Re: [gnustep/libs-gui] NSPopUpButton's popup menu in pulldown mode displaying fix (#43)

[Wolfgang Lux]

> Am 20.12.2019 um 16:11 schrieb Fred Kiefer <address@hidden>:
> 
> ...
> 
> There you just describe that now the popup looks the same whether in pull 
> down or in popup state. But what is the reason for this change? As I wrote I 
> am happy with getting rid of all this special code, but last time I tried to 
> do this it was rejected.

I don't recall whether I was involved in that rejection or not, but if I wasn't 
I'd think that it was the correct move.

Regarding the different behavior with regard to the title cell, it apparently 
dates back to the heyday of OpenStep (and presumably the original NeXTstep as 
well). The idea seems to be that the title that is visible in the pop up button 
cell when the menu is not visible should be backed up by an element of the 
associated menu. In pop up mode this would be the selected item, while in pull 
down mode it is invariably the first element of the menu (since the title of 
the pull down is not supposed to change depending on the user's last 
selection). I think that's nothing that GNUstep can or should change.

That only leaves you with the option whether to display the title item when the 
pull down is visible or to not display it. If you wanted to display the title, 
the only reasonable choice for that would be such that the title item appears 
above the button itself (because otherwise you would redundantly display the 
same information twice). But then that doesn't work that well if you display an 
icon in the button cell rather than text (useful, for instance, when you want 
to make NSToolbar buttons with an attached pull down menu) and the popup 
button's width and/or height do not match the width or height of the menu 
(items). Also beware that the menu does not necessarily need to appear at the 
bottom of the pop up button. You can set the preferredEdge property of the 
button cell to make it appear on one of the sides of the button (or even appear 
attached to the top edge, although I don't see a reason for doing that). But of 
course these are all aesthetic judgements so feel free to disagree.

Wolfgang