What about making your treeitem-widget an absolutPanel for example,
put both - your lable and button in it along with a small switch-
function to make only one of the visible at a time. This may cause
some perfomance problems but when it's not that much of three items we
are speaking about, you man not even notice it.

On 24 Apr., 08:48, Ben FS <ben.su...@gmail.com> wrote:
> > 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.
>
> I am now restricting myself to only store textual / markup in each
> tree node, which makes this workaround possible and gets my code back
> to a working state with GWT 1.6. It's not ideal, and there are some
> styling issues, but I'll make do with this for now.
>
> > > 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'm still interested in how to do this, when you have time to give me
> some pointers.
>
> Do you know whether the "FastTree", as referenced in the issue
> comments, would work better for what I'm trying to do?
>
> Thank you,
> Ben.
>
> > 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 -- Hide quoted text -
>
> > - Show quoted text -
>
>
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups 
"Google Web Toolkit" group.
To post to this group, send email to Google-Web-Toolkit@googlegroups.com
To unsubscribe from this group, send email to 
google-web-toolkit+unsubscr...@googlegroups.com
For more options, visit this group at 
http://groups.google.com/group/Google-Web-Toolkit?hl=en
-~----------~----~----~----~------~----~------~--~---

Reply via email to