使用WPF中的MVVM更新其他绑定的绑定

时间:2015-06-12 13:35:22

标签: c# wpf xaml mvvm binding

有没有人有任何关于如何解决我的问题的建议?我有一个数据网格绑定到ModelCheckoutRecord个对象(ListModelCheckoutRecords)的集合。我将所选项目绑定到ModelCheckoutRecordSelectedItemModelCheckoutRecord)。在所选项的绑定中,我想更新另一个datagrid和gridsplitter(ResponseVisibility)的可见性绑定。从其他绑定更新绑定的能力似乎不起作用?

我的XAML行如下:

            <Grid>
                <Grid.RowDefinitions>
                    <View:RowDefinitionExtended Height="Auto"/>
                    <RowDefinition Height="Auto"/>
                    <RowDefinition Height="Auto"/>
                </Grid.RowDefinitions>
                <DataGrid AutoGenerateColumns="True" ItemsSource="{Binding ListModelCheckoutRecord}" SelectedItem="{Binding SelectedModelCheckoutRecord}" MouseLeftButtonDown="DataGrid_MouseLeftButtonDown" CommandManager.PreviewExecuted="DataGrid_DeletePreviewExecuted" IsReadOnly="False" CanUserAddRows="False" CanUserDeleteRows="True" Margin="15" Grid.Row="0"/>
                <GridSplitter HorizontalAlignment="Stretch" Visibility="{Binding ResponseVisibility}" Grid.Row="1"/>
                <DataGrid AutoGenerateColumns="True" ItemsSource="{Binding ListModelResponseRecord}" SelectedItem="{Binding SelectedModelResponseRecord}" MouseLeftButtonDown="DataGrid_MouseLeftButtonDown" IsReadOnly="False" CanUserAddRows="False" CanUserDeleteRows="False" Visibility="{Binding ResponseVisibility}" Margin="15" Grid.Row="2"/>
            </Grid>

导致我麻烦的精简代码如下:

    private Visibility responseVisibility = Visibility.Visible;
    public Visibility ResponseVisibility
    {
        get { return responseVisibility; }
        set
        {
            if (value == responseVisibility)
            {
                return;
            }

            responseVisibility = value;
            RaisePropertyChanged("ResponseVisibility");
        }
    }

    private List<ModelCheckoutRecord> listModelCheckoutRecord;
    public List<ModelCheckoutRecord> ListModelCheckoutRecord
    {
        get { return listModelCheckoutRecord; }
        set
        {
            if (value == listModelCheckoutRecord)
            {
                return;
            }

            listModelCheckoutRecord = value;
            RaisePropertyChanged("ListModelCheckoutRecord");

            ResponseVisibility = Visibility.Collapsed;
        }
    }

    private ModelCheckoutRecord selectedModelCheckoutRecord;
    public ModelCheckoutRecord SelectedModelCheckoutRecord
    {
        get { return selectedModelCheckoutRecord; }
        set
        {
            if (value == null)
            {
                ResponseVisibility = Visibility.Collapsed;
                return;
            }

            else
            {
                ResponseVisibility = Visibility.Visible;
            }

            if (selectedModelCheckoutRecord == value)
            {
                return;
            }

            RaisePropertyChanged("SelectedModelCheckoutRecord");
        }
    }

由于

理查德

1 个答案:

答案 0 :(得分:2)

假设您确实希望在仅null SelectedItem的情况下获得折叠可见性,那么实际上不需要使用代码。以下XAML将完成这项工作。

只需为源DataGrid提供一个名称(我在以下示例中假设Grid为名称)并在目标DataGrid中使用样式,如下所示:

<DataGrid x:Name="TargetGridJustToShowWhereThisGoes">
    <DataGrid.Style>
        <Style TargetType="DataGrid">
            <Style.Triggers>
                <DataTrigger Binding="{Binding ElementName=Grid, Path=SelectedItem}" Value="{x:Null}">
                    <Setter Property="Visibility" Value="Collapsed" />
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </DataGrid.Style>
</DataGrid>