Selected Item in ComboBox wpf with Binding

Question

I have a listview, when selecting the listview I make a binding to an SelectedCategory property.

When binding to Checkbox, Textbox an so works fine, but I can't find the right combination for the ComboBox no matter what I try.

I know for sure, that the ProjectName exists AND is binded correctly to the SelectedCategory (I have made a button and before that display the ProjectId and ProjectName).

I hope one of You can see, where I'm doing something wrong

Best regards
Simsen :-)

My ListView looks like this

And here I show you a Checkbox witch works perfectly
HorizontalContentAlignment="Left" Grid.ColumnSpan="2"
IsChecked="{Binding ElementName=LivCategories, Path = SelectedValue.CategoryIsObsolete, Mode = TwoWay}" />

One of the ways I have tried for the ComboBox you can see here
ItemsSource="{Binding Path=Projects_GetActive}" DisplayMemberPath="ProjectName"
SelectedValuePath="LivCategories"
SelectedItem="{Binding ElementName=LivCategories, Path= SelectedValue.ProjectName, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" IsSynchronizedWithCurrentItem="True">

And here You can see the SelectedCategory

private Category _selectedCategory;
        public MyICommand DeleteCommand { get; set; }

        public Category SelectedCategory
        {
            get
            {
                return _selectedCategory;
            }

            set
            {
                _selectedCategory = value;
                DeleteCommand.RaiseCanExecuteChanged();
            }
        }

Accepted Answer

Hi,
if you want select Project in ComboBox bind Text property like in following demo:

XAML:

And classes:

using System.Collections.ObjectModel;  
using System.ComponentModel;  
using System.Windows;  
using System.Windows.Data;  
       
namespace WpfApp035  
{  
  public class ViewModel  
  {  
    public ViewModel()  
    {  
      ObservableCollection colCA = new ObservableCollection();  
      colCA.Add(new Category() { CategoryId = 1, CategoryIsGlobal = true, CategoryIsObsolete=false, CategoryName = "Cat 1", ProjectId = 11, ProjectName = "Project 11" });  
      colCA.Add(new Category() { CategoryId = 2, CategoryIsGlobal = false, CategoryIsObsolete = false, CategoryName = "Cat 2", ProjectId = 12, ProjectName = "Project 12" });  
      colCA.Add(new Category() { CategoryId = 3, CategoryIsGlobal = true, CategoryIsObsolete = false, CategoryName = "Cat 3", ProjectId = 13, ProjectName = "Project 13" });  
      colCA.Add(new Category() { CategoryId = 4, CategoryIsGlobal = false, CategoryIsObsolete = true, CategoryName = "Cat 4", ProjectId = 14, ProjectName = "Project 14" });  
      colCA.Add(new Category() { CategoryId = 5, CategoryIsGlobal = true, CategoryIsObsolete = false, CategoryName = "Cat 5", ProjectId = 15, ProjectName = "Project 15" });  
      cvsCA.Source = colCA;  
      //  
      ObservableCollection colPA = new ObservableCollection();  
      colPA.Add(new Project() { ProjectName = "Project 11" });  
      colPA.Add(new Project() { ProjectName = "Project 12" });  
      colPA.Add(new Project() { ProjectName = "Project 13" });  
      colPA.Add(new Project() { ProjectName = "Project 14" });  
      colPA.Add(new Project() { ProjectName = "Project 15" });  
      cvsPA.Source = colPA;  
    }  
    private CollectionViewSource cvsCA = new CollectionViewSource();  
    public ICollectionView Categories_GetActive { get => cvsCA.View; }  
    public Category SelectedCategory { get; set; }  
    private CollectionViewSource cvsPA = new CollectionViewSource();  
    public ICollectionView Projects_GetActive { get => cvsPA.View; }  
  }  
  
  public class Category  
  {  
    public int CategoryId { get; set; }  
    public string CategoryName { get; set; }  
    public bool CategoryIsGlobal { get; set; }  
    public string ProjectName { get; set; }  
    public int ProjectId { get; set; }  
    public bool CategoryIsObsolete { get; set; }  
  }  
  
  public class Project  
  {  
    public string ProjectName { get; set; }  
  }  
}

Result:

Answer

I don't know the details of your classes, so I created test classes for binding. I use a Enum and custom class to bind data for two ComboBoxs in ListView for you. Please check and let me know if you have any question.
Add xmlns:sys="clr-namespace:System;assembly=mscorlib" in Xaml:

The cs code is:

public partial class MainWindow : Window  
    {  
        public MainWindow()  
        {  
            InitializeComponent();  
            initList();  
        }  
        public void initList()  
        {  
            List Ltselecteds = new List(){  
            new testSelected() { Name = "SelName1",Value = "Value1"},  
            new testSelected() { Name = "SelName2",Value = "Value2"},  
            new testSelected() { Name = "SelName3",Value = "Value3"}  
            };  
  
  
            List listBook = new List();  
            for (int i = 0; i < 15; i++)  
            {  
                if (i / 2 == 0)  
                {  
                    listBook.Add(new MyModel()  
                    {  
                        testSelecteds =Ltselecteds,  
                        CategoryId = "00" + i.ToString(),  
                        CategoryName = "testBook" + i,  
                        CategoryIsGlobal = "Math",  
                        ProjectName = "qiaobus",  
                        ProjectId = "pid" + i.ToString(),  
                        SelectedCat = SelectedCategory.Category1  
                    });  
  
                }  
                else  
                {  
                    listBook.Add(new MyModel()  
                    {  
                        testSelecteds =Ltselecteds,  
                        CategoryId = "00" + i.ToString(),  
                        CategoryName = "testBook" + i,  
                        CategoryIsGlobal = "Math",  
                        ProjectName = "qiaobus",  
                        ProjectId = "pid" + i.ToString(),  
                        SelectedCat = SelectedCategory.Category2  
                    });  
  
                }  
            }  
            listView1.ItemsSource = listBook;  
        }  
    }  
    public class MyModel  
    {  
        public string CategoryId { get; set; }  
        public string CategoryName { get; set; }  
        public string CategoryIsGlobal { get; set; }  
        public string ProjectName { get; set; }  
        public string ProjectId { get; set; }  
        public SelectedCategory SelectedCat { get; set; }  
  
        public List testSelecteds { get; set; } = new List();  
  
    }  
  
    public enum SelectedCategory { Category1, Category2, Category3 }  
  
    public class testSelected  
    {  
        public string Name { get; set; }  
        public string Value { get; set; }  
    }

The result picture is:

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Answer

Hi Thank you for your answer.

I'm so sorry that I haven't been clear enough.

I have a ListView, that shows the active Category list. I also have some controls. These controls should show the values from the selected row in the ListView.

That works fine except from the control combobox. I have made a a SelectedCategory in the CategoryViewModel, and it shows the selected value for the row I have selected.

I populate the combobox with a list of Projects. But when selecting a row in the ListView it doesn't show the specific Project in the comboBox.

I'm unsure if it is because that the ProjectId is a foreign key in the Category list?

I'm pretty sure, it hasn't anything with the code behind because I have made to textboxes to be sure, I get the selected values for the selected row in the ListView - and these shows the correct projectId and projectName. So it has to do with this specifc line - I don't get it right;

I have tried your 2 suggestions and with no success
This doesn't do anything with the combobox. It shows correctly the 4 rows but when clicking on a specific row it doesn't show the specific Project.

This one gets me an error " The resource could not be resolved.

Here I have made 2 textboxes (which shows the correct projectid and projectName when activating the row in the listview;

And the combobox that dos not change anything.

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Selected Item in ComboBox wpf with Binding

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