NotifyIcon and High DPI Displays

2
votes

Following this guide: http://www.hhhh.org/cloister/csharp/icons/ I was able to get my NotifyIcon to look the way it should because Windows decides to use the 32x32 icon and scale it to a 16x16 instead of just using the 16x16 icon.

That being said, I have an .ico file with the following resolutions:

  • 256x256x32
  • 64x64x32
  • 48x48x32
  • 32x32x32
  • 16x16x32
  • 48x48x8
  • 32x32x8
  • 16x16x8
  • 32x32x4
  • 16x16x4

However, when I increase the DPI settings on my display, the icon displayed in the NotifyIcon is a higher resolution version, with more embellishments that end up looking terrible scaled to the size of the NotifyIcon. What size icon is it taking and scaling now? Would I be better off just creating a simple icon of every size specifically for the NotifyIcon?

3
c#winformsiconsdpisystem-tray

3 Answers

0
votes

The icons displayed in the notification area are small icons. That is their size is given by the SM_CXSMICON system metric. Find out that size and supply an icon of the exact dimensions to avoid aliasing. If you have not got one the exact size to hand, probably the best you can do is to draw the closest smaller sized icon onto the middle of an empty transparent canvas, and use that.

You may not be able to do this using the managed NotifyIcon wrapper. I expect that you don't get enough control. The procedure I describe really requires you to be able to call Shell_NotifyIcon, the native API, and pass an HICON.

0
votes

This page http://msdn.microsoft.com/en-us/library/bb773352(VS.85).aspx gives an example of how to pass the correct icon for the correct DPI. It uses LoadIconMetric, which probably isn't directly available in c#, but it would be simple to marshal one.

0
votes

Check my answer here: notifyicon image looks terrible once image ends up in system tray

Basically, you need to explicitly declare which size to use at runtime, and to declare your app as DPI-Aware.