Redraw balloon tip and tooltip in C#?

I wrote a C# application that is a simple countdown timer. I use it myself to keep track of cooking time (not to forget about boiling pasta) and other purposes.

It works in the tray. When hovering the icon it shows remaining time as a tooltip. When clicked it shows remaining time in a balloon tip. I would like displayed time to be "ticking down", i.e. to update every second.

How do I force update/redraw 开发者_如何学JAVAof the balloon and tool tip?

EDIT: I don't need to redraw the balloon itself. I only need time to be changing. In some sense I want to invalidate the balloon window, so that Windows will read text stored in BalloonText property and redraw it.

As you may have surmised by now, the tooltip is displayed on mouse-over, and its content is static.

Your best bet might be to use an Outlook-Style notification window, as described in this article. You will have much better control over your displayed content.