Similar to QQ, tray shows the icon when the program is minimized. Is a control, demo source code, there is a more detailed explanation, I just Delphi 7 environment used. See demo sounds simple, and absolutely available.

CoolTrayIcon（程序最小化时托盘显示插件）\CoolTrayIcon.dcr
........................................\CoolTrayIcon.dcu
........................................\CoolTrayIcon.html
........................................\CoolTrayIcon.pas
........................................\demos\CoolTrayIcon.dcu
........................................\.....\CoolTrayIcon.pas
........................................\.....\CoolTrayTest.cfg
........................................\.....\CoolTrayTest.dof
........................................\.....\CoolTrayTest.dpr
........................................\.....\CoolTrayTest.exe
........................................\.....\CoolTrayTest.res
........................................\.....\CtDraw.dfm
........................................\.....\CtDraw.pas
........................................\.....\CtMain.dcu
........................................\.....\CtMain.ddp
........................................\.....\CtMain.dfm
........................................\.....\CtMain.pas
........................................\.....\CtMain.~ddp
........................................\.....\CtMain.~dfm
........................................\.....\CtMain.~pas
........................................\.....\TextTrayTest.dpr
........................................\.....\TextTrayTest.exe
........................................\.....\TextTrayTest.res
........................................\.....\TrayDraw.dpr
........................................\.....\TrayDraw.exe
........................................\.....\TrayDraw.res
........................................\.....\TtMain.dfm
........................................\.....\TtMain.pas
........................................\History - CoolTrayIcon.txt
........................................\History - TextTrayIcon.txt
........................................\install.txt
........................................\readme.txt
........................................\TextTrayIcon.dcr
........................................\TextTrayIcon.html
........................................\TextTrayIcon.pas
........................................\TrayIcon.txt
........................................\demos
CoolTrayIcon（程序最小化时托盘显示插件）

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