westor <[EMAIL PROTECTED]> writes: > One of the first things I cheked out with qooxdoo was a tree which opened > with data, delivered at runtime by backend script. I modified the > treefullcontrol example in the demo. > Really, it works fine, but for a bunch of entries its slow. > Now - with 0.6.6 - I noticed the treevirtual classes. Why are three kinds of > similar looking class structures available? Is treevirtual the class you > would suggest du do things? What are the advantages or disadvantages of > these classes?
The three tree implementations have been done at different times, each improving on the previous implementation. I implemented all but the original Tree class. TreeFullControl added a lot of capability to the original tree implementation and I originally had implemented those capabilities as an improvement on Tree (as part of the same class) but I was fairly unknown to the qooxdoo team at that time, and the speed of TreeFullControl vs Tree with only the Tree column (equivalent usage) was unknown, so it was requested that I make it an independent class. At this point, it would be reasonable to combine those two into a single class if/when someone gets a chance. It was long known that adding many items to a tree (with the traditional two implementations) was really, really slow. Rendering all of those objects is slow on Firefox, and incredibly slow on IE. The "right" way to implement a tree is to render only the portions of it that are actually visible at any one time (thus the term "virtual"). This is, of course, true with other more advanced gui elements such as a table, and Til's fabulously adaptable Table implementation laid the foundation for me to finally implement a virtual tree. TreeVirtual is brand new, and still under development. Although the interface may still change, it is beginning to stabilize. Usage, both in my own applications, in the Samba Web Administration Tool, and by a few other daring individuals who have chosen to use it in its early development state, is demonstrating that it is both useful and could still use some additional features and improvements. I continue to work on it. Depending on when 0.7 is released, it may or may not stabilize enough by that time to remove the EXPERIMENTAL tag from it. > Looks like treevirtaul is much faster, can I do anything with this class, > waht I was able to to with the other one? Yes, for anything larger than really small trees, TreeVirtual is *much* faster. You can do nearly everything with TreeVirtual that you can do with Tree and TreeFullControl. The big missing feature in TreeVirtual is drag 'n' drop, but when I requested suggestions for what people wanted with that, I got no replies, so I guess no one really cares. There are likely some other features of the other trees that don't exist in TreeVirtual that I'm not thinking of right now, but for most practical purposes, yes it supports generally what the others do. You're welcome to use TreeVirtual, but do be aware that the interface may still change in non-backward-compatible ways that will require at least minor changes to your code. Cheers, Derrell ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ qooxdoo-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/qooxdoo-devel
