Java2实用教程(第二版)程序代码——第十一章 面板和画布
1
//例子1
2
import java.applet.*;import java.awt.*;import java.awt.event.*;
3
class Mypanel extends Panel implements ActionListener
4
{ Button button1,button2,button3;
5
Color backColor;
6
Mypanel() //构造方法。当创建面板对象时,面板被初始化为有三个按钮。
7
{ button1=new Button("确定");button2=new Button("取消");button3=new Button("保存");
8
add(button1);add(button2);add(button3);
9
setBackground(Color.pink); //设置面板的底色。
10
backColor=getBackground(); //获取底色。
11
button1.addActionListener(this);button2.addActionListener(this);
12
}
13
public void actionPerformed(ActionEvent e)
14
{ if(e.getSource()==button1)
15
{ setBackground(Color.cyan);
16
}
17
else if(e.getSource()==button2)
18
{ setBackground(backColor);
19
}
20
}
21
}
22
public class Example11_1 extends Applet
23
{ Mypanel panel1,panel2,panel3;
24
Button button;
25
public void init()
26
{ panel1=new Mypanel();panel2=new Mypanel();panel3=new Mypanel();
27
button=new Button("我不在那些面板里");
28
add(panel1);add(panel2);add(panel3);
29
add(button);
30
}
31
}
32![](/Images/OutliningIndicators/None.gif)
33
//例子2
34
import java.awt.*;import java.applet.*;
35
public class Example11_2 extends Applet
36
{ Panel p ;
37
ScrollPane scrollpane;
38
public void init()
39
{ p=new Panel();
40
scrollpane=new ScrollPane(ScrollPane.SCROLLBARS_ALWAYS);
41
p.add(new Button("one"));p.add(new Button("two"));
42
p.add(new Button("three"));p.add(new Button("four"));
43
scrollpane.add(p);//scrollpane添加一个面板。
44
add(scrollpane);//小程序添加滚动窗口。
45
}
46
}
47![](/Images/OutliningIndicators/None.gif)
48
//例子3
49
import java.awt.*;import java.applet.*;
50
class Mycanvas extends Canvas
51
{ String s;
52
Mycanvas(String s)
53
{ this.s=s;
54
setSize(90,80);
55
setBackground(Color.cyan);
56
}
57
public void paint(Graphics g)
58
{ if(s.equals("circle"))
59
g.drawOval(20,25,30,30);
60
else if(s.equals("rect"))
61
g.drawRect(30,35,20,20);
62
}
63
}
64
public class Example11_3 extends Applet
65
{ Mycanvas canvas1,canvas2;
66
public void init()
67
{ canvas1=new Mycanvas("circle");canvas2=new Mycanvas("rect");
68
add(canvas1);
69
Panel p=new Panel();p.setBackground(Color.pink);
70
p.add(canvas2) ;
71
add(p);
72
}
73
}
74![](/Images/OutliningIndicators/None.gif)
75
//例子4
76
import java.awt.*;
77
import java.applet.*;
78
import java.awt.event.*;
79
class Mycanvas extends Canvas
80
{ int x,y,r;
81
int red,green,blue;
82
Mycanvas()
83
{ setSize(100,100);
84
setBackground(Color.cyan);
85
}
86
public void setX(int x)
87
{ this.x=x;
88
}
89
public void setY(int y)
90
{ this.y=y;
91
}
92
public void setR(int r)
93
{ this.r=r;
94
}
95
public void paint(Graphics g)
96
{ g.drawOval(x,y,2*r,2*r);
97
}
98
}
99
public class Example11_4 extends Applet implements ActionListener
100
{ Mycanvas canvas;
101
TextField inputR,inputX,inputY;
102
Button b;
103
public void init()
104
{ canvas=new Mycanvas();
105
inputR=new TextField(6);
106
inputX=new TextField(6);
107
inputY=new TextField(6);
108
add(new Label("输入圆的位置坐标:"));
109
add(inputX);
110
add(inputY);
111
add(new Label("输入圆的半径:"));
112
add(inputR);
113
b=new Button("确定");
114
b.addActionListener(this);
115
add(b);
116
add(canvas);
117
}
118
public void actionPerformed(ActionEvent e)
119
{ int x,y,r;
120
try {
121
x=Integer.parseInt(inputX.getText());
122
y=Integer.parseInt(inputY.getText());
123
r=Integer.parseInt(inputR.getText());
124
canvas.setX(x);
125
canvas.setY(y);
126
canvas.setR(r);
127
canvas.repaint();
128
}
129
catch(NumberFormatException ee)
130
{
131
x=0;y=0;r=0;
132
}
133
