Listview ItemSelectionChanged fires twice?

问题

I have a Winforms App in C# with a ListView control. This ListView shows a list of TO-DO items and I am using the 'ItemSelectionChanged' event to handle updates.

The problem is that the 'ItemSelectionChanged' event fires twice each time I try to make an update.

The ItemSelectionChanged event refreshs the form to represent the updates (ie remove item from list).

Is there a way to disable the event from firing after the refresh?

UPDATE1:

private void listView1_ItemSelectionChanged(object sender, ListViewItemSelectionChangedEventArgs e)
    {   
        if (e.IsSelected)
        {                
            listView1.Items[e.ItemIndex].Remove();

            listView1.SelectedIndices.Clear();
            listView1.Focus();

            listView1.Update();
        }
        else
        {

        }

    }

回答1:

Yes, it will fire twice. Once because the previously selected item became unselected, again for the newly selected item. You just have to make sure you see the selection event:

    private void listView1_ItemSelectionChanged(object sender, ListViewItemSelectionChangedEventArgs e) {
        if (e.IsSelected) {
            // Update form
            //...
        }
    }

回答2:

Yes just remove the EventHandler at the start of the refresh and add it again after it has finished refreshing

i.e

// Remove handler
listView1.ItemSelectionChanged -= new ListViewItemSelectionChangedEventHandler(listView1_ItemSelectionChanged);

// Do refresh

// Add again
listView1.ItemSelectionChanged += new ListViewItemSelectionChangedEventHandler(listView1_ItemSelectionChanged);

回答3:

I think you need manually unselect the item in the end of your handler.

listView1.SelectedItem = null;

回答4:

Try this:

private void ItemSelect()
{

        if(SelectedItem!=null)
            App.Current.MainPage.Navigation.PushAsync(new Pages.TLAccByCurrency(), true);
        _selectedItem = null;
}

来源：https://stackoverflow.com/questions/3229498/listview-itemselectionchanged-fires-twice

标签

winforms

events

.net-3.5

listview