[haiku-bugs] Re: [Haiku] #6882: BTextControl layout issues
- From: "bonefish" <trac@xxxxxxxxxxxx>
- Date: Tue, 23 Nov 2010 19:05:44 -0000
#6882: BTextControl layout issues
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Reporter: axeld | Owner: yourpalal
Type: bug | Status: assigned
Priority: normal | Milestone: R1/beta1
Component: Kits/Interface Kit | Version: R1/Development
Resolution: | Keywords:
Blocked By: | Has a Patch: 0
Platform: All | Blocking:
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Comment (by bonefish):
Replying to [comment:3 axeld]:
> Replying to [comment:2 bonefish]:
> > Did you try to call `InvalidateLayout()` on the view? The
`BAbstractLayoutItem::SetExplicit*()` calls don't do that. Don't know if
for a reason.
>
> I did not try that, actually. However, since the views weren't even
added to a layout, I'm not sure if that would have had any effect.
If I understand you correctly (you added the views to a layout only after
setting the explicit size), then, yes it wouldn't have any effect.
> Shouldn't you know at least if there is a reason that they don't call
it, though? :-)
I haven't touched that code for more than four years. What do you expect?
:-)
> > > * the layout item contains 5 pixels spacing for the label - this
should be done via layout spacing, not being hard-coded.
> > That would be nicer indeed. The current implementation just maps to
the facilities of the non-layout version and there is no settable spacing.
If we want to change that, we should do so before R1, since it breaks
layouts relying on how it works now.
>
> I guess this would only come into play when there is no parent layout
involved?
If we want to add a public SetSpacing(), it shouldn't have any effect when
using the layout items. Though, I wasn't even considering to add such a
method yet. I was only thinking of adding a respective attribute.
> This would also finally deprecate the {{{SetDivider()}}} stuff (which
should then have no effect anymore).
This isn't related. When using the layout items, both the explicitly set
spacing and divider are ignored, otherwise both are used.
I may sound like a broken record, but BTextControl and BMenuField are also
on the list of interface kit class that need to be rewritten from the
scratch. The layout items solution is just a work-around for the
label/divider mess. The R2 interface kit should have a separate BLabel
class.
> > > * preferred size is broken (100 pixel width, how so?)
> > This is actually a tricky one. The obvious approach would be to
compute the preferred width based on the text width. The problem is that
it changes while typing, so the whole layout would need to be invalidated
all the time. My only idea for compensating for that would be a more
elaborate layout invalidation mechanism (track the different properties
(min/max/preferred size, alignment) individually (e.g. in a flags array
per layout/view)).
>
> Ah, indeed. One solution (that would follow what Java does, for example)
would be not to invalidate the layout on {{{SetText()}}} - this way, the
size would only actually matter when the layout is manually invalidated. I
am not saying I like this solution, though :-)
Nah, that's ugly. Either the text directly influences the preferred width
-- then text changes must invalidate the layout -- or it doesn't.
Otherwise one gets unpredictable effects for layouts that use the
preferred sizes of their items (we don't have any ATM, but a "flow" layout
would do exactly that). IMO an acceptable solution would be to compute the
preferred size only from the initial text and keep it after that. Maybe
invalidate and recompute it on certain events (e.g. font changes or when
the view is attached to a window).
--
Ticket URL: <http://dev.haiku-os.org/ticket/6882#comment:4>
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