java JScrollBar不工作
我正在尝试将JScrollPane
添加到JTextArea
,但是当我添加它时,JPane
不再显示我的textarea
。如果没有JScrollPane
,它会显示它,但是我无法显示从文件检索到的所有信息
这是我想用JScrollPane
包装的textArea
之一的代码
public GUI_CWK()
{
//frame details
setSize(450,400);
setLayout(null);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle("H.o. | Location Database");
setExtendedState(JFrame.MAXIMIZED_BOTH);
getContentPane().setBackground(Color.YELLOW);
// Useing Lable to set a title for multiple buttons
lbl2 = new JLabel();
lbl2.setSize(420,85);
lbl2.setLocation(15,0);
lbl2.setEnabled(false);
lbl2.setFont(new Font ("arial",5,17));
lbl2.setText("Options to Manipulate with Data");
add(lbl2);
// Adding buttons to JFrame
btn1 = new JButton("Add new entry");
btn1.setSize(120,20);
btn1.setLocation(7,80);
btn1.addActionListener(this);
add(btn1);
btn2 = new JButton("Search");
btn2.setSize(120,20);
btn2.setLocation(7,110);
btn2.addActionListener(this);
add(btn2);
btn3 = new JButton("Update Entry");
btn3.setSize(120,20);
btn3.setLocation(150,110);
btn3.addActionListener(this);
add(btn3);
btn4 = new JButton("Print All");
btn4.setSize(120,20);
btn4.setLocation(150,80);
btn4.addActionListener(this);
add(btn4);
btn5 = new JButton("Print Arrays");
btn5.setSize(120,20);
btn5.setLocation(7,140);
btn5.addActionListener(this);
add(btn5);
btn6 = new JButton("Delete Entry");
btn6.setSize(120,20);
btn6.setLocation(300,80);
btn6.addActionListener(this);
add(btn6);
btn7 = new JButton("Delete ALL");
btn7.setSize(120,20);
btn7.setLocation(300,110);
btn7.addActionListener(this);
add(btn7);
lbl1 = new JLabel();
lbl1.setSize(420,85);
lbl1.setLocation(15,190);
lbl1.setEnabled(false);
lbl1.setFont(new Font ("arial",5,17));
lbl1.setText("Extra Options");
add(lbl1);
btn8 = new JButton("Sort Data");
btn8.setSize(160,20);
btn8.setLocation(7,265);
btn8.addActionListener(this);
add(btn8);
btn9 = new JButton("Open Text file");
btn9.setSize(160,20);
btn9.setLocation(7,300);
btn9.addActionListener(this);
add(btn9);
btn11 = new JButton("Retrieve from text file");
btn11.setSize(160,20);
btn11.setLocation(240,265);
btn11.addActionListener(this);
add(btn11);
btn12 = new JButton("Exit Program");
btn12.setSize(160,20);
btn12.setLocation(240,300);
btn12.addActionListener(this);
add(btn12);
lbl3 = new JLabel();
lbl3.setSize(420,85);
lbl3.setLocation(15,340);
lbl3.setEnabled(false);
lbl3.setFont(new Font ("arial",5,17));
lbl3.setText("Terminal Window");
add(lbl3);
// Adding textArea to display each user entered value
textArea2 = new JTextArea(5, 20);
textArea2.setEditable(false);
textArea2.setSize(440,300);
textArea2.setLocation(7,400);
textArea2.setDisabledTextColor(Color.black);
textArea2.setFont(new Font("arial",5,14));
sp2 = new JScrollPane(textArea2);
sp2.setVerticalScrollBarPolicy ( ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS );
add(sp2);
lbl4 = new JLabel();
lbl4.setSize(420,40);
lbl4.setLocation(570,10);
lbl4.setEnabled(false);
lbl4.setFont(new Font ("arial",5,17));
lbl4.setText("Data Display");
add(lbl4);
textArea = new JTextArea(55, 50);
textArea.setEditable(false);
textArea.setSize(800,640);
textArea.setLocation(560,60);
textArea.setFont(new Font("arial",5,19));
textArea.setDisabledTextColor(Color.black);
sp = new JScrollPane(textArea);
sp.setVerticalScrollBarPolicy ( ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS );
add(sp);
setVisible(true);
}
# 1 楼答案
谢谢你们的帮助,我找到了答案。正如@matt告诉我的,我应该将大小和位置添加到JScrollPane而不是textArea。所以我做了,现在对我来说很有效
代码如下
# 2 楼答案
我认为这应该解决你的问题
您会注意到,我删除了
addActionListener()
方法之间的this
,因为您必须指定ActionListener
要做什么StartingPoint
(主)类:GUI_CWK
类:# 3 楼答案
下面是使用滚动窗格的示例
主要区别在于我设置了内容窗格,以便了解其布局管理器。您似乎在手动设置所有尺寸,我很惊讶它能正常工作。你应该选择一个好的布局管理器pick one你想做什么就做什么
还要注意,这是一个将编译的最小示例