Java 使用netbeans制作简单的计算器
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时间：2020-08-12 10:56:53 来源:igfitidea点击:
making simple Calculator using netbeans
提问by
i am making a simple calculator using Net beans but there is a problem in between Button and text field . i want that thing where i click button "1" after clicking one it supposed to show one but nothing showing and please help how to setup "+" button in between them help please. /* * To change this template, choose Tools | Templates * and open the template in the editor. */
我正在使用 Net beans 制作一个简单的计算器，但在 Button 和文本字段之间存在问题。我想要那个我点击按钮“1”后点击它应该显示一个但没有显示的东西，请帮助如何在它们之间设置“+”按钮帮助。/* * 要更改此模板，请选择工具 | 模板 * 并在编辑器中打开模板。*/
/**
*
* @author Administrator
*/
public class Calculator extends javax.swing.JFrame {
/**
* Creates new form Calculator
*/
public Calculator() {
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();
jButton12 = new javax.swing.JButton();
jButton10 = new javax.swing.JButton();
jButton11 = new javax.swing.JButton();
jButton9 = new javax.swing.JButton();
jButton1 = new javax.swing.JButton();
jTextField1 = new javax.swing.JTextField();
jButton8 = new javax.swing.JButton();
jButton5 = new javax.swing.JButton();
jButton4 = new javax.swing.JButton();
jButton2 = new javax.swing.JButton();
jButton7 = new javax.swing.JButton();
jButton6 = new javax.swing.JButton();
jButton13 = new javax.swing.JButton();
jButton3 = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jPanel1.setBorder(javax.swing.BorderFactory.createTitledBorder(null, "Rajendra Calculator", javax.swing.border.TitledBorder.CENTER, javax.swing.border.TitledBorder.ABOVE_TOP));
jButton12.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton12.setText("=");
jButton10.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton10.setText("0");
jButton11.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton11.setText("+");
jButton11.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton11ActionPerformed(evt);
}
});
jButton9.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton9.setText("9");
jButton1.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton1.setText("1");
jButton1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton1ActionPerformed(evt);
}
});
jTextField1.setHorizontalAlignment(javax.swing.JTextField.RIGHT);
jTextField1.setText("0");
jTextField1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jTextField1ActionPerformed(evt);
}
});
jButton8.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton8.setText("8");
jButton5.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton5.setText("5");
jButton4.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton4.setText("4");
jButton4.setToolTipText("");
jButton4.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton4ActionPerformed(evt);
}
});
jButton2.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton2.setText("2");
jButton2.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton2ActionPerformed(evt);
}
});
jButton7.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton7.setText("7");
jButton6.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton6.setText("6");
jButton13.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton13.setText("Clear");
jButton3.setFont(new java.awt.Font("Arial Black", 0, 11)); // NOI18N
jButton3.setText("3");
javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout.setHorizontalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel1Layout.createSequentialGroup()
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addGroup(jPanel1Layout.createSequentialGroup()
.addComponent(jButton4)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(jButton5)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(jButton6))
.addComponent(jTextField1)
.addGroup(jPanel1Layout.createSequentialGroup()
.addComponent(jButton1)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(jButton2)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(jButton3))
.addGroup(jPanel1Layout.createSequentialGroup()
.addComponent(jButton7)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(jButton8)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(jButton9)))
.addGroup(jPanel1Layout.createSequentialGroup()
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(jButton11, javax.swing.GroupLayout.DEFAULT_SIZE, 65, Short.MAX_VALUE)
.addComponent(jButton10, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(jButton12, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(jButton13, javax.swing.GroupLayout.DEFAULT_SIZE, 66, Short.MAX_VALUE)))))
);
jPanel1Layout.setVerticalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel1Layout.createSequentialGroup()
.addContainerGap(25, Short.MAX_VALUE)
.addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, 42, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jButton1)
.addComponent(jButton2)
.addComponent(jButton3))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jButton4)
.addComponent(jButton5)
.addComponent(jButton6))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jButton7)
.addComponent(jButton8)
.addComponent(jButton9))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jButton10)
.addComponent(jButton13))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jButton11)
.addComponent(jButton12))
.addContainerGap())
);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(18, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addComponent(jPanel1, 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>
