用户将输入一个介于1和99之间的数字。我编写的代码最多，我无法弄清楚是否可以使用计算按钮进行计算。我可以真正使用一些一步一步的帮助我愿意学习，如果有人可以帮助我。我是一个非常初学者。
package minimumchris;
import javax.swing.JButton;
import javax.swing.JTextField;
public class useri extends javax.swing.JFrame {
public useri() {
initComponents();
}
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jScrollPane1 = new javax.swing.JScrollPane();
jLabel1 = new javax.swing.JLabel();
jTextField1 = new javax.swing.JTextField();
jLabel2 = new javax.swing.JLabel();
jLabel3 = new javax.swing.JLabel();
jLabel4 = new javax.swing.JLabel();
jLabel5 = new javax.swing.JLabel();
jButton1 = new javax.swing.JButton();
jButton2 = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jLabel1.setText("enter a number between 1-99");
jLabel2.setText("quarters");
jLabel3.setText("dimes");
jLabel4.setText("nickels");
jLabel5.setText("pennies");
jButton1.setText("calculate");
jButton1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton1ActionPerformed(evt);
}
});
jButton2.setText("clear");
org.jdesktop.layout.GroupLayout layout = new org.jdesktop.layout.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(layout.createSequentialGroup()
.add(layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(layout.createSequentialGroup()
.addContainerGap()
.add(jLabel1, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, 197, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(org.jdesktop.layout.LayoutStyle.RELATED, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.add(jTextField1, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, 47, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE))
.add(layout.createSequentialGroup()
.add(66, 66, 66)
.add(layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(jLabel5)
.add(jLabel4)
.add(jLabel3)
.add(jLabel2))
.add(0, 0, Short.MAX_VALUE)))
.addContainerGap())
.add(layout.createSequentialGroup()
.addContainerGap()
.add(jButton1, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, 195, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(org.jdesktop.layout.LayoutStyle.RELATED)
.add(jButton2, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, 177, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE)
.addContainerGap(16, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(layout.createSequentialGroup()
.addContainerGap()
.add(layout.createParallelGroup(org.jdesktop.layout.GroupLayout.TRAILING)
.add(jTextField1, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE)
.add(jLabel1))
.add(32, 32, 32)
.add(jLabel2)
.add(18, 18, 18)
.add(jLabel3)
.addPreferredGap(org.jdesktop.layout.LayoutStyle.UNRELATED)
.add(jLabel4)
.addPreferredGap(org.jdesktop.layout.LayoutStyle.RELATED)
.add(jLabel5)
.add(29, 29, 29)
.add(layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING, false)
.add(jButton2, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, 73, Short.MAX_VALUE)
.add(jButton1, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
.addContainerGap(32, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
int cntrquart = 0;
int cntrdimes = 0;
int cntrpennies = 0;
int cntrnickels = 0;
JTextField jTextField=new JTextField(); // initialize textFild
JButton calculate =jButton1;
int quarters = Integer.parseInt(jTextField.getText());
while (quarters >= 25)
{
quarters = quarters - 25;
cntrquart++;
}
//dimes
int dimes = quarters;
while (dimes >= 10)
{
dimes = dimes - 10;
cntrdimes++;
}
//nickels
int nickels = dimes;
while (nickels >= 5)
{
nickels = nickels - 5;
cntrnickels++;
}
//pennies
int pennies = nickels;
while (pennies >= 1)
{
pennies = pennies - 1;
cntrpennies++;
}
jLabel2.setText("Quarter" + cntrquart );
jLabel3.setText("Dimes:" + cntrdimes );
jLabel4.setText("Nickels:" + cntrnickels );
jLabel5.setText("Pennies:" + cntrpennies );
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<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(useri.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(useri.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(useri.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(useri.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new useri().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton2;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JLabel jLabel3;
private javax.swing.JLabel jLabel4;
private javax.swing.JLabel jLabel5;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JTextField jTextField1;
// End of variables declaration
}
答案 0 :(得分：1)
问题是当你按下“计算”时你正在使用一个全新的JTextField：
JTextField jTextField=new JTextField(); // useless
JButton calculate =jButton1; // useless
int quarters = Integer.parseInt(jTextField.getText()); // should use jTextField1 (probably)
答案 1 :(得分：0)
像RC一样说道：
JTextField jTextField=new JTextField();
您正在创建一个不想要的新JTextField对象。由于您拥有的变量是类实例，因此您可以直接引用它们：
int quaters = Integer.parseInt(jTextField1.getText());
创建新变量意味着该变量的全新不同参数集和特定于实例的数据（如JTextField框内的内容）不共享。由于您（可能）用文本填充JTextField jTextField1，因此只能通过getText()对象本身调用jTextField1来检索文本。
除了这一点，我可以建议使用更直观的变量名称，只复制代码的相关部分。这有助于我们更快地找到您的问题。还请根据问题本身提出问题标题，“我需要帮助”不会让你到任何地方。
最后一点，如果用简单的除法/模式操作替换循环，可以进一步优化和简化代码。而不是：
while (quarters >= 25){
quarters = quarters - 25;
cntrquart++;
}
int dimes = quarters;
//...
做的：
cntrlquart = quarters / 25; //Integer division
int dimes = quarters % 25; //Mod operation, remainder of dividing by 25.