java以适当的方式更新jLabel和jTextField
我发现了几个关于这个问题的问题,花了一个小时在上面,但我自己仍然不能解决我的问题。我想做的只是打开一个表单并使用setText()更改jLabel1和jTextField1的值
梅因。爪哇:
package defaultpackage;
public class Main {
public void main(String args[]) {
new InfoWindow().setVisible(true);
InfoWindow.Refresh("a", "b");
}
}
信息窗口。爪哇:
package defaultpackage;
public class InfoWindow extends javax.swing.JFrame {
public static void Refresh(String label, String textfield) {
jLabel1.setText(label);
jTextField1.setText(textfield);
}
public InfoWindow() {
initComponents();
}
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jLabel1 = new javax.swing.JLabel();
jTextField1 = new javax.swing.JTextField();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jLabel1.setText("jLabel1");
jTextField1.setText("jTextField1");
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(jTextField1, javax.swing.GroupLayout.DEFAULT_SIZE, 179, Short.MAX_VALUE)
.addComponent(jLabel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addComponent(jLabel1)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
public static void main(String args[]) {
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/*
* If Nimbus (introduced in Java SE 6) is not available, stay with the
* default look and feel. For details see
* http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(InfoWindow.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(InfoWindow.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(InfoWindow.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(InfoWindow.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new InfoWindow().setVisible(true);
}
});
}
// Variables declaration - do not modify
public static javax.swing.JLabel jLabel1;
public static javax.swing.JTextField jTextField1;
// End of variables declaration
}
窗口中的值不会更新。我错过了什么
# 1 楼答案
类
Main
中的main
-方法缺少static
关键字,因此无法运行此关键字我假设您确实运行了
InfoWindow
的main
方法,它不调用Refresh
还有几点:
JLabel
,JTextField
)不应声明为static
。您不能在窗口的实例之间共享它们这将迫使您使
Refresh
也成为非静态的refresh
而不是Refresh
)开头这就是
Main
-类的外观:# 2 楼答案
InfoWindow
的实例上调用了名称不正确的Refresh
方法我建议您将
Refresh
作为一个非静态方法,并遵循Java命名约定。还可以通过SwingUtilities.invokeLater
在EDT中创建和修改组件