FastTree already takes care of all of this, so I'd recommend using it. http://collectionofdemos.appspot.com/demo/com.google.gwt.demos.fasttree.FastTreeDemo/FastTreeDemo.html
On Wed, Mar 11, 2009 at 7:37 AM, gregor <[email protected]>wrote: > > I have never tried using StackPanel like that, but I did look at it's > code once to enhance it and I think it is at least as "complicated" as > Tree (in the sense it has many HTML "boxes") so I would guess it would > probably be if anything worse than Tree in your situation. > > The classic way to deal with large trees is to lazy load them by > layer, but obviously that is not an option for you as you only have > one layer. > > I think you'll have to figure out a creative way to design a widget to > deal with this edge case (1000 items). It's a bit difficult to suggest > anything because we don't know either the contents of the tree nodes > (what these 100 items are) or how they are used (presume user selects > them?) > > One idea that that immediately occurred to me was to use > DisclosurePanels. This has a right pointing triangle when closed, and > when clicked reveals the contents, rather like clicking the + on a > Tree. I am assuming also that the problem is purely rendering and that > there is no time problem fetching the 1000 items over RPC. You could > make a Composite widget like so: > > Choose a container, could be FlowPanel, VerticalPanel etc > Keep a list of the items as a member of this class, and a cursor to > keep an index against the list > Set a maximum number to be rendered at any one time, say a few more > than your happy days case of <=10 > Iterate through the list making DisclosurePanels and adding them to > the container as you go > If the list size > your chosen max, add a button bar to the bottom > giving forward/back options > > Etc, I'm sure you get the idea. I think rendering 10 - 15 > DiclosurePanels at a time will probably be quick enough. > > > > On Mar 11, 5:49 am, GWTFan <[email protected]> wrote: > > I read the threadhttp:// > groups.google.com/group/Google-Web-Toolkit/browse_thread/threa... > > on tree performance. > > > > We are having a similar issue with the tree, where most of the cases > > it would have 1-10 items. However rarely it would have 500-1000 items, > > which slows down IE badly. > > > > Ours is just one level hierarchy and I don't really need tree. Do you > > think using a stack panel would be faster than tree? > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/Google-Web-Toolkit?hl=en -~----------~----~----~----~------~----~------~--~---
