Attaching ObservableCollection as ItemsSource of ItemsControl

问题

I have an object like so:

class RCLocation : INotifyPropertyChanged
{
    private string _id;
    private string _name;
    private bool _checked;

    public string Id { /* get/set with NotifyPropertyChanged() */ }
    public string Name  { /* get/set with NotifyPropertyChanged() */ }
    public bool Checked { /* get/set with NotifyPropertyChanged() */ }

    /* INotifyPropertyChanged implementation methods */
}

Now in my MainWindow.xaml I have an ItemsControl like so:

<ItemsControl Name="lstDropOff" ScrollViewer.VerticalScrollBarVisibility="Auto">
    <ItemsControl.ItemTemplate>
        <DataTemplate>
            <StackPanel Orientation="Horizontal">
                <CheckBox IsChecked="{Binding Checked, Mode=TwoWay}"/>
                <TextBlock Text="{Binding Name}"/>
            </StackPanel>
        </DataTemplate>
    </ItemsControl.ItemTemplate>
</ItemsControl>

I bind the data to this list in my code behind like so:

ObservableCollection<RCLocation> dropOffs = new ObservableCollection<RCLocation>();
lstDropOff.ItemsSource = dropOffs;
dropOffs.Add(new RCLocation { /* some data here */ });
dropOffs.Add(new RCLocation { /* some data here */ });
dropOffs.Add(new RCLocation { /* some data here */ });
dropOffs.Add(new RCLocation { /* some data here */ });

The items I have just added do not show in the ItemsControl. What exactly am I doing wrong? Can't figure it out :/
Thanks for help.

回答1:

You have not set the ItemsSource using a binding, which you need to do in order to involve the WPF binding engine and have the control react to data source changes.

Here's how to do that from code-behind:

// instead of lstDropOff.ItemsSource = dropOffs
var binding = new Binding() { Source = dropOffs };
lstDropOff.SetBinding(ItemsControl.ItemsSourceProperty, binding);

回答2:

Nothing wrong with your code, I tried using this... and show up on your xaml code

using PhoneApp4.Resources;
using System.ComponentModel;
using System.Collections.ObjectModel;
using Microsoft.Phone.Controls;

namespace PhoneApp4
{
    public partial class MainPage : PhoneApplicationPage
    {
        public MainPage()
        {
            InitializeComponent();

            ObservableCollection<RCLocation> dropOffs = new ObservableCollection<RCLocation>();
            lstDropOff.ItemsSource = dropOffs;
            dropOffs.Add(new RCLocation { Id = "1", Name = "Tester", Checked = true });
            dropOffs.Add(new RCLocation { Id = "1", Name = "Tester", Checked = true });
            dropOffs.Add(new RCLocation { Id = "1", Name = "Tester", Checked = true });
            dropOffs.Add(new RCLocation { Id = "1", Name = "Tester", Checked = true });
        }
    }

    class RCLocation 
    {
        private string _id;
        private string _name;
        private bool _checked;

        public string Id { get; set; }
        public string Name { get; set; }
        public bool Checked { get; set; }
    }
}

来源：https://stackoverflow.com/questions/19114190/attaching-observablecollection-as-itemssource-of-itemscontrol

标签

wpf

xaml

data-binding

observablecollection