How to display text in system tray icon with win32 API?

Question

Trying to create a small monitor application that displays current internet usage as percentage in system tray in C using win32 API.

Also wanting to use colour backgrou

Answer 1

By text you mean "Tips" ?

Assuming you have your icon on the System Tray

NOTIFYICONDATA _stNotifyIconData;

// For a simple Tip
_stNotifyIconData.uFlags = NIF_TIP;
strcpy_s(_stNotifyIconData.szTip, "Little Tip"); // Copy Tip    
Shell_NotifyIcon(NIM_MODIFY, &_stNotifyIconData);

// For a Ballon Tip
_stNotifyIconData.uFlags = NIF_INFO;
strcpy_s(_stNotifyIconData.szInfoTitle, "Title of the Ballon"); // Title
strcpy_s(_stNotifyIconData.szInfo, "Text..." ); // Copy Tip
_stNotifyIconData.uTimeout = 3000;  // 3 Seconds
_stNotifyIconData.dwInfoFlags = NIIF_INFO;

Shell_NotifyIcon(NIM_MODIFY, &_stNotifyIconData);