jsq.java~2~

用java语言实现的简单计算器

package jsq;



import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.JButton;
import javax.swing.JTextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;


public class jsq extends JApplet{


                boolean flag = false;

                String operand1;

                String operand2;

                double result;

                String action;

                JPanel contentPane;
                JButton btn0 = new JButton();
                JButton btn1 = new JButton();
                JButton btn2 = new JButton();
                JButton btn3 = new JButton();
                JButton btn4 = new JButton();
                JButton btn5 = new JButton();
                JButton btn6 = new JButton();
                JButton btn7 = new JButton();
                JButton btn8 = new JButton();
                JButton btn9 = new JButton();

                JButton btnClear = new JButton();        //清除按钮
                JButton btnEqual = new JButton();        //等于按钮
                JButton btnPlus = new JButton();         //加按钮
                JButton btnMinus = new JButton();        //减按钮
                JButton btnMultiply = new JButton();     //乘按钮
                JButton btnDivide = new JButton();       //除按钮


            JTextField txtResult = new JTextField();       //计算结果

        public void init(){


                contentPane=(JPanel)getContentPane();
                contentPane.setLayout(null);
                setSize(300,300);

                //显示结果
                txtResult.setFont(new java.awt.Font("Tahoma", Font.PLAIN, 13));
        txtResult.setText("");
        txtResult.setHorizontalAlignment(JTextField.RIGHT);
        txtResult.setBounds(new Rectangle(70, 50, 185, 28));

                btn0.setBounds(new Rectangle(65, 280, 45, 45));
        btn0.setFont(new java.awt.Font("Tahoma", Font.PLAIN, 13));
                btn0.addActionListener(new btn0(this));
                btn0.setText("0");

                //清除按钮
                btnClear.setBounds(new Rectangle(115,280,45,45));
                btnClear.setFont(new java.awt.Font("Tahoma",Font.PLAIN,13));
                btnClear.setText("C");
                btnClear.addActionListener(new btnClear(this));

                //等于按钮
                btnEqual.setBounds(new Rectangle(165,280,45,45));
                btnEqual.setFont(new java.awt.Font("Tahoma",Font.PLAIN,13));
                btnEqual.setText("=");
                btnEqual.addActionListener(new btnEqual(this));


                btn1.setBounds(new Rectangle(65, 220, 45, 45));
        btn1.setFont(new java.awt.Font("Tahoma", Font.PLAIN, 13));
        btn1.setText("1");
        btn1.addActionListener(new btn1(this));

        btn2.setBounds(new Rectangle(115, 220, 45, 45));
        btn2.setFont(new java.awt.Font("Tahoma", Font.PLAIN, 13));
        btn2.setText("2");
        btn2.addActionListener(new btn2(this));

        btn3.setBounds(new Rectangle(165, 220, 45, 45));
        btn3.setFont(new java.awt.Font("Tahoma", Font.PLAIN, 13));
        btn3.setText("3");
        btn3.addActionListener(new btn3(this));

        btn4.setBounds(new Rectangle(65, 160, 45, 45));
        btn4.setFont(new java.awt.Font("Tahoma", Font.PLAIN, 13));
        btn4.setText("4");
        btn4.addActionListener(new btn4(this));

        btn5.setBounds(new Rectangle(115, 160, 45, 45));
        btn5.setFont(new java.awt.Font("Tahoma", Font.PLAIN, 13));
        btn5.setText("5");
        btn5.addActionListener(new btn5(this));

                btn6.setBounds(new Rectangle(165,160,45,45));
                btn6.setFont(new java.awt.Font("Tahoma",Font.PLAIN,13));
                btn6.setText("6");
                btn6.addActionListener(new btn6(this));

                btn7.setBounds(new Rectangle(65,100,45,45));
                btn7.setFont(new java.awt.Font("Tahoma",Font.PLAIN,13));
                btn7.setText("7");
                btn7.addActionListener(new btn7(this));

                btn8.setBounds(new Rectangle(115,100,45,45));
                btn8.setFont(new java.awt.Font("Tahoma",Font.PLAIN,13));
                btn8.setText("8");
                btn8.addActionListener(new btn8(this));

                btn9.setBounds(new Rectangle(165,100,45,45));
                btn9.setFont(new java.awt.Font("Tahoma",Font.PLAIN,13));
                btn9.setText("9");
                btn9.addActionListener(new btn9(this));

