Question

我在几页上搜索过并找到了几篇关于这个主题的文章，但我似乎仍然无法知道遗漏了什么。我的代码只显示第一个列表框的条目。当我单击它时，我从数据库中获取数据，但是第二个列表框中没有显示任何内容。（顺便说一下，我使用PRISM框架）。有人能给我一个暗示吗？

XAML：

<ListBox ItemsSource="{Binding GroupList}" SelectedItem="{Binding SelectedGroup}" SelectedValue="ID" DisplayMemberPath="BEZ" HorizontalAlignment="Left"/>

<ListBox ItemsSource="{Binding FoodList}" DisplayMemberPath="BEZ"/>

我的观点模型：

public class FoodViewModel : BindableBase
{
    private FOODGROUP _selectedGroup;
    public FOODGROUP SelectedGroup
    {
        get { return this._selectedGroup; }
        set
        {
            SetProperty(ref this._selectedGroup, value);
            GetFoodByGroup(SelectedGroup.ID);
        }
    }

    public ObservableCollection<FOODGROUP> GroupList { get; set; }
    public ObservableCollection<FOOD> FoodList{ get; set; }

    public FoodViewModel()
    {
        GroupList = new ObservableCollection<FOODGROUP>(FoodController.GetGroups());
    }

    private void GetFoodByGroup(long groupId)
    {
        FoodList = new ObservableCollection<FOOD>(FoodController.GetFoodList(groupId));
    }
}

Answer 1

替换此行：

public ObservableCollection<FOOD> FoodList{ get; set; }

通过这个

private ObservableCollection<FOOD> _foodList;
public ObservableCollection<FOOD> FoodList
{
    get 
    { 
        return _foodList;
    }
    set
    { 
        SetProperty(ref this._foodList, value);
    } 
}

级联列表框

1 个答案: