Simple Tree Model and Tree component from Codename One

TreeSample.java

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 < arr[0].length ; iter++) {
                v.addElement(arr[0][iter]);
            }
            return v;
        }
        Vector v = new Vector();
        for(int iter = 0 ; iter < arr[0].length ; iter++) {
            if(parent == arr[0][iter]) {
                if(arr.length > iter + 1 && arr[iter + 1] != null) {
                    for(int i = 0 ; i < arr[iter + 1].length ; i++) {
                        v.addElement(arr[iter + 1][i]);
                    }
                }
            }
        }
        return v;
    }

    public boolean isLeaf(Object node) {
        Vector v = getChildren(node);
        return v == null || v.size() == 0;
    }
}

Tree dt = new Tree(new StringArrayTreeModel());

Sample usage code for Tree & TreeModel.

From the Codename One project