我正在Netbeans 7.1中构建一个GUI，它代表了医院设备项目的输液泵。按jButton1应显示某个jLabel，表示输液正在运行。再次按jButton1应该停止它。我唯一的问题是按钮需要在第一次工作之前点击两次。在那之后，它完全符合我希望它的工作方式。我在这个问题上搜索了多个线程，但其他解决方案似乎不起作用。谁能帮我？提前谢谢！
package infusion;
public class Infusion {
static Interface screen;
public Infusion(){
screen = new Interface();
screen.setVisible(true);
screen.jLabel3.setVisible(true);
screen.jButton1.setVisible(true);
}
public static void main(String[] args) {
// TODO code application logic here
Infusion infusion = new Infusion();
}
}
这是用户界面的代码（主要由Netbeans生成）。 jButton1ActionPerformed的实现是我改编的唯一代码。
package infusion;
public class Interface extends javax.swing.JFrame {
boolean pump1Running = false;
/**
* Creates new form Interface
*/
public Interface() {
initComponents();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jPanel1 = new javax.swing.JPanel();
jLabel3 = new javax.swing.JLabel();
jSeparator1 = new javax.swing.JSeparator();
jButton1 = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setBackground(new java.awt.Color(255, 255, 255));
setPreferredSize(new java.awt.Dimension(800, 562));
setResizable(false);
jPanel1.setPreferredSize(new java.awt.Dimension(800, 540));
javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout.setHorizontalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 800, Short.MAX_VALUE)
);
jPanel1Layout.setVerticalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 540, Short.MAX_VALUE)
);
jLabel3.setIcon(new javax.swing.ImageIcon(getClass().getResource("/Pauze.png"))); // NOI18N
jLabel3.setText("Infusion Paused");
jButton1.setText("Start infusion");
jButton1.setCursor(new java.awt.Cursor(java.awt.Cursor.HAND_CURSOR));
jButton1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton1ActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addContainerGap(36, Short.MAX_VALUE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addComponent(jButton1)
.addGap(18, 18, 18)
.addComponent(jLabel3, javax.swing.GroupLayout.PREFERRED_SIZE, 189, javax.swing.GroupLayout.PREFERRED_SIZE))
.addComponent(jSeparator1, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.PREFERRED_SIZE, 649, javax.swing.GroupLayout.PREFERRED_SIZE))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap())
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addGap(0, 22, Short.MAX_VALUE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(51, 51, 51)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jButton1, javax.swing.GroupLayout.PREFERRED_SIZE, 64, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(jLabel3, javax.swing.GroupLayout.PREFERRED_SIZE, 59, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18, 18, 18)
.addComponent(jSeparator1, javax.swing.GroupLayout.PREFERRED_SIZE, 10, javax.swing.GroupLayout.PREFERRED_SIZE))
.addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)))
);
pack();
}// </editor-fold>
//Booleans
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
if (pump1Running == false){
jLabel3.setIcon(new javax.swing.ImageIcon(getClass().getResource("/Pauze.png")));
jLabel3.setText("Infusion Paused");
jButton1.setText("Start Infusion");
pump1Running = true;
}
else {//if (pump1Running == true){
jLabel3.setIcon(new javax.swing.ImageIcon(getClass().getResource("/arrows64.gif")));
jLabel3.setText("Running infusion");
jButton1.setText("Stop Infusion");
pump1Running = false;
}
// TODO add your handling code here:
}
/**
* @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(Interface.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(Interface.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(Interface.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(Interface.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/*
* Create and display the form
*/
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new Interface().setVisible(true);
}
});
}
// Variables declaration - do not modify
public static javax.swing.JButton jButton1;
public javax.swing.JLabel jLabel3;
public javax.swing.JPanel jPanel1;
private javax.swing.JSeparator jSeparator1;
// End of variables declaration
}
答案 0 :(得分：5)
问题：pump1Running = false，因此当您单击按钮时，它会将标签和图像设置为与之相同的内容。然后它将其切换为true，然后它可以切换到另一个标签/图像。
if (pump1Running){
jLabel3.setIcon(new ImageIcon(getClass().getResource("/Pauze.png")));
jLabel3.setText("Infusion Paused");
jButton1.setText("Start Infusion");
pump1Running = !pump1Running;
}
else {//if (pump1Running == true){
jLabel3.setIcon(new ImageIcon(getClass().getResource("/Pauze.png")));
jLabel3.setText("Running infusion");
jButton1.setText("Stop Infusion");
pump1Running = !pump1Running;
}
这会切换pump1Running来回运行并解决问题。