import guicomponents.*;

final int MIN_WIDTH = 50;
final int MAX_WIDTH = 200;
final int MIN_HEIGHT = 50;
final int MAX_HEIGHT = 180;
final int MIN_RADIUS = 20;
final int MAX_RADIUS = 100;

Shape shapeToEdit = null;
boolean mouseEnabled = true;

CircleEditor circleEditor = null;
RectangleEditor rectangleEditor = null;

Shape[] shapes = new Shape[100];
int nbrShapes = 5;

void setup(){
  size(500,400);
  // MUST do this before creating any G4P components
  registerMouseEvent(this);
  // MUST create editors before we create shapes
  circleEditor = new CircleEditor(this);
  rectangleEditor = new RectangleEditor(this);
  // Make some random shapes
  makeRandomShapes();
}

public void makeRandomShapes(){
  int x,y,w,h,r,c;
  for(int i=0; i<nbrShapes; i++){
    x = (int) random(100,width-100);
    y = (int) random(100,height-100);
    w = MIN_WIDTH + (int) random(MAX_WIDTH-MIN_WIDTH);
    h = MIN_HEIGHT + (int) random(MAX_HEIGHT-MIN_HEIGHT);
    r = MIN_RADIUS + (int) random(MAX_RADIUS-MIN_RADIUS);
    c = color(128+random(128), 128+random(128), 128+random(128));
    if(random(1) < 0.5)
	shapes[i] = new Rectangle(this,x,y,w,h,c);
    else
	shapes[i] = new Circle(this,x,y,r,c);
  }
}

/*
  * DO NOT USE the methods
  * mouseClicked(), mousePressed(), mouseDragged(), mouseReleased()
  * these methods remove the actual mouse event from the event queue
  * which means it is no longer available to G4P methods.
  * Instead use this method.
  */
void mouseEvent(MouseEvent event){
  // If a shape has been selected
  if(shapeToEdit != null) return;
  switch(event.getID()){
  case MouseEvent.MOUSE_PRESSED:
    break;
  case MouseEvent.MOUSE_CLICKED:
    handleMouseClick();
    break;
  case MouseEvent.MOUSE_RELEASED:
    break;
  case MouseEvent.MOUSE_DRAGGED:
    break;
  }
}

/*
 * Loop through all the shapes in reverse draw order and see
 * whether we have clicked on a shape. If we have then open
 * the correct editor
 */
public void handleMouseClick(){
  String shapeType = null;
  Shape shpaeClicked;
  for(int i=nbrShapes-1; i>=0; i--){
    if(shapes[i].isInside(mouseX, mouseY)){
	shapeToEdit = shapes[i];
	shapeType = shapeToEdit.getClass().getSimpleName();
	break;
    }
  }
  if(shapeType != null){
    if(shapeType.equalsIgnoreCase("Circle")){
	circleEditor.initForCircle((Circle) shapeToEdit);
    }
    else if(shapeType.equalsIgnoreCase("Rectangle")){
	rectangleEditor.initForRectangle((Rectangle) shapeToEdit);
    }
  }
}

/*
 * You must surround your drawing commands with pushStyle()
 * and popStyle() with this version of G4P. 
 * This will not be necessary with the next release V1.3
 */
public void draw(){
  background(240);
  pushStyle();
  for(int i=0; i<nbrShapes; i++){
    shapes[i].display();
  }
  popStyle();
}


/**
  * Parent class for all your different types of shape
  */
abstract class Shape {
  protected PApplet app;
  // Centre of the shape
  public int cx;
  public int cy;
  // Fill colour
  public int fillColor;

  // Override this method in child classes
  // returns true if the position x,y is 
  // inside the shape
  abstract public boolean isInside(int x, int y);

  // Override this method in child classes
  // displays the shape - should be called from draw() method
  abstract public void display();
}
/**
 * The rectangle class
 */
class Rectangle extends Shape {
  public int width;
  public int height;

  Rectangle(PApplet theApplet, int x, int y, int w, int h, int col){
    app = theApplet;
    cx = x;
    cy = y;
    width = w;
    height = h;
    fillColor = col;
  }

  public boolean isInside(int x, int y){
    return  (abs(cx-x) <= width/2) && (abs(cy-y) < height/2);
  }
  public void display(){
    rectMode(CENTER);
    fill(fillColor);
    rect(cx,cy,width,height);
  }
}

/**
 * The circle claas 
 */
class Circle extends Shape {
  public int radius;

  Circle(PApplet theApplet, int x, int y, int r, int col){
    app = theApplet;
    cx = x;
    cy = y;
    radius = r;
    fillColor = col;
  }
  public boolean isInside(int x, int y){
    return ( (int)dist(cx,cy,x,y) <= radius);
  }
  public void display(){
    ellipseMode(CENTER);
    fill(fillColor);
    ellipse(cx,cy,2*radius,2*radius);
  }
}
 

txf1!="" 

if( txf1!=null && !txf1.getText().equals("")) { 

testFloatX = Float.parseFloat(txf1.getText()); 

public void handleTextFieldEvents(GTextField tfield){
   if(tfield == txf1){
     
     switch (txf1.getEventType()){
     case GTextField.CHANGED:

       print("CHANGED");

       if( txf1!=null && !txf1.getText().equals("")) {
         try{
            // See if the text field holds a number
            testFloatX = Float.parseFloat(txf1.getText());
            // if it failed then goto catch clause below
            // if no problem then move the rectangle.
            ((Rectangle)shapeToEdit).positionX = testFloatX;
         }
         catch(Exception e){
            // We get here if the text in the txf1 
            // cannot be converted to a number
         }
         break;     
     } // end of switch statement
                     
       ...