org.netbeans.spi.viewmodel

Main features:

• One TreeView, or TreeTableView can be shared among different modules. Different modules can add different types of nodes to one view.
• Hierarchy produced by one module can be changed by another one.
  
• Allows to split UI and implementation to different modules.
• Performance and memory consumption of this model should be much better than Node based models.
• You do not need one instance of some class (Node) per one node visible in view. And you do not need one class per one node type.
  

How to use View Model API

Step 1.

public class TreeModelImpl implements TreeModel {

    public Object getRoot () {
        return ROOT;
    }
    
    public Object[] getChildren (Object parent, int from, int to) {
        if (parent == ROOT)
            return File.listRoots ();
        return ((File) parent).listFiles ();
    }
    
    public boolean isLeaf (Object node) {
        if (node == ROOT)
            return false;
        return ((File) node).isFile ();
    }
}

    JComponent treeView = Models.createView (
        Models.createCompoundModel (
	    Arrays.asList (new Model[] {
                new TreeModelImpl (),      // TreeModel
                new ArrayList ()           // list of ColumnModel s
            })
        )
    );

Step 2.

public class NodeModelImpl implements NodeModel {

    public String getDisplayName (Object node) {
        if (node == ROOT) return "Name";
        String name = ((File) node).getName ();
        if (name.length () < 1) return ((File) node).getAbsolutePath ();
        return name;
    }
    
    public String getIconBase (Object node) {
        if (node == ROOT) return "folder";
        if (((File) node).isDirectory ()) return "folder";
        return "file";
    }
    
    public String getShortDescription (Object node) {
        if (node == ROOT) return "Name";
        return ((File) node).getAbsolutePath ();
    }
}

Step 3.

public class NodeActionsProviderImpl implements NodeActionsProvider {

    public Action[] getActions (final Object node) {
        return new Action [] {
            new AbstractAction ("Open") {
                public void actionPerformed (ActionEvent e) {
                    performDefaultAction (node);
                }
            },
            new AbstractAction ("Delete") {
                public void actionPerformed (ActionEvent e) {
                    ((File) node).delete ();
                }
            }
        };
    }
    
    public void performDefaultAction (Object node) {
        try {
            JFrame f = new JFrame ("View");
            f.getContentPane ().add (new JEditorPane (((File) node).toURL ()));
            f.pack ();
            f.show ();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Step 4.

public class TableModelImpl implements TableModel {

    
    public Object getValueAt (Object node, String columnID) {
        try {
            if (node == ROOT) return null;
            if (columnID.equals ("sizeID")) {
                if (((File) node).isDirectory ()) return "<dir>";
                return "" + new FileInputStream ((File) node).getChannel ().size ();
            }
        } catch (Exception e) {
            e.printStackTrace ();
        }
        return "";
    }
    
    public boolean isReadOnly (Object node, String columnID) {
        return true;
    }
    
    public void setValueAt (Object node, String columnID, Object value) {
    }
}

    ArrayList columns = new ArrayList ();
    columns.add (new ColumnModel () {
        public String getID () { return "sizeID"; }
        public String getDisplayName () { return "size"; }
        public Class getType () { return String.class; }
    });
    JComponent treeTableView = Models.createView (
        Models.createCompoundModel (
            Arrays.asList (new Model[] {
                new TreeModelImpl (),           // TreeModel
                new NodeModelImpl (),           // NodeModel
                new TableModelImpl (),          // TableModel
                new NodeActionsProviderImpl (), // NodeActionsProvider
                columns                         // list of ColumnModel s
            })
        )
    );

How to use Filters

• TreeModelFilter: this filter can be used to hide fome files, to add some virtual filesystems, to add content of zip files to original tree, and so on.
• NodeModelFilter: can be used to change names, icons or tooltips for existing files.
• TableModelFilter: can be used to modify content of columns.
• NodeActionsProviderFilter: can be used to add a new actions to pup-up menus, of to redefine default action.