首页 > 解决方案 > 刷新关于 Caliburn Micro WPF 中的属性更改的视图

问题描述

有一个视图,它有一个 BindingList 属性。这负责存储工作项,添加和删除。后端工作正常,但 UI 未更新。

风景:

<ListBox Grid.Row="7" Grid.Column="0" Grid.ColumnSpan="2" x:Name="WorkPieces" HorizontalAlignment="Stretch">
    <ListBox.ItemTemplate>
        <DataTemplate>
            <Grid HorizontalAlignment="Stretch">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="auto" />
                    <ColumnDefinition Width="auto" />
                    <ColumnDefinition Width="auto" />
                    <ColumnDefinition Width="auto" />
                    <ColumnDefinition Width="auto" />
                    <ColumnDefinition Width="auto" />
                    <ColumnDefinition Width="auto" />
                    <ColumnDefinition Width="auto" />
                    <ColumnDefinition Width="auto" />
                </Grid.ColumnDefinitions>

                <TextBlock Grid.Column="1" x:Name="DisplayName" Text="{Binding DisplayName}" MinWidth="40
                           " FontWeight="Bold"/>
                <TextBlock Grid.Column="2" Text="{x:Static lang:Resources.Txt_W}" />
                <TextBox Grid.Column="3" x:Name="Width" MinWidth="50" Text="{Binding Width}" TextAlignment="Right"/>
                <TextBlock Grid.Column="4" Text=" x " />
                <TextBlock Grid.Column="5" Text="{x:Static lang:Resources.Txt_L}" />
                <TextBox Grid.Column="6" x:Name="Length" MinWidth="50"  Text="{Binding Length}" TextAlignment="Right"/>

                <Button Grid.Row="0" Grid.Column="7" Margin="5" BorderThickness="0" Background="Transparent"
                        Visibility="{Binding IsLast, Converter={StaticResource Converter}}">
                    <Image Source ="/Images/plus-sign.png" Height="16" Width="16" />
                    <i:Interaction.Triggers>
                        <i:EventTrigger EventName="Click">
                            <cal:ActionMessage MethodName="AddNewWorkPiece" />
                        </i:EventTrigger>
                    </i:Interaction.Triggers>
                </Button>

                <Button Grid.Row="0" Grid.Column="8" Margin="5" BorderThickness="0" Background="Transparent">
                    <Image Source ="/Images/minus-sign.png" Height="16" Width="16" />
                    <i:Interaction.Triggers>
                        <i:EventTrigger EventName="Click">
                            <cal:ActionMessage MethodName="RemoveWorkPiece">
                                <cal:Parameter Value="{Binding Id}" />
                            </cal:ActionMessage>
                        </i:EventTrigger>
                    </i:Interaction.Triggers>
                </Button>
            </Grid>
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>

物业:

public BindingList<WorkPieceModel> WorkPieces
{
    get { return _workPieces; }
    set
    {
        _workPieces = value; NotifyOfPropertyChange(() => WorkPieces);
        NotifyOfPropertyChange(() => CanCalculate);
    }
}

更新显示名称和设置图标显示标志的后端函数:

private void UpdateWorkPiecesDisplayName()
{
    var counter = 1;
    foreach (var item in WorkPieces)
    {
        item.DisplayName = Roman.To(counter);
        item.IsLast = false;
        counter++;
    }

    WorkPieces.Last().IsLast = true;
    NotifyOfPropertyChange(() => WorkPieces);
}

因此,当我单击“添加/删除”时,它会正确更新元素的数量,但其余部分不会刷新按钮或 DisplayNumber。添加和移除工件后尝试调用 NotifyOfPropertyChange(),但没有任何预期结果。

目标是仅在最后一个元素上显示 + - 图标,在其余元素上显示 - 图标,并且显示的数字始终是升序的,无论哪个元素已被删除。

如您所见:IV。失踪和 III。有 + 图标(不应该有) 来自问题的图像

标签: c#wpfcaliburn.micro

解决方案


由于您绑定到IsLast,因此您应该INotifyPropertyChanged在类中实现接口WorkPieceModel并在 的 setter 中引发PropertyChanged事件IsLast


推荐阅读