Caliburn Micro - 在选项卡控件上显示名称 - 初学者问题

Question

参考文献

Github 项目CMTabNavigation

TargetFramework netcoreapp3.0

PackageReference Caliburn.Micro Version="4.0.105-alpha"

当用户单击菜单项时，我正在做我的第一个示例以在选项卡控件中显示 ViewModel。 该示例工作正常，但选项卡上的显示名称不起作用。你能帮我吗

<Window x:Class="CMTabNav.Views.ShellView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:cal="http://www.caliburnproject.org"
        xmlns:local="clr-namespace:CMTabNav.Views"
        mc:Ignorable="d"
        Title="ShellView" Height="450" Width="800">
    <DockPanel>
        <Menu DockPanel.Dock="Top" FontSize="25">
            <MenuItem Header="_File">
                <MenuItem.Background>
                    <RadialGradientBrush>
                        <GradientStop Color="Black" Offset="0"/>
                        <GradientStop Color="#FFC3C1AD" Offset="0.105"/>
                    </RadialGradientBrush>
                </MenuItem.Background>
                <MenuItem x:Name="PartsList" Header="_Parts List" />
                <MenuItem x:Name="AssembliesList" Header="_Assembly List" />
                <MenuItem x:Name="Demo" Header="_Demo" />
                <MenuItem x:Name="ExitApplication" Header="_Exit" />
            </MenuItem>

        </Menu>
        <Grid>
            <TabControl x:Name="Items">
                <TabControl.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Orientation="Horizontal">
                            <TextBlock Text="{Binding DisplayName}" />
                            <Button Content="X"  
                                cal:Message.Attach="DeactivateItemAndTryClose($dataContext, 'true')" />

                        </StackPanel>

                    </DataTemplate>
                </TabControl.ItemTemplate>
            </TabControl>


            <!--<ContentControl x:Name="ActiveItem" Margin="20 5 20 20">

            </ContentControl>-->
        </Grid>
    </DockPanel>
</Window>

ShellViewModel.cs

using Caliburn.Micro;
using System;
using System.Collections.Generic;
using System.Text;
using System.Threading;

namespace CMTabNav.ViewModels
{
    public class ShellViewModel : Conductor<object>.Collection.OneActive
    {
        public ShellViewModel()
        {

        }

        public void PartsList()
        {

            ActivateItemAsync(IoC.Get<PartsListViewModel>(), new CancellationToken());
             DisplayName = "Part List";

        }
        public void AssembliesList() //AssembliesList
        {
            ActivateItemAsync(IoC.Get<AssembliesListViewModel>(), new CancellationToken());
            DisplayName = "Assembly List";
        }
        public void Demo()
        {
            ActivateItemAsync(IoC.Get<DemoViewModel>(), new CancellationToken());
            DisplayName = "Demo View";
        }
        public async Task DeactivateItemAndTryClose(IScreen item, bool close)
        {
            await DeactivateItemAsync(item, close, new CancellationToken());
        }


    }
}

PartsListViewModel.cs

using Caliburn.Micro;
using System;
using System.Collections.Generic;
using System.Text;

namespace CMTabNav.ViewModels
{
    class PartsListViewModel: Screen
    {
    }
}

Answer 1

您可以更改视图模型以继承PropertyChangedBase 类并实现IHaveDisplayName 接口，如下所示

class PartsListViewModel : PropertyChangedBase, IHaveDisplayName
{
    public string DisplayName { get; set; }
}

根据您的数据模板，DisplayName 应在选项卡项本身的数据上下文中声明（PartsListViewModel、DemoViewModel 等），而不是在ShellViewModel。您应该在激活任何视图模型之前设置显示名称

public void PartsList()
{
    var partsListViewModel = IoC.Get<PartsListViewModel>();
    partsListViewModel.DisplayName = "Part List";
    ActivateItemAsync(partsListViewModel, new CancellationToken());
}

您还应该更新DeactivateItemAndTryClose 方法并传递不同的类型参数而不是IScreen

public async Task DeactivateItemAndTryClose(PropertyChangedBase item, bool close)
{
    await DeactivateItemAsync(item, close, new CancellationToken());
}

但是，您可以保留视图模型，继承 Screen 类，只在激活之前为每个视图模型正确设置 DisplayName，如上面的 PartsList() 方法所示