Color picker problem

[jhonny03]

i have problem on color picker which is
when cancel was press the chosen color was white..it is maybe
that is the default color..

what i want is that when cancel was pressed then no changes on the
current color chosen.

 

[Tore Bleken]

Escape means -1. In other words, you may need to check the return value, and provide a default if it's -1.

 

[Mike Lewis]

The default colour is black, which is zero.

If you choose white, the value is 16777215.

If you press Cancel or hit ESC, the value is -1.

The confusion arises because GETCOLOR() returns a 24-bit value, and (2^24) = 1 = 16777215. On that basis, -1 is the same as white. So, you can explicitly set, say, _SCREEN.Backcolor to -1, and it will appear as white. But this isn't really a problem, as you will always explicitly test for -1 to see if GETCOLOR() was cancelled.

Mike

__________________________________
Mike Lewis (Edinburgh, Scotland)

Visual FoxPro articles, tips and downloads

 

[jhonny03]

thanks for the reply guys..
is it possible to code it?

getcolo()
if cancel was pressed then

​

gray color
endif

 

[Mike Lewis]

Yes, this is easy.

lnColor = GETCOLOR()
IF lnColor = -1
  lcColor = 8421504   && dark grey
ENDIF

If you want a lighter shade of grey, use, say, 12632256.

Mike

__________________________________
Mike Lewis (Edinburgh, Scotland)

Visual FoxPro articles, tips and downloads

 

[jhonny03]

tnx mike..
another thing..
is there a possible way to dissable white color to be chosen
by the user?

 

[Tore Bleken]

If they select white, then present a messagebox telling it's an illegal color, and present the color picker once more.

 

[jhonny03]

ok thanks guys..

 

[Mike Lewis]

If you want to want to prevent them selecting white in the first place (rather than displaying a message to say it's an illegal value), you could create your own custom colour picker. Make it an ordinary VFP modal form, with a shape for each permitted colour, and a pair of buttons for OK and Cancel. When the user clicks on one of the shapes, save the corresponding numeric code in a form property, and then return that value when the form is closed.

You might well decide that's too much trouble, and also that it would have the disadvantage of a non-standard appearance. But it might be better than the alternative, that is, permitting the user to make a choice and then turning round and saying that the choice is illegal - which is a UI no-no, in my humble o.

Mike

__________________________________
Mike Lewis (Edinburgh, Scotland)

Visual FoxPro articles, tips and downloads

 

[Tore Bleken]

Check these articles for an alternative color picker.

http://yousfi.over-blog.com/2015/01/create-a-simple-color-picker.html

http://yousfi.over-blog.com/2015/05/a-new-colorpicker-web-and-vfp-solution.html