CODEWITHSUNDEEP
c#.netwpfbinding
Mike Borozdin
Mike Borozdin

Reputation: 1188

WPF ComboBox SelectedItem Binding Doesn't Work

I have the following ComboBox that gets populat from an enum:

<ComboBox Name="cmbProductStatus" ItemsSource="{Binding Source={StaticResource statuses}}" 
                                                  SelectedItem="{Binding Path=Status}" />

Please, note that the DataContext gets set in code-behind.

It's not even about two-way binding, I have some default value for Product.Status but it never gets selected.

Updated

I was asked to put code of my Status property.

public class Product    {
    //some other propertties
    private ProductStatus _status = ProductStatus.NotYetShipped;
    public ProductStatus Status { get { return _status; } set { value = _status; } }
}

public enum ProductStatus { NotYetShipped, Shipped };

Upvotes: 0

Views: 4468

Answers (2)

zapico
zapico

Reputation: 2396

Your status property must notify its change and your Product class must implement INotifyPropertyChanged interface.

Here you have the MVVM Light code snippet for the property ;-)

/// <summary>
        /// The <see cref="MyProperty" /> property's name.
        /// </summary>
        public const string MyPropertyPropertyName = "MyProperty";

        private bool _myProperty = false;

        /// <summary>
        /// Gets the MyProperty property.
        /// TODO Update documentation:
        /// Changes to that property's value raise the PropertyChanged event. 
        /// This property's value is broadcasted by the Messenger's default instance when it changes.
        /// </summary>
        public bool MyProperty
        {
            get
            {
                return _myProperty;
            }

            set
            {
                if (_myProperty == value)
                {
                    return;
                }

                var oldValue = _myProperty;
                _myProperty = value;

                // Remove one of the two calls below
                throw new NotImplementedException();

                // Update bindings, no broadcast
                RaisePropertyChanged(MyPropertyPropertyName);

                // Update bindings and broadcast change using GalaSoft.MvvmLight.Messenging
                RaisePropertyChanged(MyPropertyPropertyName, oldValue, value, true);
            }
        }

Upvotes: 1

LueTm
LueTm

Reputation: 2380

ComboBox binding is a little tricky. Make sure that the itemssource is loaded when you assign the DataContext and that the item you assign with SelectedItem meets the == relation with one item in the ItemsSource.

Upvotes: 3

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