IInputMethod
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The software-based input panel creates the IM through the IInputMethod interface. After the IM is created, the IM receives user input and passes this data to the software-based input panel through the IIMCallback interface. After the software-based input panel receives data from the IM, the software-based input panel passes the data to the Graphics, Windowing, and Events Subsystem (GWES) module. Usually, this data is a keyboard event. GWES passes the message to your application through the standard delivery system for keyboard events. The following illustration shows how an IM, a software-based input panel, GWES, and an application communicate.