How can I make the progress bar update fast enough?

Question

I\'m using a progress bar to show the user how far along the process is. It has 17 steps, and it can take anywhere from ~5 seconds to two or three minutes depending on the weath

Answer 1

Try invoking the call to the waiting.setProgess() method since waiting seems to live in another thread and this would be a classic cross thread call (which the compiler warns you about if you let him).

Since Control.Invoke is a bit clumsy to use I usually use an extension method that allows me to pass a lambda expression:

waiting.ThreadSafeInvoke(() => waiting.setProgress(...));

.

// also see http://stackoverflow.com/questions/788828/invoke-from-different-thread
public static class ControlExtension
{
    public static void ThreadSafeInvoke(this Control control, MethodInvoker method)
    {
        if (control != null)
        {
            if (control.InvokeRequired)
            {
                control.Invoke(method);
            }
            else
            {
                method.Invoke();
            }
        }
    }
}

Answer 2

Vista introduced an animation effect when updating the progress bar - it tries to smoothly scroll from the previous position to the newly-set position, which creates a nasty time lag in the update of the control. The lag is most noticeable when you jump a progress bar in large increments, say from 25% to 50% in one jump.

As another poster pointed out, you can disable the Vista theme for the progress bar and it will then mimic the behavior of XP progress bars.

I have found another workaround: if you set the progress bar backwards, it will immediately paint to this location. So, if you want to jump from 25% to 50%, you would use the (admittedly hackish) logic:

progressbar.Value = 50;
progressbar.Value = 49;
progressbar.Value = 50;

I know, I know - it's a silly hack - but it does work!

Answer 3

I have the same problem. I have a form with multiple progress bars (top one is for example file x/n, bottom one is task y/m) The top progress bar does not update TIMELY while the bottom one does Programatically I update it, invalidate, explicit process message, refresh or sleep does not fix it. Funny thing is that bottom progress bar and other component (time elapsed text) updates fine. This is purely a Vista+theme problem (animations like previously suggested, XP or Vista with classic theme works fine. When displaying a message box after the top progress bar has travelled to 100 (programmatically, not visually) I first see the message box and then I see the progress completing

I found that SetWindowTheme(ProgressBar.Handle, ' ', ' '); as explained on Disabling progress bar animation on Vista Aero works (but I have old style progress bars now)