I note right at the end you say you're using 7u40. In the JavaFX 2.x series of releases it is true that TreeView misbehaved a bit around cell reuse. This should no longer be the case in JavaFX 8.0. In any case, the best option is to file a bug report and discuss it further in there, especially so if you can reproduce the issue in JavaFX 8.0.
One thing that sticks out: you don't say if you're using WeakEventHandler or EventHandler instances. If you're using EventHandler you could consider using WeakEventHandler. This may help to alleviate some of the memory leak. -- Jonathan On 9/10/2013 8:37 a.m., Scott Palmer wrote: > I'm investigating a memory leak and it seems that the culprit is event > listeners attached to TreeCells > > The GC roots of my leaks are deep in the JavaFX window/event system > > In a class extending TreeCell, am calling methods on such as: > > setOnContextMenuRequested(contextMenuRequestHandler); > setOnMouseClicked(mouseEventHandler); > setOnDragDetected(dragDetectedHandler); > > All of the event handlers in this case will have a reference to the > TreeCell, either via the implicit reference of the anonymous inner class, > or an explicit member > > I do this in updateItem when the cell is not empty and has a non-null item. > If updateItem is called and the cell is empty or has a null item then I > clear the event handlers with: > > setOnContextMenuRequested(null); > setOnMouseClicked(null); > setOnDragDetected(null); > > The problem is that TreeView doesn't seem to reuse TreeCells very much. It > mostly creates new ones. This means that many TreeCells are disconnected > from the scene graph and "lost" while there is still an event handler > connected to it. > > Am I doing something wrong? > This seemed like the correct way to deal with dragging and double clicking > on tree nodes. > > The tutorial here: > http://docs.oracle.com/javafx/2/ui_controls/tree-view.htm#BABDEADA > > only goes so far as to add a context menu. (My context menu needs to be > constructed dynamically.) So I'm not sure if I'm "allowed" to connect > event handlers to TreeCells in this way, but I don't know what the > alternative is. > > I suppose I would have to listen to something to ensure the TreeCell is > still part of the scene graph and disconnect the listeners when that > changes. It seems a bit awkward. > > > Scott > (I'm using 7u40)
