PaintPanel.java

/*
 * Name: Thomas Cheng
 * 
 * Date: July 22, 2018
 * 
 * Dsscription: This is the PaintPanel class that will draw all the shapes.
 */

import javax.swing.JPanel;
import javax.swing.JLabel;

import java.awt.Graphics;
import java.awt.GradientPaint;
import java.awt.Color;
import java.awt.BorderLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

public class PaintPanel extends JPanel {
 // instance variables
 private LinkedList<Shape> shapeList;
 private DynamicStack<Shape> redoStack;
 private JLabel statusLabel;
 private Shape currentShape = null;
 private int shapeType;
 private Color colourOne;
 private Color colourTwo;
 private boolean isFilled;
 private boolean isGradient;
 private double lineSize;
 private boolean isDashLine;
 private double dashLineLength;
 
 /* This is the constructor method for the class. This method accepts 1 parameter: a reference to a JLabel object.
 */
 public PaintPanel( JLabel statusLabel ) {
 super();
 setLayout( new BorderLayout() );
 shapeList = new LinkedList<Shape>();
 redoStack = new DynamicStack<Shape>();
 this.statusLabel = statusLabel;
 
 // Create and register listener for mouse and mouse motion events
 MouseEventListener drawFrameListener = new MouseEventListener(); 
 addMouseListener( drawFrameListener ); 
 addMouseMotionListener( drawFrameListener ); 
 }
 
 /* This inner class handles mouse events.
 */
 class MouseEventListener extends MouseAdapter {
 /* This method checks for a mouse press to indicate a new shape has been started. This method accepts 1
 * parameter: a reference to a MouseEvent object. This method returns no values.
 */
 @Override
 public void mousePressed( MouseEvent event ) {
 // draws the specificed shape
 // draw a line
 if (currentShape == null){
 if ( shapeType == 0 ){
 currentShape = new Line( event.getX(), event.getY(), event.getX(), event.getY(), colourOne, 
 colourTwo, isGradient, lineSize );
 }
 // draw a rectangle
 else if ( shapeType == 1 ){
 currentShape = new Rectangle( event.getX(), event.getY(), event.getX(), event.getY(), 
 colourOne, colourTwo, isGradient, isFilled, lineSize );
 }
 // draw an oval
 else if ( shapeType == 2 ){
 currentShape = new Oval( event.getX(), event.getY(), event.getX(), event.getY(), 
 colourOne, colourTwo, isGradient, isFilled, lineSize);
 }
 // Tell JVM to call paintComponent( g )
 repaint();
 }
 } 
 
 /* This method checks for a mouse release to indicate the shape has been finished. This method accepts 1
 * parameter: a reference to a MouseEvent object. This method returns no values.
 */
 @Override
 public void mouseReleased( MouseEvent event ) {
 // Update ending coordinates
 if (currentShape != null){
 currentShape.setX2( event.getX() );
 currentShape.setY2( event.getY() );
 currentShape.setColourOne( colourOne );
 
 // add the new shape to the END of the LinkedList
 shapeList.addLast( currentShape );
 
 // Get ready for the next line to be drawn
 currentShape = null;
 repaint();
 
 // clear the redo stack
 redoStack.clear();
 }
 } 
 
 /* This method updates the ending coordinates of currentShape and statusLabel as the mouse is dragged. 
 * This method accepts 1 parameter: a reference to a MouseEvent object. This method returns no values.
 */
 @Override
 public void mouseDragged( MouseEvent event ) {
 if (currentShape != null){
 currentShape.setX2( event.getX() );
 currentShape.setY2( event.getY() );
 statusLabel.setText( String.format( "(%d, %d)", event.getX(), event.getY() ) );
 repaint();
 }
 } 
 
 /* This method updates the statusLabel as the mouse is moved. This method accepts 1 parameter: a reference to 
 * a MouseEvent object. This method returns no values.
 */
 @Override
 public void mouseMoved( MouseEvent event ) {
 statusLabel.setText( String.format( "(%d, %d)", event.getX(), event.getY() ) );
 } 
 } 
 
 /* This method is called automatically by the JVM when the window needs to be (re)drawn. This methid accepts 1
 * parameter: a reference to a Graphics object. This method returns no values.
 */
 @Override
 public void paintComponent( Graphics g ) {
 super.paintComponent( g );
 removeAll();
 // Call the draw() method for each Line object in the array
 for ( int index = 0; index < shapeList.size(); index++ ){
 Shape shape = shapeList.removeFirst();
 shape.draw( g );
 shapeList.addLast( shape );
 }
 
 // If a line is in progress, draw it on top of all others
 if ( currentShape != null )
 currentShape.draw( g );
 }
 
 /* This method will remove the last element in shapeList if it isn't empty, push it to redoStack,
 * and call repaint(). This method accepts and returns no values.
 */
 public void undo() {
 if ( !( shapeList.isEmpty() ) ){
 redoStack.push( shapeList.removeLast() );
 repaint();
 }
 }
 
 /* This method will pop the first element in redoStack if it isn't empty, add it to the end of shapeList,
 * and call repaint(). This method accepts and returns no values.
 */
 public void redo() {
 if ( !( redoStack.isEmpty() ) ){
 shapeList.addLast( redoStack.pop() );
 repaint();
 }
 }
 
 /* This method will call the clear method for both shapeList and redoStack, and call repaint(). 
 * This method accepts and returns no values.
 */
 public void clear() {
 shapeList.clear();
 redoStack.clear();
 repaint();
 }
 
 /* This is the mutator method for shapeType. This method accepts 1 parameter: an integer value representing the
 * type of shape the user wants to draw. This method returns no values.
 */
 public void setShapeType( int shapeType ) {
 this.shapeType = shapeType;
 }
 
 /* This is the mutator method for currentColor. This method accepts 1 parameter: a reference to a Color object.
 * This method returns no values.
 */
 public void setColourOne( Color colour ) {
 colourOne = colour;
 }
 
 public void setColourTwo( Color colour ) {
 colourTwo = colour;
 }
 
 /* This is the mutator method for isFilled. This method accepts 1 parameter: an boolean value representing whether
 * the shape is filled or not. This method returns no values.
 */
 public void setFill( boolean isFilled ) {
 this.isFilled = isFilled;
 }
 
 public void setIsGradient( boolean isGradient ) {
 this.isGradient = isGradient;
 }
 
 public void setLineSize( double lineSize ){
 this.lineSize = lineSize;
 }
 
 public void setLineStyle( ) {
 }
 
 public void setDashLineLength( double dashLineLength ) {
 this.dashLineLength = dashLineLength;
 }
}