imaqGetLastEvent

NI Vision for LabWindows/CVI Function

imaqGetLastEvent

Usage

int imaqGetLastEvent(WindowEventType* type, int* windowNumber, Tool* tool, Rect* rect);

Purpose

Returns the last event that the user performed on an image window.

Note  Do not use this function if you have registered an event callback with imaqSetEventCallback().

Parameters

Name

Type

Description

type WindowEventType* On return, the last event that occurred, such as IMAQ_DOUBLE_CLICK_EVENT - The user has double clicked in a window. Set this parameter to NULL if you do not need this information.
windowNumber int* On return, the window number of the window in which the last event occurred. Set this parameter to NULL if you do not need this information.
tool Tool* If the event was IMAQ_DRAW_EVENT, tool is the ROI tool that the user drew with. Tool information is also returned for the IMAQ_CLICK_EVENT and IMAQ_DOUBLE_CLICK_EVENT. If the event was not IMAQ_DRAW_EVENT, IMAQ_CLICK_EVENT, or IMAQ_DOUBLE_CLICK_EVENT, the function ignores this parameter. Set this parameter to NULL if you do not need this information.
rect Rect* A rectangle describing the location of the event. Set this parameter to NULL if you do not need this information.

Return Value

Type

Description

int On success, this function returns a non-zero value. On failure, this function returns 0. To get extended error information, call imaqGetLastError().

Parameter Discussion

rect—For rect, the contents of the rectangle depend on the type, as follows:

  • IMAQ_CLICK_EVENT—The top left corner of the rectangle is the location of the click. The width and height of the rectangle are 0.
  • IMAQ_SCROLL_EVENT—The top left of the rectangle is the center of the displayed image. The width and height of the rectangle are 0.
  • IMAQ_DRAW_EVENT—The rectangle is the bounding rectangle of the drawn shape.
  • IMAQ_MOVE_EVENT or IMAQ_SIZE_EVENT—The rectangle is the new location of the window on the screen.

For all other events, the function ignores the rectangle.