DoubleClick returns an integer value of 0 or 1 to the variable passed to it.
If a mouse click occurs immediately after DoubleClick is called, the variable passed to DoubleClick will return a 1 given the following conditions. 1) The time elapsed between the call to DoubleClick and a mouse-click is less than 15 ticks (a tick is equal to one sixtieth of a second). 2) The vertical location of the mouse dose not move more that 1 pixel. If those two conditions are not met then the variable will equal 0.
If that description sounds more like a single-click function it's because that is what it really is, but who would want an external called SingleClick?
If you have ever tried checking for a double-click on a 4D scrollable area then you know why I call this external DoubleClick.
SYNTAX:
DoubleClick(numvar)
numvar : integer variable
This is the integer used to test for the mouse click.
EXAMPLE: A 4D scrollable Area Script
DoubleClick(vDblClick)
If(vDblClick=1)
`A double-click occurred on a list element
`so process the code for that action.
End if
Installation:
You can install DoubleClick directly into your application database or 4D application by using the 4D External Mover. If you only want it installed in a specific database application, choose the respective database name resource file and install it there. Hold down the option key before opening the resource file, otherwise, it will not show up in the choose-file dialog box.
Note: Please read the 4D Manual about how to install an external procedure if you have not done this before.
b) You may post this external on any private or public Commercial OR non-commercial bulletin board or service, provided, this Technical Note accompanies the software, and Howard E. Sander III is identified as the author of the work.
c) You may not remove or modify any of the identifying copyright notices, labels or marks.
d) You may not resell, this external to the general public without prior written permission from the author.
Warranty:
All externals are provided "as is" without warranty of any kind, either express or implied, including, but not limited to, the implied warranties of merchantability or fitness for a particular purpose.
