Differences

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--- balloons [2018/08/17 08:28] – frchris
+++ balloons [2024/08/25 16:53] (current) – frchris
@@ Line 1: / Line 1: @@
+[[https://archive.org/details/Balloons1.screenflow|Watch old video tutorial]]
 CheckList:
   - Add a method in the ''Balloon'' class called ''rise()'' which is the reverse of ''drop()''
@@ Line 5: / Line 7: @@
   - Change ''keyReleased'' so the new ''Balloon'' is near ''HEIGHT'' rather than 0.
   - Change ''actionPerformed'' so the balloon rises rather than falls
-  - Change ''actionPerformed'' so that it removes the balloon if ''balloons.get(i).getBottom() &lt; 0''
+  - Change ''actionPerformed'' so that it removes the balloon if ''balloons.get(i).getBottom() < 0''
   - Modify the ''paintComponent()'' method to show the number of balloons: ''g.drawString(balloons.size()+" Balloons", WIDTH-100, 20);''
 Challenges:
@@ Line 12: / Line 14: @@
   - Instead of ''Balloon'' objects, have letters drop and have them removed when you type the letter? You can keep score and make it into a game.
-<code java Balloon.java>
+<file java Balloon.java>
 import java.awt.Color;
 import java.awt.Graphics;
@@ Line 47: / Line 49: @@
 }
-</code>
+</file>
 <code java BalloonDrop.java>
+import java.awt.Color;
 import java.awt.Font;
 import java.awt.Graphics;
@@ Line 58: / Line 61: @@
 import java.awt.event.KeyListener;
 import java.util.ArrayList;
 import javax.swing.JFrame;
 import javax.swing.JPanel;
 import javax.swing.Timer;
 public class BalloonFall extends JPanel implements KeyListener, ActionListener
 {
@@ Line 68: / Line 71: @@
 	public static int HEIGHT=600;
     private Font titleFont, regularFont;
-    private ArrayList&lt;Balloon&gt; balloons;
+    private ArrayList<Balloon> balloons;
     private Timer timer;
 	/**
@@ Line 82: / Line 85: @@
     	titleFont = new Font("Roman", Font.BOLD, 18);
     	regularFont = new Font("Helvetica", Font.PLAIN, 12);
-    	balloons = new ArrayList&lt;Balloon&gt;();
+    	balloons = new ArrayList<Balloon>();
     	timer = new Timer(10, this);
         timer.start();
@@ Line 99: / Line 102: @@
 		window.addKeyListener(app);
 		window.setVisible(true);
 	}
 	/**
 	 *  This is the method to change what is drawn to the screen:
@@ Line 119: / Line 122: @@
 			x.draw(g);
 		}
+	}
+/**
+	 * These 3 methods need to be declared to implement the KeyListener Interface
+	 * that listens for keys that are typed on the keyboard
+	 */
+	@Override
+	public void keyTyped(KeyEvent e) {}
+	@Override
+	public void keyPressed(KeyEvent e) {}
+	@Override
+	public void keyReleased(KeyEvent e) {
+		int size = Balloon.randomInt(50, 80);
+		int x = Balloon.randomInt(0, WIDTH);
+		int y = Balloon.randomInt(-size, 0);
+		balloons.add(new Balloon(x,y,size));
+		repaint();
+	}
+	@Override
+	/**
+	 * This method is needed to implement the ActionListener that listens for the timer
+	 * e.getKeyChar () and e.getKeyCode () will return the char (or its code)
+	 */
+	public void actionPerformed ( ActionEvent e) {
+	// timer made an action event, so
+		int i = 0;
+		while ( i < balloons.size() ) {
+			balloons.get(i).drop();
+//
+                        if ( balloons.get(i).getBottom() > HEIGHT ) {
+				balloons.remove (i);
+			}else{
+				i++;
+			}
+		}
+		repaint ();
 	}
 }
 </code>