}
134
}
135![](/Images/OutliningIndicators/None.gif)
![](/Images/OutliningIndicators/None.gif)
2
![](/Images/OutliningIndicators/None.gif)
3
![](/Images/OutliningIndicators/None.gif)
4
![](/Images/OutliningIndicators/ExpandedBlockStart.gif)
5
![](/Images/OutliningIndicators/InBlock.gif)
6
![](/Images/OutliningIndicators/InBlock.gif)
7
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
8
![](/Images/OutliningIndicators/InBlock.gif)
9
![](/Images/OutliningIndicators/InBlock.gif)
10
![](/Images/OutliningIndicators/InBlock.gif)
11
![](/Images/OutliningIndicators/InBlock.gif)
12
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
13
![](/Images/OutliningIndicators/InBlock.gif)
14
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
15
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
16
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
17
![](/Images/OutliningIndicators/InBlock.gif)
18
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
19
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
20
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
21
![](/Images/OutliningIndicators/ExpandedBlockEnd.gif)
22
![](/Images/OutliningIndicators/None.gif)
23
![](/Images/OutliningIndicators/ExpandedBlockStart.gif)
24
![](/Images/OutliningIndicators/InBlock.gif)
25
![](/Images/OutliningIndicators/InBlock.gif)
26
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
27
![](/Images/OutliningIndicators/InBlock.gif)
28
![](/Images/OutliningIndicators/InBlock.gif)
29
![](/Images/OutliningIndicators/InBlock.gif)
30
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
31
![](/Images/OutliningIndicators/ExpandedBlockEnd.gif)
32
![](/Images/OutliningIndicators/None.gif)
33
![](/Images/OutliningIndicators/None.gif)
34
![](/Images/OutliningIndicators/None.gif)
35
![](/Images/OutliningIndicators/None.gif)
36
![](/Images/OutliningIndicators/ExpandedBlockStart.gif)
37
![](/Images/OutliningIndicators/InBlock.gif)
38
![](/Images/OutliningIndicators/InBlock.gif)
39
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
40
![](/Images/OutliningIndicators/InBlock.gif)
41
![](/Images/OutliningIndicators/InBlock.gif)
42
![](/Images/OutliningIndicators/InBlock.gif)
43
![](/Images/OutliningIndicators/InBlock.gif)
44
![](/Images/OutliningIndicators/InBlock.gif)
45
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
46
![](/Images/OutliningIndicators/ExpandedBlockEnd.gif)
47
![](/Images/OutliningIndicators/None.gif)
48
![](/Images/OutliningIndicators/None.gif)
49
![](/Images/OutliningIndicators/None.gif)
50
![](/Images/OutliningIndicators/None.gif)
51
![](/Images/OutliningIndicators/ExpandedBlockStart.gif)
52
![](/Images/OutliningIndicators/InBlock.gif)
53
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
54
![](/Images/OutliningIndicators/InBlock.gif)
55
![](/Images/OutliningIndicators/InBlock.gif)
56
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
57
![](/Images/OutliningIndicators/InBlock.gif)
58
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
59
![](/Images/OutliningIndicators/InBlock.gif)
60
![](/Images/OutliningIndicators/InBlock.gif)
61
![](/Images/OutliningIndicators/InBlock.gif)
62
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
63
![](/Images/OutliningIndicators/ExpandedBlockEnd.gif)
64
![](/Images/OutliningIndicators/None.gif)
65
![](/Images/OutliningIndicators/ExpandedBlockStart.gif)
66
![](/Images/OutliningIndicators/InBlock.gif)
67
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
68
