Question

I’ve read this solution: How do I make a ListBox refresh its item text?

But I’m still having no luck getting the text displayed in the listBox to update when the object’s property changes.

public partial class Form1 : Form
{
    public BindingList<Channel> chanList = new BindingList<Channel>();

    private void Form1_Load(object sender, EventArgs e)
    {
        lbChannels.DisplayMember = "Display";
        lbChannels.DataSource = chanList;
    }

} 


public class Channel
{
    public string Display
    {
        get
        {
            return ToString();
        }
    }

    public override string ToString()
    {
        if(!unread || DateTime.Now.Second % 2 == 0)
            return Name;
        return "";
    }
}

The goal here is to cause the channel name to blink in the listBox if there’s unread data in it, but when I test it nothing happens. I’ve also tried calling lbChannels.Refresh() and lbChannels.Update().

I must be missing something but I can’t figure out what. The solution in the other thread seems almost too simple to be true, but I’ve looked through it several times and I can’t find anything else related to the listBox. What am I missing here?

Answer 1

The code is already written in the link you provided, do it the same way.. here’s an example for updating:

private void btnUpdate_Click(object sender, EventArgs e)
        {
            Employee selectedEmployee = (Employee)lstEmployees.SelectedItem;
            selectedEmployee.Name = "Joseph";
            if (selectedEmployee != null)
            {
                _employees[selectedEmployee.Id] =selectedEmployee;
            }
        }

Please do not bind to a Display function that uses a overriden ToString method that works if the Time in Seconds is even, that makes no sense.