sketcher.java

Beginning Java 2, SDK 1.4 Edition Exercise Code samples for this book

// Chapter 20 Exercise 5
// Use a book object to draw a sketch spread over four pages when it is printed.
/*
  The additional code to do this is in the actionPerformed() method in the FileAction
  inner class to the SkecthFrame class. The print() and getNumberOfPages() methods
  in SketchView are as in the solution to the previous exercise.
  
  The actionPerformed() method also has commented out code to illustrate how you might
  modify the Paper object.

*/
// Sketching application
import java.awt.Dimension;
import java.awt.Toolkit;

import java.awt.event.WindowEvent;
import java.awt.event.WindowAdapter;

import java.awt.BorderLayout;
import java.util.Observer;

public class Sketcher {

  public static void main(String[] args) {
    theApp = new Sketcher();              // Create the application object
    theApp.init();                        // ...and initialize it
  }

  public void init() {
    window = new SketchFrame("Sketcher", this);    // Create the app window
    Toolkit theKit = window.getToolkit();        // Get the window toolkit
    Dimension wndSize = theKit.getScreenSize();  // Get screen size

    // Set the position to screen center & size to half screen size
    window.setBounds(wndSize.width/4, wndSize.height/4,        // Position
                     wndSize.width/2, wndSize.height/2);       // Size

    window.addWindowListener(new WindowHandler());  // Add window listener
    sketch = new SketchModel();               // Create the model
    view = new SketchView(this);              // Create the view
    sketch.addObserver((Observer)view);       // Register the view with the model
    sketch.addObserver(window);              // Register window as observer
    
    window.getContentPane().add(view, BorderLayout.CENTER);
    window.setVisible(true);
  }

  public void insertModel(SketchModel newSketch) {
    sketch = newSketch;                          // Store the new sketch
    sketch.addObserver((Observer)view);          // Add the view as observer
    sketch.addObserver((Observer)window);        // Add the app window as
                                                 // observer
    view.repaint();                              // Repaint the view
  }  

  // Return a reference to the application window
  public SketchFrame getWindow() { 
     return window; 
  }

  // Return a reference to the model
  public SketchModel getModel() { 
     return sketch; 
  }

  // Return a reference to the view
  public SketchView getView() { 
     return view; 
  }

  // Handler class for window events
  class WindowHandler extends WindowAdapter {
    // Handler for window closing event
    public void windowClosing(WindowEvent e) {
      window.checkForSave();
    }
  }

  private SketchModel sketch;                     // The data model for the sketch
  private SketchView view;                        // The view of the sketch
  private static SketchFrame window;              // The application window
  private static Sketcher theApp;                 // The application object
}