IM Module

The following figure describes the position of IM module.

• KBD DD generates KBD event and pass the KBD event to PMWIN.
  
• PMWIN pass KBD event to IM. PMWIN notifies some events (focus change, codepage change, etc.) to IM.
  
• IM pass KBD event to IME. IM notifies some event (input mode change, etc.) to IME by ImeNotifyEvent (IME_NE_KEYEVENT).
  
• IME requests IM to display some IM information (conversion string, input mode, candidate window, etc.) by ImRequestEvent. IME informs IM that some result string is generated by ImRequestEvent.
  
• IM informs the change of IM status to the application window procedure.
  
• An application may pass back the information to IM via WinDefWindowProc.
  
• IM requests Part Class to display the IM status information.
  
• IM requests PMWIN to change translation table. IM returns the result string to PMWIN.
  
• PMWIN pass KBD event and result string to an application.
  10.
  An application can control IM. An application can request string conversion By ImXxx.

  At the IM input model, all key event is processed in the application thread context. Application

  There are three levels in the IM support level of the application.

  • Level 1 Application
  The application does not know the IM. The application does not communicate with any IM module. When the application may use the system control window class (ex. single edit field), the user can perform on-the-spot-conversion on the window.

  • Level 2 Application
  The application provides the information of the conversion to the IM system. The applcation can specify the position and font information of the conversion window. The application can control the IM mode such as IM mode on/off.

  • Level 3 Application
  The application can control the IM system such as the level 2 applcation. Additionally the applcation gets the information of the conversion from the IM system. The application can display the conversion string in the application window by getting the conversion information from the IM system. The application can get the result string from the IM system by using IM API, not from PMWIN's WinGetMsg. The application can convert the string without the IME's displaying by ImConvertString API.
  
  PMWIN

  PMWIN gives the keyboard event to IM module. IM module gives back the translated characters to PMWIN when IME generates the translated characters from the keyboard event given by PMWIN. Finally PMWIN gives the keyboard event and the translated characters to the Application by returning of WinGetMsg.
  KBD DD

  KBD DD generates the keyboard event from the keyboard hardware interrupt. The keyboard event is queued into the PMWIN system queue.
  Part Class

  The IME vendor can provide the unique user interface. When the IME provides the name of IME window at ImeInitialize, the system (IM window) forwards the messages related to user interface to the IME window. The IME window can dispatch the messages to the IME unique Part Class window. The system provides the some default Part Classes. The IME can use the default Part Class if IME does not need the unique user interface. The detail is described in "Default IM Classes" section.
  IME

  The IME generates the translated characters from the keyboard events. When the IME needs to display the candidate string, the IME should request the system to generate the user interface messages for the IME window in order that the application can interc ept the user interface messages.

  The IME receives the key event conforming to PM SPEC. The key event has the IME virtual key as the additional information. The IME virtual keys are defined to all keys including the alphabet keys.
  IM

  The IM system is the extension module of PMWIN for the DBCS conversion support. The IM system gets the keyboard event from PMWIN. The IM system pass the keyboard event to the current IME. The IM system provides the helper IM API for the IME module.

   The IM syetm is described as following figure:

  The IM module can be decomposed into following:

  1.
  IM Interface (API)
  The IM interface has the external API. The IM interface dispatches the API to other components.

  • Message Manager
  The Message Manager translates the WM_IMECONTROL message to the IM APIs.

  • Instance Manager
  This manages IM instance and IM Part instance.

  • KBD Resource Manager
  The KBD Resource Manager manages the translation tables. The KBD Resource Manager handles the keyboard event and requests PMWIN to change the translation table.

  • IME Manager
  This is the interface component to IME. This component calls the APIs exported by the IME module. The IME Manager manages the list of the installed IMEs.

  • Display Service Manager
  The Display Server Manager manages the address of the display handler per IM instance.

  • IM Window
  The IM window is the interface window to the application. The application can send WM_IMECONTROL message to the IM window in order to control the IME. The IM window gets back the IM related messages from the application when the application calls ImIsIMEM essage or WinDefWindowProc.

  • Default IM Classes
  The IM system provides the following pre-defined IM window classes.

  • Default IME Window Class
    
  • WC_IME_CONVERSION
    
  • WC_IME_STATUS
    
  • WC_IME_CANDIDATE
    
  • WC_IME_INFOMSG
    
  • WC_IME_REGWORD
  The function detail of the default IM Classes is described in "32 bit Input Method Editor Interface" section.
  9.
  Installation/Registration
  ThismanagesIMEregistration .InorderthataIMEcanbeusedatOS / 2system ,theIMEmustbeinstalledintoOS / 2system .

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