Description
This event is reported when the presses one finger on an object and then taps it with a second finger.
The event message reported as the result of ⎕DQ, or supplied as the right argument to your callback function, is a 5-element vector as follows :
| [1] | Object | ref or character vector |
| [2] | Event | 'GesturePressAndTap' or 497 |
| [3] | Flags | integer which reports the state of the gesture |
| [4] | Location | 2-element integer vector containing the y and x-position respectively of the point midway between the two fingers. These are reported in pixel coordinates relative to the origin (top-left corner) of the object reporting the event.. |
| [5] | Offset | 3-element integer vector whose first element is (currently) 0 and whose second and third elements contain the (y,x) offset of the second finger relative to the first. |
The Flags parameter [3] which reports the state of the Gesture, is an integer with the value 0, 1 (GF_BEGIN), or 4 (GF_END):
| Name | Value | Description |
| 0 | A gesture is in progress | |
| GF_BEGIN | 1 | A gesture is starting. |
| GF_END | 4 | A gesture has finished. |
When the user taps with his second finger, the object generates a GesturePressAndTap event with a Flags parameter of 1 (GF_BEGIN). Subsequently, until the user removes his first finger, it generates a series of GesturePressAndTap events with a Flags parameter of 0. When the user lifts his first finger away, the object generates a final GesturePressAndTap event, with a Flags parameter of 4 (GF_END)
No other event will be reported between the start and end of a series of GesturePressAndTap events.
The associated callback is run immediately while the windows notification is still on the stack. See High-Priority Callback Functions.
Returning zero from the callback disables any default handling by the operating system.