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WPF combobox is empty when binding enum

I am trying to bind values of an enum to a combo box but the combo box remain empty with no options to choose.
This is the combo box xaml defintion:
<ComboBox Grid.Row="2" Grid.Column="1" ItemsSource="{Binding Path=SkillItemSource}" SelectedItem="{Binding Path=neededSkill, Mode=TwoWay}" SelectedIndex="0" Margin="5" MinWidth="100"></ComboBox>
And this is the items source and selected item which are defined in the window's cs:
public Skill neededSkill = Skill.FirstSkill;
public string[] SkillItemSource
{
get
{
return Enum.GetNames(typeof(Skill));
}
}
What is missing for the values to appear in the combobox?

What is missing for the values to appear in the combobox?
You need to set the DataContext of the ComboBox, or a parent element, to an instance of the class where the SkillItemSource property is defined. If the property is defined in the code-behind, you could just set the DataContext to the view itself: this.DataContext = this;
Also, you can't mix types. If the ItemsSource is bound to an IEnumerable<string>, the SelectedItem property should be bound to a string property.
Also note that neededSkill must be defined as a public property for you to be able to bind to it.
Try this:
public Skill neededSkill { get; set; } = Skill.FirstSkill;
public IEnumerable<Skill> SkillItemSource { get; } = Enum.GetValues(typeof(Skill)).Cast<Skill>();

Populate RadComboBox from enum list in WPF MVVM

I found some topics "How to bind a combobox from enum list", but my problem is that I try to use MVVM arhitecture and let my View (xaml) clear as you see below:
part of View (xaml.cs):
public partial class GreenCertificatesStockForm : Erp.Core.Wpf.BaseWindow
{
private Models.GreenCertificatesGroupModel model;
public GreenCertificatesStockForm()
{
model = new Models.GreenCertificatesGroupModel();
this.DataContext = model;
InitializeComponent();
model.LoadForm(); // propose some dates for my form
model.RequestClose += () => { Close(); };
}
}
part of View (xaml) my RadComboBox:
<telerik:RadComboBox Name="certificatesTypeRadComboBox"
Margin="5 2 0 2" Width="150"
SelectedValue="{Binding CertificatesTypeEnum , Mode=TwoWay,
ValidatesOnDataErrors=True,
ValidatesOnExceptions=True,
NotifyOnValidationError=True}"
ItemSource="{Binding }"
SelectedItem="{Binding }"
telerik:StyleManager.Theme="Office_Blue" BorderBrush="#FF707070" Background="#FFDDDDDD"
>
</telerik:RadComboBox>
So, my Enum list is created in my ViewModel (class.cs) as:
public enum CertificatesTypeEnum {
Estimat = 1,
Calculat = 2,
Facturat = 3
}
I need to display in my RadComboBox all Values of the Enum and by selectedValue to save the specific Key of selection in DB (this with a parameter). How can I display the values from ViewModel into ComboBox (View)?
I know can do something like :
var items = Enum.GetValues(typeof(CertificatesTypeEnum)).Cast<CertificatesTypeEnum>().Select(i => new ComboboxItem()
{ Text = Enum.GetName(typeof(gender), i), Value = (int)i}).ToArray<ComboboxItem>();
//Add the items to your combobox (given that it's called comboBox1)
RadComboBoxName.Items.AddRange(items);
but this must be made in xaml.cs file (and I don't want this solution), because in ViewModel the combobox are not recognised and will be not found.
In short : display Values of Enum list from ViewModel class in xaml file.

Why don't you just call the Enum.GetValues method in the view model? This is MVVM:
public class GreenCertificatesGroupModel
{
public IEnumerable<CertificatesTypeEnum> EnumValues
{
get
{
var list = Enum.GetValues(typeof(CertificatesTypeEnum)).Cast<CertificatesTypeEnum>();
return list;
}
}
private CertificatesTypeEnum _selectedItem;
public CertificatesTypeEnum SelectedItem
{
get { return _selectedItem; }
set { _selectedItem = value; }
}
}
XAML:
<telerik:RadComboBox ItemsSource="{Binding EnumValues}" SelectedItem="{Binding SelectedItem, Mode=TwoWay}" />

How to pass data from DataContext to ListBox in WPF?

I have a class defined like:
public class Agent
{
public int Id { get; set; }
public string Category { get; set; }
// rest removed for brevity
}
Then, in WPF, I get the data as List and pass it to DataContext as this:
List<Agent> agents; // this includes my data
this.DataContext = agents;
And in .xaml part I want to list the Category field of each object. I have something like this:
<ListBox
Name="agentCategoryListBox"
Grid.Row="2"
Grid.Column="1"
ItemSource="{Binding Path=Category"} />
But this doesn't seem to work correctly. Any ideas?

Let me help you to do this in the correct way as Alex suggested.
Create a list and populate it in ViewModel like this
ViewModel
public class MainWindowViewModel : INotifyPropertyChanged
{
public MainWindowViewModel()
{
agents = new ObservableCollection<Agent>();
LoadData();
}
private void LoadData()
{
agents.Add(new Agent { Id = 1, Category = "a" });
agents.Add(new Agent { Id = 2, Category = "b" });
agents.Add(new Agent { Id = 3, Category = "c" });
}
}
In XAML, Make your list and use data template like this:
<Window.Resources>
<DataTemplate x:Key="AItemTemplate">
<TextBlock Text="{Binding Category}"></TextBlock>
</DataTemplate>
</Window.Resources>
<ListBox ItemsSource="{Binding agents}"
ItemTemplate="{StaticResource AItemTemplate}"></ListBox>
That is it !!

