How to dynamically set glance icon?

Hi! I'm trying to change the icon of my glance dynamically, i.e. if the current weather is nice I'd like it to be the sun, if it's raining a bitmap of a rain cloud, etc.

I can see that there's a function in View called setIcon, but that doesn't work for GlanceView. I also know that it's possible because the standard calendar, weather etc. glances have dynamic icons. Can anyone give me a hint how to achieve this? Or is this not something that's possible with monkeyC?