Tips for using jscrollbar

Jscrollbar has two common constructor methods.

1. jscrollbar1 = new jscrollbar ();

Create a scroll bar with the specified direction and the following initial values:

Minimum = 0
Maximum= 100
Value = 0
Extent = 10

2. jscrollbar2 = new jscrollbar (INT orientation, int value, int extent, int min, int max );

The parameters are as follows:

1 is horizontal or vertical, which can be:

Jscrollbar. Horizontal or: jscrollbar. Vertical

2 Initial Value

3. Expand the size of the scroll bar to reach the max-extent. For example, if the maximum value is 100 and the extend value is 10, the scroll bar can reach the maximum value of 90.

4 min

5 max

Below is

The first is the default constructor, and the second is the constructor.

Jscrollbar3 = new jscrollbar (jscrollbar. Horizontal ,);

You can see that the scroll bar of the default constructor can only reach 90

An important method is: jscrollbar1.getvalue ()

Set the maximum and minimum values:

{

Jscrollbar1.setminimum (int I );
Jscrollbar1.setmaximum (int I );

}

The internal class implements adjustmentlistener to monitor the value changes of the jscrollbar;

1. Jscrollbar1.addadjustmentlistener (New adjustmentlistener ()
2. {
3. Public void adjustmentvaluechanged (adjustmentevent EVT ){
4. Jtextfield1.settext (string. valueof ("the current value of the scroll bar is:" + jscrollbar1.getvalue ()));
5. }
6. });

Below is the source code, you can try to change it

1. Import java. AWT. event .*;
2. Import javax. Swing .*;
3. Public class newjframes extends javax. Swing. jframe {
4. Private Static final long serialversionuid = 1l;
5. Private jtextfield jtextfield1;
6. Private jlabel jlabel2;
7. Private jbutton jbutton1;
8. Private jscrollbar jscrollbar3;
9. Private jlabel jlabel1;
10. Private jtextfield jtextfield3;
11. Private jtextfield jtextfield2;
12. Private jscrollbar jscrollbar1;
14. Public static void main (string [] ARGs ){
15. Swingutilities. invokelater (New runnable ()
16. {
17. Public void run (){
18. Newjframes inst = new newjframes ();
19. Inst. setlocationrelativeto (null );
20. Inst. setvisible (true );
21. }
22. });
23. }
25. Public newjframes (){
26. Super ();
27. Initgui ();
28. }
30. Private void initgui (){
31. Try {
32. Setdefaclocloseoperation (windowconstants. dispose_on_close );
33. Getcontentpane (). setlayout (null );
34. Settitle ("scroll bar test ");
35. {
36. Jscrollbar3 = new jscrollbar (jscrollbar. Horizontal );
37. Getcontentpane (). Add (jscrollbar3 );
38. Jscrollbar3.setbounds (12,220,358, 34 );
39. Jscrollbar3.addadjustmentlistener (New adjustmentlistener ()
40. {
41. Public void adjustmentvaluechanged (adjustmentevent EVT ){
42. Jtextfield1.settext (string. valueof ("the current value of the scroll bar is:" + jscrollbar3.getvalue ()));
43. }
44. });
45. }
46. {
47. Jscrollbar1 = new jscrollbar ();
48. Getcontentpane (). Add (jscrollbar1 );
49. Jscrollbar1.setbounds );
50. Jscrollbar1.setorientation (swingconstants. Horizontal );
51. Jscrollbar1.addadjustmentlistener (New adjustmentlistener ()
52. {
53. Public void adjustmentvaluechanged (adjustmentevent EVT ){
54. Jtextfield1.settext (string. valueof ("the current value of the scroll bar is:" + jscrollbar1.getvalue ()));
55. }
56. });
57. }
58. {
59. Jtextfield1 = new jtextfield ();
60. Getcontentpane (). Add (jtextfield1 );
61. Jtextfield1.setbounds (242,5, 138,26 );
62. }
63. {
64. Jtextfield2 = new jtextfield ();
65. Getcontentpane (). Add (jtextfield2 );
66. Jtextfield2.setbounds );
67. }
68. {
69. Jtextfield3 = new jtextfield ();
70. Getcontentpane (). Add (jtextfield3 );
71. Jtextfield3.setbounds );
72. }
73. {
74. Jlabel1 = new jlabel ();
75. Getcontentpane (). Add (jlabel1 );
76. Jlabel1.settext ("set minimum value ");
77. Jlabel1.setbounds );
78. }
79. {
80. Jlabel2 = new jlabel ();
81. Getcontentpane (). Add (jlabel2 );
82. Jlabel2.settext ("set maximum value ");
83. Jlabel2.setbounds (12, 78, 80, 25 );
84. }
85. {
86. Jbutton1 = new jbutton ();
87. Getcontentpane (). Add (jbutton1 );
88. Jbutton1.settext ("set ");
89. Jbutton1.setbounds (123,128, 22 );
90. Jbutton1.addactionlistener (New actionlistener ()
91. {
92. Public void actionreceivmed (actionevent EVT ){
93. If (jtextfield2.gettext (). isempty () | jtextfield3.gettext (). isempty ()){
94. Jscrollbar1.setvalue (jscrollbar1.getvalue () + 1 );
95. } Else {
96. Jscrollbar1.setminimum (integer. valueof (jtextfield2.gettext ()));
97. Jscrollbar1.setmaximum (integer. valueof (jtextfield3.gettext ()));
98. }
99. }
100. });
101. }
103. Pack ();
104. Setsize (400,300 );
105. } Catch (exception e ){
106. E. printstacktrace ();
107. }
108. }
109. }