[KDev4] SimpleOutputView Renewal

[Andreas Pakulat]

On 12.05.07 09:17:18, Matt Rogers wrote:
> 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.

We can easily use QTreeView, which is much more optimized than QListView
and its performance is much better than QListView, according to various
mails on qt-interest.

Also I doubt KTextEditor will work for this at all, because you may have
multiple instances of the outputwidget and no realy way to access them
from the plugin.

> 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.

Also adding currently inserts one line after another, which can be
optimitzed using a custom model instead of the standard-item-model.

Last but not least I think we should have a way to limit the number of
lines there so "huge" amounts of output won't be that bad in real life.

Andreas

@Mattr: QMake Manager can build programs since some time in Feb or
March...

-- 
You have an unusual understanding of the problems of human relationships.