Normally the DataContext would be a view model class that would contain the list of agents; then you can bind the ItemsSource to that list. Any of the many examples that deal with listbox will be pretty straight forward when it comes to that. Not really sure how the binding should look like if the list itself is the DataContext.
Then once the ItemsSource is set to a list of agents, if you want to show the Category in the list, the simpler way is to set DisplayMemberPath to "Category".
I suggest looking into MVVM and learning to apply it, it's an invaluable concept in my opinion.

You try to bind your listbox to a string property.
You can try this :
Give a name to your user control for exemle myUC
Add a property to your user control :
public List<Agent> AgentList { get; set; };
Fill your agentlist :
this.AgentList = //fill method
And bind your listbox like this :
<ListBox
Name="agentCategoryListBox"
Grid.Row="2"
Grid.Column="1"
ItemSource="{Binding Path=AgentList, ElementName=myUC"} />

may be this will give you an idea:
http://www.c-sharpcorner.com/forums/wpf-datacontext-binding-with-listbox

The fastest way to get what you want is :
<ListBox
Name="agentCategoryListBox"
Grid.Row="2"
DisplayMemberPath="Category"
Grid.Column="1"
ItemSource="{Binding Path=."} />
ItemsSource is binded directly to your Datacontext (which is your list) And then you tell to your ListBox to display the property Category.
But the proper way would have been :
1 - Create a DataContext
public class AgentsDC
{
public List<Agent> Agents { get; set; }
}
2 - Give this class as DataContext
this.DataContext = new AgentsDC();
3 - Bind all these things
<ListBox
Name="agentCategoryListBox"
Grid.Row="2"
DisplayMemberPath="Category"
Grid.Column="1"
ItemSource="{Binding Path=Agents"} />

I also would suggest you to use MVVM. But if you do not want to then try this.
XAML:
<ListBox Name="AgentCategoryListBox" ItemsSource="{Binding}">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Category}" d:DataContext="{d:DesignData}" />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
CS:
public MainWindow()
{
InitializeComponent();
List<Agent> agents = new List<Agent>
{
new Agent
{
Category = "Category"
}
};
DataContext = agents;
}
public class Agent
{
public string Category
{
get;
set;
}
}

WPF XAML Binding List and Combobox

I am teaching myself how to bind classes to XAML objects. I can't find anything on data within lists. Either that or I don't know the terminology very well. I want to make a combobox that is tied to the list, displaying the name of each Item in the Items list. How would I bind this to the combobox?
class Section
{
List<Item> Items = new List<Item>();
}
class Item
{
private string _name;
public string Name
{
get { return _name; }
set { _name = value; }
}
}

Try This,
<ComboBox ItemsSource="{Binding Items}" DisplayMemberPath="Name" />
Make your Items collection as a property.
public List<Item> Items { get; set;}
Section Class should be public and make it as your DataContext

Assuming Section is the current DataContext :
<ComboBox ItemsSource="{Binding Items}"
DisplayMemberPath="Name" />

Getting SelectedItem of ComboBox (MVVM)

I'd like to get the selected Item of a ComboBox using the MVVM Pattern (beginner).
I've read that this could be achieved by binding the SelectedItem Property to a Property in the ViewModel.
XAML:
<ComboBox ItemsSource="{Binding RoomLockerLinkCollection}"
DisplayMemberPath="Room.Name"
SelectedItem="{Binding SelectedRoom}"/>
ViewModel:
public Room SelectedRoom { get; set; }
But it's not working - the only thing thats happening is a appearing red border around that ComboBox - in addition after selecting a new item in the ComboBox the "SelectedRoom" property in my VM is still null.
Edit 1 :
One short additional question:
The binding works fine - at least for the top "category". My Wrapper-Class also contains a list of lockers.
<ComboBox DataContext="{Binding SelectedItem, ElementName=_cmbRoomSelection}" ItemsSource=" {Binding LockerCollection}" DisplayMemberPath="Name" SelectedValue="{Binding SAVM.SelectedLocker, Mode=TwoWay}" />
When I check the type of the SelectedValue it's a "Locker" - fine.
But the SelectedLocker-Property in my VM stays null...
Additional, could s.o. explain when to use "SelectedItem" and "SelectedValue"? What's the difference? Setting the DataContext in the xaml code above can not be done by binding the SelectedValue...
Edit 2 (Solution) :
Okay, got it!
As I figured out I've reset my DataContext - now the Property SAVM of course could not be found.
Solution:
<ComboBox DataContext="{Binding SelectedItem, ElementName=_cmbRoomSelection}"
ItemsSource="{Binding LockerCollection}"
DisplayMemberPath="Name"
SelectedValue="{Binding SAVM.SelectedLocker **ElementName=_vStorage**, Mode=TwoWay}" />

The red box is an indication of a validation error from your Binding ,
The most common error would be that the BindingSource and the BindingTarget are not of the same type.
Use SelectedValue and SelectedValuePath to bind to your Room object.
CS :
public class Room
{
public string RoomName { get; set; }
}
public class RoomWrapper
{
public Room Room { get; set; }
}
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.DataContext = this;
}
public List<RoomWrapper> RoomWrappers
{
get
{
var list = new List<RoomWrapper>();
for (int i = 0; i < 10; i++)
{
list.Add(new RoomWrapper { Room = new Room { RoomName = "Room " + i } });
}
return list;
}
}
private Room selectedRoom;
public Room SelectedRoom
{
get { return selectedRoom; }
set
{
selectedRoom = value;
}
}
XAML :
<ComboBox ItemsSource="{Binding RoomWrappers}"
DisplayMemberPath="Room.RoomName"
SelectedValuePath="Room"
SelectedValue="{Binding SelectedRoom, Mode=TwoWay}" />