calcdouble.java

用Netbean编写的图形用户界面设计实验 包括绘制正弦曲线和市属四则运算器

/*
 * CalcDouble.java
 *
 * Created on 2008年11月18日, 下午2:17
 */
package problem_2;

import javax.swing.JOptionPane;

/**
 *
 * @author  xiao lei
 */
public class CalcDouble extends javax.swing.JFrame {

    /** Creates new form CalcDouble */
    public CalcDouble() {
        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">//GEN-BEGIN:initComponents
    private void initComponents() {

        jLabel2 = new javax.swing.JLabel();
        jLabel1 = new javax.swing.JLabel();
        tfFirst = new javax.swing.JTextField();
        jLabel3 = new javax.swing.JLabel();
        tfSecond = new javax.swing.JTextField();
        jLabel4 = new javax.swing.JLabel();
        cboOper = new javax.swing.JComboBox();
        jLabel5 = new javax.swing.JLabel();
        tfResult = new javax.swing.JTextField();
        btnCompute = new javax.swing.JButton();
        btnQuit = new javax.swing.JButton();

        jLabel2.setText("jLabel2");

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("实数四则运算器");

        jLabel1.setText("第一个实数");

        jLabel3.setText("第二个实数");

        jLabel4.setText("运算符");

        cboOper.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "+", "-", "*", "/" }));

        jLabel5.setText("运算结果");

        tfResult.setEditable(false);

        btnCompute.setText("计算");
        btnCompute.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnComputeActionPerformed(evt);
            }
        });

        btnQuit.setText("退出");

        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)
                    .addGroup(layout.createSequentialGroup()
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(jLabel1)
                            .addComponent(jLabel3)
                            .addComponent(jLabel4))
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(tfSecond, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, 299, Short.MAX_VALUE)
                            .addComponent(tfFirst, javax.swing.GroupLayout.DEFAULT_SIZE, 299, Short.MAX_VALUE)
                            .addComponent(cboOper, 0, 299, Short.MAX_VALUE)))
                    .addGroup(layout.createSequentialGroup()
                        .addComponent(jLabel5)
                        .addGap(18, 18, 18)
                        .addComponent(tfResult, javax.swing.GroupLayout.DEFAULT_SIZE, 300, Short.MAX_VALUE))
                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                        .addComponent(btnCompute)
                        .addGap(15, 15, 15)
                        .addComponent(btnQuit)))
                .addContainerGap())
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel1)
                    .addComponent(tfFirst, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel3)
                    .addComponent(tfSecond, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel4)
                    .addComponent(cboOper, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel5)
                    .addComponent(tfResult, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(btnCompute)
                    .addComponent(btnQuit))
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );

        java.awt.Dimension screenSize = java.awt.Toolkit.getDefaultToolkit().getScreenSize();
        setBounds((screenSize.width-408)/2, (screenSize.height-255)/2, 408, 255);
    }// </editor-fold>//GEN-END:initComponents

private void btnComputeActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnComputeActionPerformed
// TODO add your handling code here:
    if ("".equals(tfFirst.getText()) || "".equals(tfSecond.getText())) {
        JOptionPane.showMessageDialog(null, "请完整填写2个实数");
    } else {
        try {
            double d1 = Double.parseDouble(tfFirst.getText());
            double d2 = Double.parseDouble(tfSecond.getText());
            double result = 0;
            if ("+".equals(cboOper.getSelectedItem())) {
                result = d1 + d2;
            }
            if ("-".equals(cboOper.getSelectedItem())) {
                result = d1 - d2;
            }
            if ("*".equals(cboOper.getSelectedItem())) {
                result = d1 * d2;
            }
            if ("/".equals(cboOper.getSelectedItem())) {
                result = d1 / d2;
            }
            tfResult.setText("" + result);
        } catch (Exception ex) {
            JOptionPane.showMessageDialog(null, "输入的实数有错误.");
        }
    }
}//GEN-LAST:event_btnComputeActionPerformed

    /**
    * @param args the command line arguments
    */
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new CalcDouble().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify//GEN-BEGIN:variables
    private javax.swing.JButton btnCompute;
    private javax.swing.JButton btnQuit;
    private javax.swing.JComboBox cboOper;
    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.JTextField tfFirst;
    private javax.swing.JTextField tfResult;
    private javax.swing.JTextField tfSecond;
    // End of variables declaration//GEN-END:variables

}