给大家演示个简单的java计算器

    在开始java的旅途时，别人提议做一个简单的计算器。经过一段时间的积累，我终于在全方位的资料中完成了。当时感觉是很兴奋。能做点东西了！~ 呵呵 以下是部分截图以及代码。

    import java.awt.BorderLayout;
    import java.awt.Color;
    import java.awt.FlowLayout;
    import java.awt.GridLayout;
    import java.awt.event.ActionEvent;
    import java.awt.event.ActionListener;

    import javax.swing.JButton;
    import javax.swing.JFrame;
    import javax.swing.JMenu;
    import javax.swing.JMenuBar;
    import javax.swing.JMenuItem;
    import javax.swing.JOptionPane;
    import javax.swing.JPanel;
    import javax.swing.JTextField;

    public class JSanQi implements ActionListener ...{
        JFrame f1;

        JPanel p1, p2, p3;

        JTextField t1;

        JButton bt[];

        JButton bdoc, bexit, back, bzero, badd, bsub, bmul, bdiv, bcanl, bequl;

        boolean Key;

        JMenuBar menu;

        JMenu m1;

        JMenuItem mt1, mt2;

        Double fnum;

        int key, doc;

        @SuppressWarnings("deprecation")
        public JSanQi() ...{
            fnum = 0.0;
            Key = true;
            doc = 0;
            f1 = new JFrame("My Calculator!");
            f1.setLayout(new BorderLayout());
            p1 = new JPanel();
            p2 = new JPanel();
            p3 = new JPanel();
            t1 = new JTextField();
            menu = new JMenuBar();
            m1 = new JMenu("file");
            mt1 = new JMenuItem("nihao!");
            mt2 = new JMenuItem("exit!");
            t1.setEditable(false);
            t1.setBackground(new Color(205,201,120));
            f1.add(p2, BorderLayout.NORTH);
            f1.add(p1);
            p2.setLayout(new FlowLayout());
            p2.add(menu, FlowLayout.LEFT);
            menu.add(m1);
            m1.add(mt1);
            m1.add(mt2);
            mt1.addActionListener(this);
            mt2.addActionListener(this);
            p1.setLayout(new BorderLayout());
            p1.add(t1, BorderLayout.NORTH);
            p1.add(p3);
            bt = new JButton[10];
            for (int i = 0; i < 10; i++) ...{
                bt[i] = new JButton(Integer.toString(i));
            }
            bdoc = new JButton(".");
            bexit = new JButton("Exit!");
            back = new JButton("Back!");
            back.setForeground(new Color(255, 0, 0));
            bexit.setForeground(new Color(0, 0, 255));
            bexit.setBackground(new Color(120,120,225));
            bzero = new JButton("00");
            badd = new JButton("+");
            bsub = new JButton("-");
            bmul = new JButton("*");
            bdiv = new JButton("/");
            bcanl = new JButton("EC");
            bequl = new JButton("=");
            //bequl.setLabel("123");
            //bequl.addNotify();
            p3.setLayout(new GridLayout(4, 5));

            p3.add(bt[1]);
            p3.add(bt[2]);
            p3.add(bt[3]);
            p3.add(badd);
            p3.add(bsub);
            p3.add(bt[4]);

            p3.add(bt[5]);
            p3.add(bt[6]);
            p3.add(bmul);
            p3.add(bdiv);
            p3.add(bt[7]);
            p3.add(bt[8]);
            p3.add(bt[9]);
            p3.add(back);
            p3.add(bequl);
            p3.add(bt[0]);
            p3.add(bzero);
            p3.add(bdoc);
            p3.add(bcanl);
            p3.add(bexit);

            bt[0].addActionListener(this);
            bt[1].addActionListener(this);
            bt[2].addActionListener(this);
            bt[3].addActionListener(this);
            bt[4].addActionListener(this);
            bt[5].addActionListener(this);
            bt[6].addActionListener(this);
            bt[7].addActionListener(this);
            bt[8].addActionListener(this);
            bt[9].addActionListener(this);

            bdoc.addActionListener(this);
            bexit.addActionListener(this);
            back.addActionListener(this);
            bzero.addActionListener(this);
            badd.addActionListener(this);
            bsub.addActionListener(this);
            bmul.addActionListener(this);
            bdiv.addActionListener(this);
            bcanl.addActionListener(this);
            bequl.addActionListener(this);

            f1.setSize(290, 220);
            f1.pack();
            f1.setVisible(true);
        }

        public static void main(String[] args) ...{
            new JSanQi();

        }

        public void actionPerformed(ActionEvent event) ...{
            Object temp = event.getSource();

            try ...{
                for (int i = 0; i < 10; i++) ...{
                    if (temp == bt[i] && Key == true) ...{
                        t1.setText(t1.getText() + Integer.toString(i));
                    }
                }
                if (temp == badd || temp == bsub || temp == bmul || temp == bdiv) ...{
                    if (temp == badd && Key == true) ...{
                        key = 1;
                        fnum = Double.parseDouble(t1.getText());
                        // t1.setText(t1.getText()+fnum);
                    }
                    if (temp == bsub && Key == true) ...{
                        key = 2;
                        fnum = Double.parseDouble(t1.getText());
                    }
                    if (temp == bmul && Key == true) ...{
                        key = 3;
                        fnum = Double.parseDouble(t1.getText());
                    }
                    if (temp == bdiv && Key == true) ...{
                        if (Double.parseDouble(t1.getText()) == 0) ...{
                            t1.setText("Wrong action!");
                        } else ...{
                            key = 4;
                            fnum = Double.parseDouble(t1.getText());
                        }
                    }
                    t1.setText("");
                    doc=0;
                }
                if (temp == bequl && Key == true) ...{
                    switch (key) ...{
                    case 1:
                        fnum += Double.parseDouble(t1.getText());
                        t1.setText(Double.toString(fnum));
                        break;
                    case 2:
                        fnum -= Double.parseDouble(t1.getText());
                        t1.setText(Double.toString(fnum));
                        break;
                    case 3:
                        fnum *= Double.parseDouble(t1.getText());
                        t1.setText(Double.toString(fnum));
                        break;
                    case 4:
                        fnum /= Double.parseDouble(t1.getText());
                        t1.setText(Double.toString(fnum));
                        break;
                    default:
                        break;
                    }
                    doc=0;
                }
                if (temp == bcanl) ...{
                    t1.setText("");
                    Key = true;
                    doc=0;

                }
                if (temp == bexit || temp == mt2) ...{
                    System.exit(0);
                }
                if (temp == bzero && Key==true) ...{
                    t1.setText(t1.getText() + "00");
                    //doc=0;
                }
                if (temp == mt1) ...{
                    JOptionPane.showMessageDialog(p1, "How Are You! "
                            + "Architect Is Topwise ^_^");

                }

                if (temp == bdoc && Key==true) ...{
                    if (doc == 0) ...{
                        t1.setText(t1.getText() + ".");
                        }

                    if(doc==1) ...{
                        t1.setText("Wrong Action");
                        Key = false;
                        doc = 0;
                    }
                    doc = 1;
                }
                if (temp==back && Key==true)...{

                }

            } catch (Exception e) ...{
                t1.setText("Wrong Action!");
                Key = false;
            }
        }

    }
   

【责编:Ken】