[KDev4] SimpleOutputView Renewal

[Matt Rogers]

On Saturday 12 May 2007 09:02, dukju ahn wrote:
> 2007/5/12, Matt Rogers <mattr at kde.org>:
> > On Saturday 12 May 2007 08:10, dukju ahn wrote:
> > > Now is the time to make SimpleOutputView into "Complex"OutputView.
> > >
> > > What I want to implement first is some kind of integration with
> > > MakeBuilder. In KDev3.4, when compile error occurs we could go to the
> > > error spot just by clicking the gcc error string in Message tab.
> > > I plan to port it or rewrite it to KDev4.
> > >
> > > Now questions are
> > >
> > > 2.
> > > Do we have any special reason why the current output widget
> > > uses QStdModelItem instead of KTextEdit?
> > > If we use QStdModelItem, the user can't copy the
> > > outputs of commands. Also, the appearence of output is ugly IMHO.
> > > More severe problem is that listview gets slower when there are huge
> > > numbers of output lines. Think about building entire KDE project or
> > > entire firefox.
> >
> > Yes, we want a model. Write a custom delegate or custom view if you don't
> > like the appearance of it. I don't think KTextEdit will serve our needs
> > here, since I'd like to share this particular model/view approach with
> > the new equivalent of the problems tab in kdev3.
>
> But then how can we cope with the slowing-down situation when  the
> outputs become very very long??
> I've seen in kdelibs.com that Qt4's QListView in its installer becomes
> slow when he displays very long file list. Apart from this, It is easily
> anticipated that QListView becomes slower with long list.
>

Provide some hard numbers. Do some profiling. See how long it really takes. I 
refuse to make a technical decision w/o anything to back up other than a 
website posting that says they see a slowdown. If we're only adding a few 
lines every half a second or so, does that slowdown matter? When does the 
slowdown occur? During scrolling? During rendering? Get some facts to back up 
your statement rather than relying on somebody else, especially when they 
probably haven't provided any numbers to back up their statements with 
either.

Find out how many lines would be in a QListView if we stuffed the output 
of "make VERBOSE=1" when compiling kdelibs into the list view. Assume that 
there's one item per line. Add the equivalent number of lines for one file 
every 500 or 250ms. Run some tests and get some numbers, and then come back 
and we'll make a decision based on those facts.
-- 
Matt