private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
jTextField1.setText(jTextField1.getText()+"1");
}
private void jTextField1ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
jTextField1.setText(jTextField1.getText()+"2"); // TODO add your handling code here:
}
private void jButton11ActionPerformed(java.awt.event.ActionEvent evt) {
int valA = Integer.parseInt(jTextField1.getText());
int valB = Integer.parseInt(jTextField1.getText()); // TODO add your handling code here:
int valC = valA+valB;
jTextField1.append(Integer.toString(valC));
jTextField1.append("\n"); // 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(Calculator.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(Calculator.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(Calculator.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(Calculator.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 Calculator().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton10;
private javax.swing.JButton jButton11;
private javax.swing.JButton jButton12;
private javax.swing.JButton jButton13;
private javax.swing.JButton jButton2;
private javax.swing.JButton jButton3;
private javax.swing.JButton jButton4;
private javax.swing.JButton jButton5;
private javax.swing.JButton jButton6;
private javax.swing.JButton jButton7;
private javax.swing.JButton jButton8;
private javax.swing.JButton jButton9;
private javax.swing.JPanel jPanel1;
private javax.swing.JTextField jTextField1;
// End of variables declaration
}
采纳答案by camickr
...How to set up JButton ..where i press it and it shows "1" on textField
...如何设置 JButton ..我按下它并在 textField 上显示“1”
Typically, in cases like this the text field would be non-editable so you can effectively "append" text to the text field by using:
通常，在这种情况下，文本字段将是不可编辑的，因此您可以使用以下方法有效地将文本“附加”到文本字段：
textField.replaceSelection("1");
However, the better approach is to share an Action for all the buttons:
但是，更好的方法是为所有按钮共享一个 Action：
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
public class ButtonCalculator extends JPanel
{
private JButton[] buttons;
private JTextField display;
public ButtonCalculator()
{
Action numberAction = new AbstractAction()
{
@Override
public void actionPerformed(ActionEvent e)
{
display.replaceSelection(e.getActionCommand());
}
};
display = new JTextField();
display.setEditable( false );
display.setHorizontalAlignment(JTextField.RIGHT);
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout( new GridLayout(0, 5) );
buttons = new JButton[10];
for (int i = 0; i < buttons.length; i++)
{
String text = String.valueOf(i);
JButton button = new JButton( text );
button.addActionListener( numberAction );
buttons[i] = button;
buttonPanel.add( button );
// Support Key Bindings
KeyStroke pressed = KeyStroke.getKeyStroke(text);
InputMap inputMap = button.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
inputMap.put(pressed, text);
button.getActionMap().put(text, numberAction);
}
setLayout( new BorderLayout() );
add(display, BorderLayout.NORTH);
add(buttonPanel, BorderLayout.SOUTH);
}
private static void createAndShowUI()
{
UIManager.put("Button.margin", new Insets(5, 10, 5, 10) );
JFrame frame = new JFrame("Button Calculator");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add( new ButtonCalculator() );
frame.setResizable( false );
frame.pack();
frame.setLocationByPlatform( true );
frame.setVisible( true );
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowUI();
}
});
}
}
回答by MadProgrammer
JTextFielddoes not have an appendmethod, it only has a setTextmethod.
JTextField没有append方法，只有setText方法。
If you really need "appending" capability, then you need to use a JTextAreainstead...
如果您确实需要“附加”功能，那么您需要JTextArea改用...
Take some time and read through Creating a GUI with Swingand Using text components.
Personally, I would throw out the form designer and get to know the API as well as you can, it will give a greater appreciation of what the form designer does and when it's appropriate to use it...IMHO
就我个人而言，我会抛弃表单设计器并尽可能地了解 API，它会更好地了解表单设计器的工作以及何时使用它......恕我直言
Updated
更新
Your basic flow is off. A user enters a value and press "+", you then try and add the value in the text field to itself and re-apply the value back to the text field...This means that it is unlikely that the user will actually ever be able to sum two values together.
您的基本流程已关闭。用户输入一个值并按“+”，然后您尝试将文本字段中的值添加到自身并将该值重新应用回文本字段......这意味着用户实际上不太可能能够将两个值相加。
Instead, you should be storing the value in the text field in some kind of Listeach time the user clicks the "+" button and clearing the text field for the next value. When they press the "=" button, you should simply iterate over this list and put the result into the textfield and clear the list...
相反，您应该在List每次用户单击“+”按钮并清除文本字段以获取下一个值时以某种方式将值存储在文本字段中。当他们按下“=”按钮时，您应该简单地遍历此列表并将结果放入文本字段并清除列表...
For example...
例如...
private List<Integer> values = new ArrayList<Integer>(25);
/*...*/
private void jButton11ActionPerformed(java.awt.event.ActionEvent evt) {
try {
int valA = Integer.parseInt(jTextField1.getText());
values.add(valA);
} catch (NumberFormatException exp) {
exp.printStackTrace();
}
jTextField1.setText("");
}
You haven't provided an actionPerformedmethod for the "=" button, but it's contents would look something like...
您还没有actionPerformed为“=”按钮提供方法，但它的内容看起来像......
int result = 0;
for (int value : values) {
result += value;
}
values.clear();
jTextField1.setText(Integer.toString(result));
