[code] Menu Validation (MF_DISABLED bugged on PC?)

thomthom

This is what I always use for validation procs:


  def self.can_paste_proc
    if self.can_paste?
      MF_ENABLED
    else
      MF_DISABLED | MF_GRAYED
    end
  end

I though MF_DISABLED prevented the action from triggering. And that MF_GRAYED where used only for the visual effect.

thomthom

hmm... testing in SU8M1, you're right. MF_DISABLED seem to do nothing. Only MF_GRAYED seems to affect anything.
Though I imagine there is a reason I use MF_DISABLED | MF_GRAYED - just can't remember why. Can't find any notes on it.

thomthom

Same behaviour on SU6, 7.1 Windows.

Dan Rathbun

@thomthom said:

Though I imagine there is a reason I use MF_DISABLED | MF_GRAYED - just can't remember why. Can't find any notes on it.

I'll bet it's a cross-platform thangie... it does not seem to matter to Windows if the DISABLED bit is set, so no harm is done.

Need a Mac guy to test it and let us know.

Dan Rathbun

@thomthom said:

This is what I always use for validation procs:

Just being clear that the methods above are not the actual validation_proc. I try not to put conditional evaluations into the menu or toolbar procs, if I can do the decision in another place in the code. In most cases, the validation state does not change until the user actually clicks on the item (or button,) so it's better to change the menu item's (or button's) valid state within the command proc, or some other method that gets called. So when the change is made I just change the value of a @@validation class var (or @validation instance var,) and let Sketchup just pick up the value of that var when it must do a UI draw.

So creating a menu item, would look like:
item = menu.add_item('Some Menu Label') { ..execute_code.. } menu.set_validation_proc(item) { @@validation }

thomthom

Yea, that'd probably be better.

IN my case I'd need an observer, but it'd still be more efficient.

thomthom

Tested on OSX SU8.0M1 - Same behaviour, MF_DISABLED does nothing.

Dan Rathbun

@thomthom said:

hmm... testing in SU8M1, you're right. MF_DISABLED seem to do nothing. Only MF_GRAYED seems to affect anything.

@thomthom said:

Same behaviour on SU6, 7.1 Windows.

@thomthom said:

Tested on OSX SU8.0M1 - Same behaviour, MF_DISABLED does nothing.

Thanks go to ThomThom for filing a Google BugReport on this, 30 JAN 2011.

thomthom

I still wonder why I've been using MF_DISABLED...

Dan Rathbun

Covering your butt.. just in case the API changes in the future?

thomthom

Possibly. Maybe it was in another language where you had to gray and disable. ...Visual Basic...? Can't think of anything else where I've dealt with menus...