[news.eclipse.tools] Re: pb building TreeView

[anthony.saucet@xxxxxxxxxxx (anthony saucet)]

In fact I think I have something working wrong. I don't know if it's my pc
or eclipse (or the 'Run' mode), but sometimes its behaviour is very
strange.
Now, everything is almost ok, but without modifying anything, the layout
has changed !
thx anyway for your help
anthony



anthony saucet wrote:

> When I was building the tree in memory, everything was ok, I followed your
> advices.
> But now I build it in a class and I have a stange pb.
> I build my DOM tree in memory with the root element from my DTD. I
> retrieve it (No problem.) and try to display it in the the treeView (pb).
> I got an inputChanged where new_input is null. And I don't know why!
> 'cause  I only have the rootElement in the document.
> Messages I got:

>     ContentProvider-inputChanged        // launching of the view
>     ContentProvider-inputChanged old=null
>     tree view            // setContentProvider
>     tree view            // setLabelProvider
>     TREEbuilder-getDoc[MASTER103: null]    //gets the rootElement
>     TREEbuilder-getDoc[MASTER103: null]
>     ContentProvider-inputChanged
>     ContentProvider-inputChanged old=null
>     ContentProvider-inputChanged new=null

> Do you have any idea ?
> thanks, anthony


> anthony saucet wrote:

> > I've resolved the pb. Instead of getting the root element (ElementImpl) of
> > my DOM tree, I retrieve the whole document (DocumentImpl), which will be
> > the root. Then my root element is a child of the doc.


> > anthony saucet wrote:

> > > You were right, now I size the array with getLength() and tree.setInput()
> > > works perfectly. It seems to build a tree in memory and then expand the
> > > tree in the view, BUT without the root element.
> > > What's the trick to display it?

> > > anthony



> > > Knut Radloff wrote:

> > > > I just noticed that you initialize your children array (elnts) to a
fixed
> > > size. The array you return must only have enough slots for
> > > > all the children and no extra null slots. That's probably what's
causing
> > the
> > > exception.
> > > > You need to size it to getChildNodes().getLength(). If you have no
> children
> > > an empty array will be returned.

> > > > Knut
> > > > "anthony saucet" <anthony.saucet@xxxxxxxxxxx> wrote in message
> > > news:b8bjer$6na$1@xxxxxxxxxxxxxxxx
> > > > > getChildNodes() is not null BUT getChildNodes().getLength() = 0 !!!
> > > > > I've printed out what happens in class contentProvider:
> > > > >
> > > > > getChildNodes: !null
> > > > > j: 0                             /* getChildNodes().getLength() */
> > > > > contentPovider getChildren end   /* end of method getChildren() */
> > > > > hasChild                         /* call method hasChild */
> > > > > contentPovider getChildren       /* calls method getChildren() */
> > > > >
> > > > > and when tries j = getChildNodes().getLength(), stops here and after
> lot
> > > > > of things I didn't catch, exception.
> > > > > anthony
> > > > >
> > > > >
> > > > > Knut Radloff wrote:
> > > > >
> > > > > > Does getChildNodes return null when there are no more children? You
> can
> > > set
> > > > > an exception breakpoint in the debugger and find
> > > > > > out.where the exception is occurring.
> > > > >
> > > > > > Knut
> > > > >
> > > > > > PS: Please continue the thread on eclipse.platform, eclipse.tools
> > should
> > > no
> > > > > longer be used and will be made read-only soon.
> > > > >
> > > > > > "anthony saucet" <anthony.saucet@xxxxxxxxxxx> wrote in message
> > > > > news:b8bbcv$u1r$1@xxxxxxxxxxxxxxxx
> > > > > > > I'm trying to build a TreeView in my perspective to have a look
on
> a
> > > DOM
> > > > > > > tree built in memory.
> > > > > > > I've implemented the TreeView with new TreeViewer, called
> > > > > > > setContentProvider() and setLabelProvider(). setInput() gets the
> > > > > > > rootElement of my DOM tree. Then in class contentProvider, the
tree
> > is
> > > > > > > being built by getChildren(), and everything seems ok.
> > > > > > > here's the code to get the children:
> > > > > > >
> > > > > > >    public Object[] getChildren(Object element) {
> > > > > > > Object elnts[]=new Object[20];
> > > > > > > int i = 0;
> > > > > > > int j=((Element)element).getChildNodes().getLength();
> > > > > > >
> > > > > > > for(Node child = ((Element)element).getFirstChild(); i<j;
> > > > > > > ((Element)element).getNextSibling()){
> > > > > > > elnts[i]=((Element)element).getChildNodes().item(i);
> > > > > > > i++;
> > > > > > > }
> > > > > > > return elnts;
> > > > > > >    }
> > > > > > >
> > > > > > > I don't really know what happens BUT when it arrives at the end,
> when
> > > no
> > > > > > > more child or items, it tries to continue and to create the tree
> and
> > > the
> > > > > > > following message appears:
> > > > > > > "Unable to create part: Tree" from
> > > > > > > eclipse.core.internal.runtime.InternalPlatform
> > > > > > > and the exception: "nullPointerException".
> > > > > > >
> > > > > > > Does anybody have an idea of what I need to do, or what I missed
?
> > > > > > > many thx
> > > > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >