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API Reference

AEECLSID_TouchObserver

Brew Release
Brew MP 1.0.2
Description
This class implements IObserver. It watches events like EVT_POINTER_DOWN, EVT_POINTER_MOVE and EVT_POINTER_UP, to analyze pointer movements. It stores information like the pointer position where the linear move has started, the pointer position where the linear move ended, the distance traveled by pointer, its velocity, and the angle of the linear move. Touch Controllers query this interface to get information about the pointer movement and, based on this information, determine whether a certain gesture (for example: FLICK) has occurred.
Supported Events: The touch observer processes the events which it is observing (EVT_POINTER_DOWN, EVT_POINTER_MOVE and EVT_POINTER_UP), but it does not handle them. It just records the information about the pointer moves based on these events.
Touch observer handles the following events in the described manner:
Event                 Description
-----                 ------------------------------------------------------------


EVT_OBS_SETPROPERTY:  The touch observer responds to this event by attempting to set the
                      property identified by the 'wParam' parameter. Touch Observer only 
                      handles PROP_EX.

EVT_OBS_GETPROPERTY:  The touch observer responds to this event by attempting to retrieve the
                      property identified by the 'wParam' parameter. It only handles PROP_EX.




Properties:
Property           Description
--------           ------------------------------------------------------------

PROP_EX:                This property sets or retrieves an extended property value using a
                        TouchObserverPropEx structure. The extended property value is specified in
                        the structure's property ID field.

                        This structure also contains a size field and buffer pointer field.
                        For a get operation, on input, the size field contains the buffer size
                        in bytes and, on output, it contains the buffer's data size. For a set
                        operation, on input, the size field contains the buffer's data size.

                        Possible values for the property ID field include:

                           PROPEX_POINTER_LLM_ANGLE                
                           PROPEX_POINTER_LLM_DIST                 
                           PROPEX_POINTER_LLM_TIME                 
                           PROPEX_POINTER_LLM_VEL                  
                           PROPEX_LAST_EVT_POINTER_DOWN            
                           PROPEX_LAST_EVT_POINTER_UP              
                           PROPEX_POINTER_GET_OBSERVATION          
                           PROPEX_POINTER_START_OBSERVATION
                           PROPEX_POINTER_STOP_OBSERVATION
                           PROPEX_EVT_POINTER_OBSERVATION_TIMER   
                           PROPEX_TAP                              
                           PROPEX_DOUBLE_TAP                       


PROPEX_POINTER_LLM_ANGLE:
                        This extended property is used to retrieve the angle
                        (in degrees) of pointer linear movement.

PROPEX_POINTER_LLM_DIST:This extended property is used to retrieve the 
                        distance traveled by pointer linear movement.

PROPEX_POINTER_LLM_TIME:This extended property is used to retrieve the time.

PROPEX_POINTER_LLM_VEL: This extended property is used to retrieve the velocity.

PROPEX_LAST_EVT_POINTER_DOWN:
                        This extended property is used to retrieve the last 
                        pointer down event.

PROPEX_LAST_EVT_POINTER_UP:   
                        This extended property is used to retrieve the last 
                        pointer up event.

PROPEX_POINTER_GET_OBSERVATION:  
                        This extended property is used to retrieve the current
                        observation (Tap, Double Tap or Last Linear Movement (LLM))
                        being analyzed by the touch observer.



PROPEX_POINTER_START_OBSERVATION:
                        This extended property is used to set a new observation for the
                        touch observer. The touch observer will start analyzing 
                        pointer events for a particular observation (Tap, Double Tap or 
                        Last Linear Movement (LLM))
                                 

PROPEX_POINTER_STOP_OBSERVATION: 
                        This extended property is used to stop observation for the
                        touch observer. The touch observer will stop analyzing
                        pointer events for a particular observation (Tap, Double Tap or
                        Last Linear Movement (LLM))


PROPEX_EVT_POINTER_OBSERVATION_TIMER:
                        This extended property is used to set or retrieve the time
                        period which is used by the observer to analyze events
                        for a linear move. The touch observer only analyzes events
                        which are generated in this time period before it received
                        EVT_POINTER_UP.
Instantiaion
None
Cleanup
None
Default Interface Name
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