所选项目ComboBox没有显示正确的ID WPF

问题描述

我有一个无法解决的问题。

Shellviewmodel

    private IEventAggregator _events;
    private SimpleContainer _container;

    public Shellviewmodel(IEventAggregator events,SimpleContainer container)
    {
       
        _events = events;
        _events.Subscribe(this);
        _container = container;

    void IHandle<CorrectionEvent>.Handle(CorrectionEvent message)
    {
         ActivateItem(_container.GetInstance<Correctionviewmodel>());
    }

Menuviewmodel

    private IEventAggregator _events;
    private Iusermodel _usermodel;
    private IDModel _selectOdprto;

    public BindableCollection<IDModel> Odprto { get; set; }

    public Menuviewmodel(IEventAggregator events,Iusermodel usermodel)
    {
        _events = events;
        _usermodel = usermodel;

        Task.Run(() => Data());        
    }

    public async Task Data()
    {
        DataAccessLibrary da = new DataAccessLibrary();
        Odprto = new BindableCollection<IDModel>(await da.GetData(_usermodel.UserName,"Odprto"));
    }

    public IDModel SelectOdprto
    {
        get { return _selectOdprto; }
        set
        {
            _selectOdprto = value;

            _events.PublishOnUIThread(new CorrectionEvent());
            _events.PublishOnUIThread(new IDEvent(_selectOdprto.ID,_selectOdprto));
        }
    }

Correctionviewmodel

    private IDModel _selectedID;
    private IDataAccess _dataAccess;
    private IEventAggregator _events;
    private Iusermodel _usermodel;

    public int IDOdprto { get; set; }
    public BindableCollection<IDModel> IDs { get; set; }

    public  Correctionviewmodel(IDataAccess dataAccess,IEventAggregator events,Iusermodel usermodel)
    {
        _dataAccess = dataAccess;
        _usermodel = usermodel;

        Task.Run(() => Data());

        _events = events;
        _events.Subscribe(this);
    }

    public async Task Data()
    {
        DataAccessLibrary da = new DataAccessLibrary();
        IDs = new BindableCollection<IDModel>(await da.GetData(_usermodel.UserName,"Odprto")); 
        NotifyOfPropertyChange(() => IDs);          
    }

    public IDModel SelectedID
    {
        get { return _selectedID; }
        set
        {
        SelectedID = message.IDModel;
        SelectedID.ID = message.IDMenu;
        NotifyOfPropertyChange(() => SelectedID);   
        }
     }



    public void Handle(IDEvent message)
    {
        _selectedID= message.IDModel;
        NotifyOfPropertyChange(() => SelectedID);
    }

IDModel库

public class IDModel
{
    public int ID { get; set; }
    public string IZVOR { get; set; }
}

IDEvent

public class IDEvent
{
    public IDEvent(int _IDMenu,IDModel T)
    {
        IDMenu = _IDMenu;
        IDModel = T;
    }

    public int IDMenu { get; private set; }
    public IDModel IDModel { get; private set; }
}

更正XAML

    <ComboBox Grid.Column="1" Grid.Row="1" IsSynchronizedWithCurrentItem="True"
              ItemsSource="{Binding IDs}"  MinWidth="200"
              SelectedItem="{Binding SelectedID,Mode=TwoWay}" Margin="5"
              HorizontalAlignment="Left" materialDesign:HintAssist.Hint="Izberite ID"
              Style="{StaticResource MaterialDesignFloatingHintComboBox}" >

        <ComboBox.ItemTemplate>
            <DataTemplate>
                <ComboBoxItem Content="{Binding ID}" HorizontalAlignment="Center" />
            </DataTemplate>
        </ComboBox.ItemTemplate>
    </ComboBox>

菜单XAML

    <ListBox Grid.Row="2" Grid.Column="1" Grid.ColumnSpan="2" Grid.RowSpan="2" MinHeight="200" 
              MinWidth="200" MaxHeight="300" ItemsSource="{Binding Odprto}" HorizontalAlignment="Left"
              BorderBrush="Black" BorderThickness="1" Margin="10" SelectedItem="{Binding SelectOdprto}">
        <ListBox.ItemTemplate>
            <DataTemplate>
                <TextBlock Text="{Binding ID}" />
            </DataTemplate>
        </ListBox.ItemTemplate>
    </ListBox>

因此代码可以工作，但是问题是ComboBox显示的是第一项，而不是随事件传递的项。其他TextBlocks显示正确的值，如果执行MessageBox.Show（SelectedID.ID.ToString（））;值正确，只是ComboBox显示错误的项目。

解决方法

这些方法看起来坏了，让我们修复

public IDModel SelectedID
{
    get => _selectedID;
    set
    {
        _selectedID = value;
        NotifyOfPropertyChange(() => SelectedID);   
    }
}

public void Handle(IDEvent message)
{
    SelectedID = IDs?.FirstOrDefault(x => x.ID == message.IDModel.ID);
}