1 /* File: PictureTime.java
2 *
3 * This example illustrates the hierarchical use
4 * of components in a grid layout.
5 * This version uses Java 1.1 event model.
6 * New version with colored circles on the canvas by Mehmet Sen 10/97.
7 */
8
9 import java.awt.*;
10 import java.awt.event.*;
11
12 public class PictureTime extends java.applet.Applet {
13
14 /* instance variable to hold the subpanel component */
15 ControlPanel control;
16
17 /* instance variable to hold the canvas component */
18 Display displaycanvas;
19
20
21 public void init() {
22
23 /* using Border layout with gap of 5 points separating each component */
24 setLayout(new BorderLayout(5,5));
25 setBackground(Color.orange);
26 displaycanvas = new Display(0); /* creating the canvas component */
27 displaycanvas.setBackground(Color.blue);
28 displaycanvas.start();
29
30 /* creating instance for PictureControl panel */
31 control = new ControlPanel(this);
32
33 /* adding the components to the panel */
34 add(displaycanvas,BorderLayout.CENTER);
35 add(control,BorderLayout.NORTH);
36 }
37
38
39 void changeCanvasColor(String category) {
40 if (category.equals("Button 1"))
41 displaycanvas.draw(1,Color.green);
42 else if (category.equals("Button 2"))
43 displaycanvas.draw(2,Color.cyan);
44 else if (category.equals("Button 3"))
45 displaycanvas.draw(3,Color.pink);
46 else displaycanvas.draw(0,Color.black);
47 }
48 }
49
50 //_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
51 /* this class is a subclass of Panel */
52 //_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
53 class ControlPanel extends Panel implements ActionListener
54 {
55 /* instance variable to hold a pointer to calling class */
56 PictureTime outerparent;
57
58 /* the three control buttons */
59 Button b1,b2,b3;
60
61 ControlPanel(PictureTime target) {
62 this.outerparent = target;
63 Font font = new Font("SansSerif",Font.BOLD,16);
64
65 setLayout(new GridLayout(1,3,10,0));
66 setBackground(Color.orange);
67
68 /* putting the buttons */
69 b1=new Button("Button 1");
70 add(b1);
71 b1.setForeground(Color.black);
72 b1.setFont(font);
73 b1.setBackground(Color.green);
74 b1.addActionListener(this);
75
76 b2=new Button("Button 2");
77 add(b2);
78 b2.setForeground(Color.blue);
79 b2.setBackground(Color.cyan);
80 b2.addActionListener(this);
81 b2.setFont(font);
82
83 b3=new Button("Button 3");
84 add(b3);
85 b3.setForeground(Color.black);
86 b3.setBackground(Color.pink);
87 b3.addActionListener(this);
88 b3.setFont(font);
89 }
90
91 public void actionPerformed(ActionEvent evt) {
92 /* getActionCommand will return label of the button clicked
93 or we could have used getSource() to return pointer to the button,
94 i.e. either t, d, or s */
95 String label = evt.getActionCommand();
96 this.outerparent.changeCanvasColor(label);
97 }
98 }
99
100 //_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
101 // Display canvas show animated little balls from left towards pressed buton
102 //_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
103 class Display extends Canvas implements Runnable
104 {
105 int Target;
106 Thread animate;
107 Display(int _target)
108 {
109 Target=_target;
110 }
111 public void draw(int _target,Color bg) {
112 setBackground(bg);
113 Target=_target;
114 repaint();
115 }
116 public void start() {
117 if (animate==null){
118 animate=new Thread(this);
119 animate.start();
120 }
121 }
122 public void stop() {
123 if (animate!=null){
124 animate.stop();
125 animate=null;
126 }
127 }
128
129 public void run() {
130 while(true){
131 try {
132 Thread.sleep(100);
133 }
134 catch (InterruptedException e) {
135 }
136 repaint();
137 }
138 }
139
140 public void paint(Graphics g)
141 {
142 int X,Y,source_x,source_y,target_x,target_y;
143 int h=20;
144 int w=20;
145 int i=0;
146 int step=h*4/3;
147 X=getSize().width;
148 Y=getSize().height;
149 source_x=X/3;
150 source_y=Y-20;
151 target_x=X/6+(X/3)*(Target-1);
152 target_y=-20;
153 for (i=source_y;i>Y*8/9;i-=step+8){
154 g.setColor(Color.black);
155 g.fillOval(source_x-5,i-5,w+10,h+10);
156 g.setColor(new Color((float)Math.random(),(float)Math.random(),(float)Math.random()));
157 g.fillOval(source_x,i,w,h);
158 }
159 for (int y=i,x=source_x;y>target_y;){
160 g.setColor(Color.black);
161 g.fillOval(x-5,y-5,w+10,h+10);
162 g.setColor(new Color((float)Math.random(),(float)Math.random(),(float)Math.random()));
163 g.fillOval(x,y,w,h);
164 if(y>target_y) y-=step;
165 if((x<target_x+15)&&(x>target_x-15)) y-=8;
166 else if(x<target_x) x+=step;
167 else x-=step;
168 }
169 }
170
171 }
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