CS411X - Lecture 9

Lecture Topic:

Main MenuBar Event
Trapping KeyDown Events
FFT
Sample Quiz

process main menubar.java

import java.awt.*;
import java.io.*;
 
class MenuBarFrame extends Frame  {
    MenuBar menuBar;
    String str;
 
    private int JavaIdentifiersMayBeOfUnlimitedLengthTheycanhavenoSpacesNoOperatorsTheyCANHave1234567890NumbersOrDigitsButTheyMustStartWithLetters = 0;
 
    private String science_items [] = {
            "Image Processing","-",
            "Audio Processing",
            "surface",
            "benchmark",
            "-",
            "Toy Calculator"
    };
....
process_menuitem.java
 
 
 
import java.awt.*;
import java.net.*;
 
 
class process_menuitem { 
 
static Grating g = (Grating) Geometry.grating;
static Camera c = (Camera) Geometry.camera;
 
// left af out here so the gc doesn't eat it!
static AudioFrame af; 
static public void objects(MenuBarFrame f, Object arg) {
    // System.out.println("Process_menuitem called with "+arg);
 
    if (arg.equals("Audio Processing")) 
         af = new AudioFrame();
 
    if (arg.equals("htmlGenerator")) {
        HtmlGenerator hg = 
            new HtmlGenerator("The HTML Generator");
            hg.main(null);
        }
 
    if (arg.equals("benchmark")) {
        AppletFrame w = new 
        AppletFrame("BenchmarkApplet");
        String title ="BenchmarkApplet";   ----------->B1
        String args[] ={""};
        w.startApplet("BenchmarkApplet",title,args);
       }

...
...
   public boolean keyDown(Event evt, int key) {
 
       int number_of_shapes;
       Shape  s;
 
 
       int d = Geometry.step_size.getValue(); // mm increment on motion
    point np = new point(0,0);
    point ns = new point(1,1);
       System.out.println("ASCII value: " + key);
       System.out.println("Character: " + (char) key);
       switch (key) {
        case 'd':
            print_dl();
            break;
        case 'a':
            Geometry.print_angles();
            break;
        case 'p':
            Geometry.print();
            break;
        case '6':
            np.x +=d;
            Xform.rmove(np);
            break;
        case '2':
            np.y -=d;
            Xform.rmove(np);
            break;
        case '3':
            np.x +=d;
            np.y -=d;
            Xform.rmove(np);
            break;

--------> B2

If B1 = B2

It would be wonderful, if we can write code, for trapping events only once, and use it in both menu action event and key board action events.

( Z1 Z2 ) = ( a + bi ) ( c + Di )

= ac + aDi + bic + bDi²

= ac - bD + i(aD + bc)

Sample Quiz

1. Class InetAddress