/** Draws the edge structure of the tree */
public void drawEdges(Graphics2D gg) {
gg.setPaint(Color.black);
Enumeration nodeList = argument.getBreadthFirstTraversal().elements();
// For each vertex...
while (nodeList.hasMoreElements()) {
// Get its edge list...
TreeVertex vertex = (TreeVertex) nodeList.nextElement();
Enumeration edges = vertex.getEdgeList().elements();
// For each edge in the list...
while (edges.hasMoreElements()) {
TreeEdge edge = (TreeEdge) edges.nextElement();
// If we have several vertices on layer 0, only draw
// edges for layers below that
if (!(argument.isMultiRoots() && vertex.getLayer() == 0)) {
// If the edge has been selected with the mouse,
// use a thick line
if (edge.isSelected()) {
gg.setStroke(selectStroke);
}
gg.draw(edge.getShape(this));
// If we used a thick line, reset the stroke to normal
// line for next edge.
if (edge.isSelected()) {
gg.setStroke(solidStroke);
}
TreeVertex edgeSource = edge.getDestVertex();
}
}
}
}
/*
* Creates a line of width EDGE_SELECT_WIDTH for each edge
* and tests if mouse click was in that Shape's boundary.
* Returns the edge if one was selected, null otherwise.
*/
public TreeEdge testEdgeShapes(MouseEvent event) {
if (argument == null || argument.getTree() == null) return null;
double x = event.getX();
double y = event.getY();
BasicStroke edgeWidth = new BasicStroke(EDGE_SELECT_WIDTH);
if (argument.getBreadthFirstTraversal() == null) return null;
Enumeration nodeList = argument.getBreadthFirstTraversal().elements();
while (nodeList.hasMoreElements()) {
TreeVertex vertex = (TreeVertex) nodeList.nextElement();
if (argument.isMultiRoots() && vertex.getLayer() == 0) continue;
Enumeration edges = vertex.getEdgeList().elements();
while (edges.hasMoreElements()) {
TreeEdge edge = (TreeEdge) edges.nextElement();
Shape shape = edge.getShape(this);
Shape wideEdge = edgeWidth.createStrokedShape(shape);
TreeVertex child = edge.getDestVertex();
if (wideEdge.contains(x, y)) {
edge.setSelected(!edge.isSelected());
return edge;
}
}
}
return null;
}