ui-hw-task

ui-hw-task.java

package ua.edu.lnu.pif.ucs;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.InputEvent;
import java.awt.geom.Point2D;
import java.util.ArrayList;
import java.util.Random;

import edu.umd.cs.piccolo.PCanvas;
import edu.umd.cs.piccolo.PLayer;
import edu.umd.cs.piccolo.PNode;
import edu.umd.cs.piccolo.event.PDragEventHandler;
import edu.umd.cs.piccolo.event.PInputEvent;
import edu.umd.cs.piccolo.event.PInputEventFilter;
import edu.umd.cs.piccolo.nodes.PPath;
import edu.umd.cs.piccolo.nodes.PText;

public class GraphEditor extends PCanvas {
	
	PNode start = null;
	PNode finish = null;
	
	public GraphEditor(int width, int height) {
		setPreferredSize(new Dimension(width, height));
		int numNodes = 10;
		int numEdges = 10;

		// Initialize, and create a layer for the edges
		// (always underneath the nodes)
		PLayer nodeLayer = getLayer();
		PLayer edgeLayer = new PLayer();
		getRoot().addChild(edgeLayer);
		getCamera().addLayer(0, edgeLayer);
		PLayer nameLayer = new PLayer();
		getRoot().addChild(nameLayer);
		getCamera().addLayer(0, nameLayer);
		
		Random random = new Random();

		// Create some random nodes
		// Each node's attribute set has an
		// ArrayList to store associated edges
		for (int i = 0; i < numNodes; i++) {
			float x = random.nextInt(width);
			float y = random.nextInt(height);
			PPath node = PPath.createEllipse(x, y, 20, 20);
			node.addAttribute("edges", new ArrayList());
			nodeLayer.addChild(node);
			
			PText name = new PText(i+1+"");
			nameLayer.addChild(name);
			
			node.addAttribute("name", name);
		}

		// Create some random edges
		// Each edge's attribute set has an
		// ArrayList to store associated nodes
		for (int i = 0; i < numEdges; i++) {
			int n1 = random.nextInt(numNodes);
			int n2 = random.nextInt(numNodes);

			// Make sure we have two distinct nodes.
			while (n1 == n2) {
				n2 = random.nextInt(numNodes);
			}

			PNode node1 = nodeLayer.getChild(n1);
			PNode node2 = nodeLayer.getChild(n2);
			PPath edge = new PPath();
			((ArrayList) node1.getAttribute("edges")).add(edge);
			((ArrayList) node2.getAttribute("edges")).add(edge);
			edge.addAttribute("nodes", new ArrayList());
			((ArrayList) edge.getAttribute("nodes")).add(node1);
			((ArrayList) edge.getAttribute("nodes")).add(node2);
			edgeLayer.addChild(edge);
			updateEdge(edge);
		}
		
		// Create event handler to move nodes and update edges
		nodeLayer.addInputEventListener(new PDragEventHandler() {
			{
				PInputEventFilter filter = new PInputEventFilter();
				filter.setOrMask(InputEvent.BUTTON1_MASK
						| InputEvent.BUTTON3_MASK);
				setEventFilter(filter);
			}

			public void mouseEntered(PInputEvent e) {
				super.mouseEntered(e);
//				if (e.getButton() == MouseEvent.NOBUTTON) {
//					e.getPickedNode().setPaint(Color.RED);
//				}
			}

			public void mouseExited(PInputEvent e) {
				super.mouseExited(e);
//				if (e.getButton() == MouseEvent.NOBUTTON &&
//						(e.getPickedNode() != start || 
//						e.getPickedNode() != finish)) {
//					e.getPickedNode().setPaint(Color.WHITE);
//				}
			}
			
			@Override
			public void mouseClicked(PInputEvent e) {
				super.mouseClicked(e);
				PNode clicked = e.getPickedNode();
				
				if (start == clicked) {
					start.setPaint(Color.WHITE);
					start = null;
					return;
				}
				if (finish == clicked) {
					finish.setPaint(Color.WHITE);
					finish = null;
					return;
				}
				
				if (start == null) {
					start = clicked;
					start.setPaint(Color.GREEN);
				} else if (finish == null) {
					finish = clicked;
					finish.setPaint(Color.BLUE);
				}
				
				
				
				System.out.println("START\t"+start);
				System.out.println("FINISH\t"+finish);
				
			}

			protected void startDrag(PInputEvent e) {
				super.startDrag(e);
				e.setHandled(true);
				e.getPickedNode().moveToFront();
			}

			protected void drag(PInputEvent e) {
				super.drag(e);

				ArrayList edges = (ArrayList) e.getPickedNode().getAttribute(
						"edges");
				for (int i = 0; i < edges.size(); i++) {
					GraphEditor.this.updateEdge((PPath) edges.get(i));
				}
				
				PText name = (PText) e.getPickedNode().getAttribute("name");
				name.translate(400*Math.random(),400*Math.random());
			}
		});
	}

	public void updateEdge(PPath edge) {
		// Note that the node's "FullBounds" must be used
		// (instead of just the "Bounds") because the nodes
		// have non-identity transforms which must be included
		// when determining their position.

		PNode node1 = (PNode) ((ArrayList) edge.getAttribute("nodes")).get(0);
		PNode node2 = (PNode) ((ArrayList) edge.getAttribute("nodes")).get(1);
		Point2D start = node1.getFullBoundsReference().getCenter2D();
		Point2D end = node2.getFullBoundsReference().getCenter2D();
		edge.reset();
		edge.moveTo((float) start.getX(), (float) start.getY());
		edge.lineTo((float) end.getX(), (float) end.getY());
	}
}