items.Add(new SomeItem { Name = "item4", DistNumber = "4", Count = 4, Quantity = 4 });
items.Add(new SomeItem { Name = "item5", DistNumber = "5", Count = 5, Quantity = 5 });
items.Add(new SomeItem { Name = "item6", DistNumber = "6", Count = 6, Quantity = 6 });

EntryUnfocused = new Command(CompletedCommandExecutedAsync);
}
private void CompletedCommandExecutedAsync(Object obj)
{
SomeItem item = (SomeItem)obj;
System.Diagnostics.Debug.WriteLine("<----- item Name = " + item.Name + "<-----> item Count = " + item.Count);
}
}