🚀 go-pugleaf

Thanks!  Helpful!  But I'm still kind of confused how GraphModel and TreeModel
hook up to a TreeControl. Could you post or email me an explanation or some
source code that covers how the one interacts with the other.

thank you very much.

Alex

Tad Frysinger wrote:

> In article <37837FF6.654DDC32@sema4.com>, ahumphreys@sema4.com says...
> > What is the best way to populate a java tree from a dataset (or just on
> > the fly)?  I don't know how many nodes we're going to have, so I can't
> > really set up the appropriate number of GraphLocations in the code -- it
> > needs to be done dynamically.  Thanks. -alex
> >
> >
> Loop through the dataset, grab the info you need and build the tree.
> Here is a fragment where I am adding database metadata (column
> information) to a tree that describes a database table.
>
> while (rsColumnList.next())
> {
>   // Now add a description for this particular column
>   columnDescNode = new DefaultMutableTreeNode(
>                     new Pair( imageCol,
>                               rsColumnList.getString( "COLUMN_NAME" )));
>   treeModel.insertNodeInto( columnDescNode,
>                             columnsNode,
>                             columnsNode.getChildCount() );
> }
>
> The DefaultMutableTree node takes an object that it stores in its
> 'userObject' instance variable.  This is usually a string, but in my
> example I am using a JGL Pair object.  This means I also need to have a
> renderer assigned to my tree that knows how to get into that Pair()
> object and update a renderer component appropriately:
>
> class PairTreeCellRenderer extends DefaultTreeCellRenderer
> {
>
>    public void PairTreeCellRenderer()
>    {
>
>       setLeafIcon( null );
>       setClosedIcon( null );
>       setOpenIcon( null );
>
>    }
>
>    public Component getTreeCellRendererComponent(JTree tree,
>                                                  Object value,
>                                                  boolean sel,
>                                                  boolean expanded,
>                                                  boolean leaf, int row,
>                                                  boolean hasFocus)
>    {
>       super.getTreeCellRendererComponent( tree,
>                                           value,
>                                           sel,
>                                           expanded,
>                                           leaf,
>                                           row,
>                                           hasFocus );
>       pair = (Pair) ((DefaultMutableTreeNode)value).getUserObject();
>       setText( pair.second.toString() );
>       setIcon( (Icon)pair.first );
>       selected = sel;
>       return this;
>    }
>
>    public String getToolTipText()
>
>    {
>
>       return "";
>
>    }
>    private Pair pair;
> }
>
> Tad Frysinger (TeamB)