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

[anthony.saucet@xxxxxxxxxxx (anthony saucet)]

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
> > > > > >
> > > >
> > > >
> > > >
> > > >
> > > >