                //加
                btnPlus.setBounds(new Rectangle(215,280,45,45));
                btnPlus.setFont(new java.awt.Font("Tahoma",Font.PLAIN,13));
                btnPlus.setText("+");
                btnPlus.addActionListener(new btnPlus(this));

                //减
                btnMinus.setBounds(new Rectangle(215,220,45,45));
                btnMinus.setFont(new java.awt.Font("Tahoma",Font.PLAIN,13));
                btnMinus.setText("-");
                btnMinus.addActionListener(new btnMinus(this));

                //乘
                btnMultiply.setBounds(new Rectangle(215,160,45,45));
                btnMultiply.setFont(new java.awt.Font("Tahoma",Font.PLAIN,13));
                btnMultiply.setText("*");
                btnMultiply.addActionListener(new btnMultiply(this));

                //除
                btnDivide.setBounds(new Rectangle(215,100,45,45));
                btnDivide.setFont(new java.awt.Font("Tahoma",Font.PLAIN,13));
                btnDivide.setText("/");
                btnDivide.addActionListener(new btnDivide(this));


                contentPane.add(txtResult,null);
                contentPane.add(btn0,null);
                contentPane.add(btn1,null);
                contentPane.add(btn2,null);
                contentPane.add(btn3,null);
                contentPane.add(btn4,null);
                contentPane.add(btn5,null);
                contentPane.add(btn6,null);
                contentPane.add(btn7,null);
                contentPane.add(btn8,null);
                contentPane.add(btn9,null);
                contentPane.add(btnClear,null);
                contentPane.add(btnEqual,null);
                contentPane.add(btnPlus,null);
                contentPane.add(btnMinus,null);
                contentPane.add(btnMultiply,null);
                contentPane.add(btnDivide,null);
        }


        //0的事件监听器
        public void btn0_actionPerformed(ActionEvent e){

                if(flag){

                        txtResult.setText(btn0.getActionCommand());

                        flag = false;
                }
                else{
                        txtResult.setText(txtResult.getText()+btn0.getActionCommand());
                }
        }

        class btn0 implements ActionListener{

                private jsq adaptee;

                btn0(jsq adaptee){

                        this.adaptee=adaptee;
                }

                public void actionPerformed(ActionEvent e){

                        adaptee.btn0_actionPerformed(e);
                }
        }



        //1的事件监听器
        public void btn1_actionPerformed(ActionEvent e){
                if (flag) {
            txtResult.setText(btn1.getActionCommand());
            flag = false;
        }
        else {
            txtResult.setText(txtResult.getText() + btn1.getActionCommand());
        }


        }

        class btn1 implements ActionListener{

                private jsq adaptee;

                btn1(jsq adaptee){

                        this.adaptee=adaptee;
                }

                public void actionPerformed(ActionEvent e){

                        adaptee.btn1_actionPerformed(e);
                }
        }


        //2的事件监听器
        public void btn2_actionPerformed(ActionEvent e){
                if (flag) {
            txtResult.setText(btn2.getActionCommand());
            flag = false;
        }
        else {
            txtResult.setText(txtResult.getText() + btn2.getActionCommand());
        }
        }

        class btn2 implements ActionListener{

                private jsq adaptee;

                btn2(jsq adaptee){

                        this.adaptee=adaptee;
                }

                public void actionPerformed(ActionEvent e){

                        adaptee.btn2_actionPerformed(e);
                }
        }


        //3的事件监听器
        public void btn3_actionPerformed(ActionEvent e){
                if (flag) {
            txtResult.setText(btn3.getActionCommand());
            flag = false;
        }
        else {
            txtResult.setText(txtResult.getText() + btn3.getActionCommand());
        }
        }

        class btn3 implements ActionListener{

                private jsq adaptee;

                btn3(jsq adaptee){

                        this.adaptee=adaptee;
                }

                public void actionPerformed(ActionEvent e){

                        adaptee.btn3_actionPerformed(e);
                }
        }


        //4的事件监听器
        public void btn4_actionPerformed(ActionEvent e){
                if (flag) {
            txtResult.setText(btn4.getActionCommand());
            flag = false;
        }
        else {
            txtResult.setText(txtResult.getText() + btn4.getActionCommand());
        }


        }

        class btn4 implements ActionListener{

                private jsq adaptee;

                btn4(jsq adaptee){

                        this.adaptee=adaptee;
                }

                public void actionPerformed(ActionEvent e){

                        adaptee.btn4_actionPerformed(e);
                }