How to change the keyboard input language from your application
Hot Virtual Keyboard shows the current input language.
Method 1
You can change the input language using the Windows message WM_INPUTLANGCHANGEREQUEST:
SendMessage(GetForegroundWindow, WM_INPUTLANGCHANGEREQUEST, 0, NewHKL);
Method 2
You can change the current system language using the /CHANGELANGUAGE command line parameter:
HVK.EXE /CHANGELANGUAGE 0409
Language Codes:
English (EN) - 0409
German (DE) - 0407
Spain (ES) - 040A
French (FR) - 040C
Russian (RU) - 0419
Here you can find all language codes: http://msdn2.microsoft.com/en-us/library/ms776294(VS.85).aspx
If you use this parameter without specifying an input language code, the program will switch the input language or layout to the next one:
HVK.EXE /CHANGELANGUAGE
Method 3
If you are writing kiosk software for a web browser, you can use the special JavaScript functions to control the on-screen keyboard. Launch Hot Virtual Keyboard and try these buttons: