> Ah, I see what you mean. Sorry for not reading the issue report more > carefully the first time around. No problem, thanks for increasing the priority and for testing the issue across browsers.
> For the moment, simply cloning the original widget and using that clone > seems to be the best workaround. I've tried this, but can't get it to work right. First, I don't know how to make this work in general, because Widget doesn't have a clone () method. Second, for the various subclasses of Widget that I've tried, so far all of them lose their "content" when they are removed from the tree - so I can't just keep a reference. The only general approach I can think of is to wrap every node in a panel from the start, so that I can add/remove from that panel as needed. I'm pretty sure I tried something along these lines a year ago and found it to be problematic (too "heavy", as I recall). In my existing code, most of my TreeItem content is HTML, so it should be possible for me to "clone/copy" just the content as a String, squirrel it away and, after editing, return the node to its normal state by inserting a newly instantiated HTML object. I'll try this and see if I can get it to work - but it precludes me from using anything other than text or HTML in each node. > You could also try appending the button the > way you've been doing before, but it'll take some tinkering around to get it > hooked up properly and have the click event reach the handler. I've done a lot of tinkering already, without success. My tree has a SelectionHandler, and that seems to keep the ClickHandler from executing when the Button's Element is appended to the DOM directly. I read the memory leak / cycle / event listener article, and I tried adding a call to sinkEvent(Event.ONCLICK), but it didn't work. I'm basically poking around in the dark ... if you can think of a workaround, I'd like to try it. I think the relevant conditions are: a Tree with SelectionHandler, OpenHandler, CloseHandler and onSelection () should dynamically append a Button with a ClickHandler next to the TreeItem content (similarly, onSelection() should first remove this Button from any previously selected nodes). > If keeping > clones around proves to be a problem (for example, having to do this for > more than a couple of widgets), let me know and we can dig in deeper on the > manual DOM.appendChild() workaround until Issue #2297 gets a fix. > > Hope that helps, > -Sumit Chandel Thanks, you've definitely been a great help. > > On Thu, Apr 23, 2009 at 1:12 PM, Ben FS <ben.su...@gmail.com> wrote: > > > Hi Sumit, > > > > Is there any reason why you couldn't just call treeItem.setWidget(b) ? > > Yes. See issue #2297 that I submitted one year ago. > > "TreeItem.setWidget deletes state/content of the widget that is > > replaced " > >http://code.google.com/p/google-web-toolkit/issues/detail?id=2297 > > > In short, when you call TreeItem.setWidget, it deletes the content/ > > state in the DOM of the existing widget. For widgets that only store > > their state in the DOM (such as the Label), this is bad > > news. > > > By default, when you supply text data to the Tree, it renders this > > text in each TreeItem as a Label. I want to dynamically modify an > > individual node (make it editable), and after editing or when a > > different node is selected, return the node to the original state. > > Let's say I do this: > > > Widget normal = treeItem.getWidget(); // save this for later > > treeItem.setWidget(someEditor); > > // do some editing, then later in another event handler > > treeItem.setWidget(normal); > > > The debugger will show that, as soon as setWidget executes, the text > > of the original Widget, in variable "normal", has been erased. Refer > > to the issue I linked above to see the TreeItem source code that > > causes this effect. Again, it only matters for Widgets that store > > their state in the DOM (I don't know which these are, but I know it > > includes Label). > > > > That should change the tree item to the button widget and also properly > > register > > > the click handlers on the button so that the handler is fired all the way > > > out. > > Yes, and this does work. But I want to be able to make the change only > > temporary, and return the node to its original state after some time. > > I want it to be reversible. I tried various approaches in the past, > > and finally got one to work (i.e. appending a Button next to the > > existing Widget, but since TreeItem does not have an "append" method, > > I directly manipulate the DOM to achieve this effect in a reversable > > manner). This approach no longer works in GWT 1.6 - the Button event > > handlers no longer run. > > > Can you suggest a better approach, please? I feel there is probably a > > way to achieve this (reversably show an editor control, return to > > normal node state afterwards) that is better than what I've tried, but > > I have not been able to figure it out on my own ... perhaps a way to > > save the previous Widget without having its state modified by the > > TreeItem.setWidget call? Is it as simple as cloning/copying that > > original Widget? > > > > Hope that helps, > > > -Sumit Chandel > > Thank you for taking the time to respond, it is much appreciated. > > > > On Tue, Apr 21, 2009 at 9:50 AM, Ben FS <ben.su...@gmail.com> wrote: > > > > > I'd like to dynamically insert a Widget into/next to a single > > > > TreeItem, whenever a TreeItem is selected, but event handlers on the > > > > Widget never fire when I do this. > > > > > My approach so far: I dynamically manipulate the DOM of a single > > > > TreeItem, when a selection event occurs. First I insert a DIV sibling, > > > > and then I insert the Widget into that placeholder. Something like > > > > this: > > > > > Button b = new Button("Click me", new ClickHandler() { > > > > public void onClick(ClickEvent event) { Window.alert("I was > > > > clicked!"); } > > > > }); > > > > > Element itemDiv = treeItem.getElement(); // the TreeItem's underlying > > > > element > > > > Element spanEdit = DOM.createSpan(); // a container, perhaps this > > > > is not necessary > > > > DOM.appendChild(itemDiv, spanEdit); > > > > > DOM.appendChild(spanEdit, b.getElement()); > > > > > The button appears in the TreeItem when the TreeItem is selected, but > > > > I am not able to generate any click events when I try to click on the > > > > button with the mouse. I've also tried replacing the Button with > > > > direct HTML, as follows: > > > > > HTML h = new HTML("<a href='javascript:alert();'>Click me for alert</ > > > > a>"); > > > > > Once inserted into the TreeItem, on mouseover the browser status bar > > > > shows the link target, but clicking on it does not generate a popup. > > > > > My sense is that I need to do something else when I insert an Element > > > > into the DOM, to ensure that it participates in the event handling > > > > correctly. Yes? What else do I need to do? > > > > > Perhaps the Tree's SelectionHandler is interfering - a mousedown on > > > > anything within a tree's node triggers a selection event and no other > > > > events are processed? > > > > > Note: This used to work for me, using GWT 1.4.62, but even then only > > > > when the inserted Widget was a Button (for all other Widget's that I > > > > tried, the click event never reached the declared handler). > > > > > Note: I would prefer to do all this without manipulating the DOM, but > > > > there is a bug in TreeItem, since early version of GWT, that prohibits > > > > me from dynamically removing and later replacing the TreeItem's > > > > content. > > > >http://code.google.com/p/google-web-toolkit/issues/detail?id=2297 > > > > > Thanks for any help you can provide!- Hide quoted text - > > > > - Show quoted text -- Hide quoted text - > > - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group. 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