![](/Images/OutliningIndicators/InBlock.gif)
69
![](/Images/OutliningIndicators/InBlock.gif)
70
![](/Images/OutliningIndicators/InBlock.gif)
71
![](/Images/OutliningIndicators/InBlock.gif)
72
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
73
![](/Images/OutliningIndicators/ExpandedBlockEnd.gif)
74
![](/Images/OutliningIndicators/None.gif)
75
![](/Images/OutliningIndicators/None.gif)
76
![](/Images/OutliningIndicators/None.gif)
77
![](/Images/OutliningIndicators/None.gif)
78
![](/Images/OutliningIndicators/None.gif)
79
![](/Images/OutliningIndicators/None.gif)
80
![](/Images/OutliningIndicators/ExpandedBlockStart.gif)
81
![](/Images/OutliningIndicators/InBlock.gif)
82
![](/Images/OutliningIndicators/InBlock.gif)
83
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
84
![](/Images/OutliningIndicators/InBlock.gif)
85
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
86
![](/Images/OutliningIndicators/InBlock.gif)
87
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
88
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
89
![](/Images/OutliningIndicators/InBlock.gif)
90
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
91
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
92
![](/Images/OutliningIndicators/InBlock.gif)
93
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
94
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
95
![](/Images/OutliningIndicators/InBlock.gif)
96
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
97
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
98
![](/Images/OutliningIndicators/ExpandedBlockEnd.gif)
99
![](/Images/OutliningIndicators/None.gif)
100
![](/Images/OutliningIndicators/ExpandedBlockStart.gif)
101
![](/Images/OutliningIndicators/InBlock.gif)
102
![](/Images/OutliningIndicators/InBlock.gif)
103
![](/Images/OutliningIndicators/InBlock.gif)
104
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
105
![](/Images/OutliningIndicators/InBlock.gif)
106
![](/Images/OutliningIndicators/InBlock.gif)
107
![](/Images/OutliningIndicators/InBlock.gif)
108
![](/Images/OutliningIndicators/InBlock.gif)
109
![](/Images/OutliningIndicators/InBlock.gif)
110
![](/Images/OutliningIndicators/InBlock.gif)
111
![](/Images/OutliningIndicators/InBlock.gif)
112
![](/Images/OutliningIndicators/InBlock.gif)
113
![](/Images/OutliningIndicators/InBlock.gif)
114
![](/Images/OutliningIndicators/InBlock.gif)
115
![](/Images/OutliningIndicators/InBlock.gif)
116
![](/Images/OutliningIndicators/InBlock.gif)
117
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
118
![](/Images/OutliningIndicators/InBlock.gif)
119
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
120
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
121
![](/Images/OutliningIndicators/InBlock.gif)
122
![](/Images/OutliningIndicators/InBlock.gif)
123
![](/Images/OutliningIndicators/InBlock.gif)
124
![](/Images/OutliningIndicators/InBlock.gif)
125
![](/Images/OutliningIndicators/InBlock.gif)
126
![](/Images/OutliningIndicators/InBlock.gif)
127
![](/Images/OutliningIndicators/InBlock.gif)
128
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
129
![](/Images/OutliningIndicators/InBlock.gif)
130
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
131
![](/Images/OutliningIndicators/InBlock.gif)
132
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
133
![](/Images/OutliningIndicators/ExpandedSubBlockEnd.gif)
134
![](/Images/OutliningIndicators/ExpandedBlockEnd.gif)
135
![](/Images/OutliningIndicators/None.gif)