Tobias Oetiker schrieb: > As explained the other day I am working on a canvas cell renderer, > it has been working pretty well for some time now, except that the > contents of the canvas cells misteriously dissapeared when > scrolling through the table. I have no investigated the problem and > found the reason (and a solution). > > The table.pane.Pane creates the content of the table pane by > joingin html fragments representing the individual rows of the > table and in the end inserting the result into the body of the > table. > > The problem with the canvas element is that it can only have > rendered content while it is a DOM node, this means that if the > table pane recreates the table content by concatinating cached HTML > fragments and then reinserting them into the DOM, the content of > the rendered canvas cells will be lost. > > short of rewriting the table widget I have found a workaround for > the problem. My cell renderer now contains a cache map storing the > canvas elements once they are rendered. Whenever the renderer is > triggered, it lookes up the elements in the cache and replaces the > freshly created canvas node with the already rendered aequivalent. > > is the table widget realy faster by doing string manipulation > instead of jugging dom nodes ? > Yes! Especially on older browsers the difference is huge. It is the difference between unusable and decent scrolling speed. We had implementations for both and even on newer browser the still is a difference.
Best Fabian -- Fabian Jakobs JavaScript Framework Developer 1&1 Internet AG - Web Technologies Ernst-Frey-Straße 9 · DE-76135 Karlsruhe Telefon: +49 721 91374-6784 [email protected] Amtsgericht Montabaur / HRB 6484 Vorstände: Henning Ahlert, Ralph Dommermuth, Matthias Ehrlich, Thomas Gottschlich, Robert Hoffmann, Markus Huhn, Hans-Henning Kettler, Dr. Oliver Mauss, Jan Oetjen Aufsichtsratsvorsitzender: Michael Scheeren ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ qooxdoo-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/qooxdoo-devel
