☜	MWAPI - Pointer Events Draft MDC Standard					☞

9.1.2 Pointer Events

Pointer events (i.e. click, double click, pointer down, pointer up, pointer move, and pointer drag events) occur when the user takes certain actions with the pointer and the pointer is located within the viewport of a window created via the MWAPI. If the pointer is within a gadget for which a pointer event can occur, then the event occurs for that gadget. Otherwise, if the pointer is within a window for which a pointer event can occur, then the pointer event occurs for that window.

A pointer down event, indicated by an etype value equal to "PDOWN", occurs when the user presses a pointer button.

A pointer up event, indicated by an etype value equal to "PUP", occurs when the user releases a pointer button. A pointer up event occurs for the window or gadget in which the pointer was located when the preceding pointer down event occurred, even if the pointer was subsequently dragged outside of that window or gadget.

A pointer move event, indicated by an etype value equal to "PMOVE", occurs when the user moves the pointer with no pointer buttons pressed.

For a scroll gadget, a pointer drag event, indicated by an etype value equal to "PDRAG", occurs when the user drags the gadget’s position indicator. For windows and other gadget types, a pointer drag event occurs when the user moves the pointer with at least one pointer button pressed. Pointer drag events occur for the window or gadget in which the pointer was located when the drag was initiated, even if the pointer is subsequently dragged outside of the window or gadget in which the drag began.

A click event, indicated by an etype value equal to "CLICK", occurs when the user presses and releases a pointer button without an intervening change in the pointer position. For a button click action by the user, the following sequence of events occurs: pointer down, click, and pointer up.

A double click event, indicated by an etype value equal to "DBLCLICK", occurs when (a) the user twice presses and releases a pointer button without any intervening changes in the pointer position and (b) the second button press occurs within a specified time interval of the first button press. The time interval is not specified by the MWAPI and may be controllable by the user. For a button double click action by the user, the following sequence of events occurs: pointer down, click, pointer up, pointer down, double click, and pointer up.

A pointer event does not occur if the FILTERIN especattribute is present for the event and the pbuttoncode associated with the event is not one of the pbuttoncodes present in the value of that FILTERIN especattribute.

No behavior is defined for events related to pointer buttons which are not mapped to pointer button codes.

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Copyright © Examples: 1995-2024 Ed de Moel;
Copyright © Annotations: 2003-2008 Jacquard Systems Research
Copyright © Annotations: 2008-2024 Ed de Moel.

Some specifications are "approved for inclusion in a future standard". Note that the MUMPS Development Committee cannot guarantee that such future standards will indeed be published.

This page most recently updated on 14-Nov-2023, 22:11:29.

For comments, contact Ed de Moel (demoel@jacquardsystems.com)