public interface TreeModel

class StringArrayTreeModel implements TreeModel {
    String[][] arr = new String[][] {
            {"Colors", "Letters", "Numbers"},
            {"Red", "Green", "Blue"},
            {"A", "B", "C"},
            {"1", "2", "3"}
        };

    public Vector getChildren(Object parent) {
        if(parent == null) {
            Vector v = new Vector();
            for(int iter = 0 ; iter  iter + 1 && arr[iter + 1] != null) {
                    for(int i = 0 ; i

And heres a more "real world" example showing an XML hierarchy in a `Tree`:

```java
class XMLTreeModel implements TreeModel {
private Element root;
public XMLTreeModel(Element e) {
root = e;
}

public Vector getChildren(Object parent) {
if(parent == null) {
Vector c = new Vector();
c.addElement(root);
return c;
}
Vector result = new Vector();
Element e = (Element)parent;
for(int iter = 0 ; iter

Another real world example showing the `com.codename1.io.FileSystemStorage` as a tree:

```java
Form hi = new Form("FileSystemTree", new BorderLayout());
TreeModel tm = new TreeModel() {
@Override
    public Vector getChildren(Object parent) {
        String[] files;
        if(parent == null) {
            files = FileSystemStorage.getInstance().getRoots();
            return new Vector(Arrays.asList(files));
        } else {
            try {
                files = FileSystemStorage.getInstance().listFiles((String)parent);
            } catch(IOException err) {
                Log.e(err);
                files = new String[0];
            }
        }
        String p = (String)parent;
        Vector result = new Vector();
        for(String s : files) {
            result.add(p + s);
        }
        return result;
    }
@Override
    public boolean isLeaf(Object node) {
        return !FileSystemStorage.getInstance().isDirectory((String)node);
    }
};
Tree t = new Tree(tm) {
@Override
    protected String childToDisplayLabel(Object child) {
        String n = (String)child;
        int pos = n.lastIndexOf("/");
        if(pos
@author Shai Almog