Forcing a ListView to draw in the background

Question

I have a ListView which sometimes I need to put around 10000 items in. ListViews don't really handle this well, and they lock up for a couple of seconds while they sort the items and draw them. If you add the items in individually, it's even worse, locking up for nearly a minute.

To get around this, I thought I'd try populating the ListView before I need to display it, but unfortunately it has other ideas. It only starts drawing when I turn the panel that contains the ListView visible, making the program hang for a couple of seconds.

Any ideas for how I can eliminate this delay? Or is there another component that's relatively easy to use that is better at showing large quantities of data?

Answer 1

You need to use the VirtualMode.

Answer 2

Well. If you just want to load the content in the background you could try a thread to populate the ListView, which will let the form load.

I don't think you will get the pause if you put an Application.DoEvents(); when you are loading the items (which allows the form to redraw and receive events).

for (int ix=0; ix < 10000; ix ++)
{
 listView1.Items.Add(ix.ToString());
 Application.DoEvents();
}

I guess my suggestions are good if you aren't aware of VirtualMode