c# - Mvvmlight UpdateSourceTrigger 不工作

Question

xaml

<DataGrid ItemsSource="{Binding Products}" CanUserAddRows="False" AutoGenerateColumns="False" SelectedItem="{Binding SelectedProduct}">
<i:Interaction.Triggers>
    <i:EventTrigger EventName="CellEditEnding">
        <cmd:EventToCommand Command="{Binding ProdcutCellEditCmd,UpdateSourceTrigger=PropertyChanged}" PassEventArgsToCommand="True"></cmd:EventToCommand>
    </i:EventTrigger>
</i:Interaction.Triggers>
<DataGrid.Columns>
    <DataGridTextColumn Binding="{Binding id}" Header="ID" IsReadOnly="True"></DataGridTextColumn>
    <DataGridTextColumn Binding="{Binding ParentLCSKU}" Header="LCSKU(Parent)" IsReadOnly="True"></DataGridTextColumn>
    <DataGridTextColumn Binding="{Binding ChildLCSKU}" Header="LCSKU(Child)" IsReadOnly="True"></DataGridTextColumn>
    <DataGridComboBoxColumn ItemsSource="{Binding Source={StaticResource ProductColors}}" SelectedValueBinding="{Binding Color}" Header="颜色" IsReadOnly="True"></DataGridComboBoxColumn>
    <DataGridComboBoxColumn ItemsSource="{Binding Source={StaticResource ProductSizes}}" SelectedValueBinding="{Binding Size}" Header="尺寸" IsReadOnly="True"></DataGridComboBoxColumn>
    <DataGridComboBoxColumn ItemsSource="{Binding Source={StaticResource ProductCategories}}" SelectedValueBinding="{Binding Category}" Header="类别" IsReadOnly="True"></DataGridComboBoxColumn>
    <DataGridTextColumn Binding="{Binding Cost}" Header="成本"></DataGridTextColumn>
    <DataGridCheckBoxColumn Binding="{Binding IsOEM,UpdateSourceTrigger=PropertyChanged}" Header="OEM"></DataGridCheckBoxColumn>
</DataGrid.Columns>

View 模型

public ProductVM()
{
    ProdcutCellEditCmd = new RelayCommand<DataGridCellEditEndingEventArgs>(prodcutDataGridCellEditEnding);

}
public RelayCommand<DataGridCellEditEndingEventArgs> ProdcutCellEditCmd { get; set; }
private void prodcutDataGridCellEditEnding(DataGridCellEditEndingEventArgs e)
{
    if (e.EditAction == DataGridEditAction.Commit)
    {
        var prodcut = e.Row.DataContext as BaseProduct;
        SelectedProduct = prodcut;
        productSave();
    }
}

我想在选中或取消选中复选框后触发 CellEditEnding 事件，但此事件仅在单元格失去焦点时触发。

这有什么问题吗？

抱歉我的英语不好。

Answer 1

这是正常行为，因为事件名称是 CellEditEnding。这意味着事件在单元格编辑完成后触发。

我建议您绑定(bind)到 CheckBox 中的 Command 属性。如果你将 DataGrid 放在 Window 中，你应该这样写:

<CheckBox Header="OEM" IsChecked="{Binding IsOEM,UpdateSourceTrigger=PropertyChanged}}"
                 Command="{Binding DataContext.ProdcutCellEditCmd, RelativeSource=
                {RelativeSource AncestorType=Window, Mode=FindAncestor}}"}" />

如果你把DataGrid放在UserControl中，你应该这样写:

<CheckBox Header="OEM" IsChecked="{Binding IsOEM,UpdateSourceTrigger=PropertyChanged}}"
                 Command="{Binding DataContext.ProdcutCellEditCmd, RelativeSource=
                {RelativeSource AncestorType=UserControl, Mode=FindAncestor}}"}" />