計算器java,計算器JAVA圖形界面

本文目錄一覽：

• 1、JAVA 編寫計算器 要代碼最簡單的
• 2、怎麼用JAVA編程編寫一個計算器？
• 3、編寫計算器java

JAVA 編寫計算器 要代碼最簡單的

學java的時候自己編的，很簡單，能夠連續輸入計算式後進行計算

import java.awt.BorderLayout;

import java.awt.Color;

import java.awt.FlowLayout;

import java.awt.Font;

import java.awt.GridLayout;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.text.NumberFormat;

import java.util.ArrayList;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JPanel;

import javax.swing.JTextField;

/**簡易計算器，能夠進行簡單的計算

*

* @see 2008.12.9

*/

public class CalculatorA

implements ActionListener{

private JFrame frame;

private JTextField field;

private JButton[] allButtons;

private JButton clearButton;

// private JButton backButton;

String result=””;//保存結果

StringBuilder sb = new StringBuilder();//保存要進行的計算式

int x = 0; //用來判斷上一次的事件類型

String str = “123+456-789*0.=/”;

ArrayListString arrayList = new ArrayListString();//保存計算式，通過方法進行運算

public CalculatorA(){

frame = new JFrame(“我的計算器v1.1”);

frame.setLocation(300,300);

field = new JTextField(25);

allButtons = new JButton[16];

for(int i=0;iallButtons.length;i++){

allButtons[i]= new JButton(str.substring(i,i+1));

}

clearButton = new JButton(“CLEAR”);

// backButton = new JButton(“——”);

init();

setFondAndColor();

addEventHander();

}

public void init(){

frame.setLayout(new BorderLayout());

JPanel northPanel = new JPanel();

JPanel centerPanel = new JPanel();

JPanel southPanel = new JPanel();

northPanel.setLayout(new FlowLayout());

centerPanel.setLayout(new GridLayout(4,4));

southPanel.setLayout(new FlowLayout());

northPanel.add(field);

for(int i=0;iallButtons.length;i++){

centerPanel.add(allButtons[i]);

}

southPanel.add(clearButton);

//southPanel.add(backButton);

frame.add(northPanel,BorderLayout.NORTH);

frame.add(centerPanel,BorderLayout.CENTER);

frame.add(southPanel,BorderLayout.SOUTH);

}

//設置輸入字體

public void setFondAndColor(){

field.setFont(new Font(“宋體”,Font.BOLD,24));

field.setBackground(new Color(100,200,200));

field.setForeground(Color.RED);

//設置字體從右起始

field.setHorizontalAlignment(JTextField.RIGHT);

}

public void showMi(){

frame.pack();

frame.setResizable(false);

frame.setVisible(true);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

}

public void addEventHander(){

for(int i=0;iallButtons.length;i++){

allButtons[i].addActionListener(this);

}

clearButton.addActionListener(this);

// backButton.addActionListener(this);

}

@Override

public void actionPerformed(ActionEvent e) {

String str = e.getActionCommand();//取得當前事件返回的值

if(“0123456789.”.indexOf(str)!=-1){

if(x == 0){ //當x為0時表示還沒有進行輸入

result=str;

sb.append(str);

field.setText(str);

x = 1;

}

else if(x == 1){

result = result +str;

sb.append(str);

field.setText(result);

x = 1;

}

else if(x == 2){

sb.delete(0,sb.length());

result = result+str;

sb.append(str);

field.setText(result);

x = 1;

}

else if(x == 3){

result = str;

sb.delete(0,sb.length());

arrayList.clear();

field.setText(str);

sb.append(str);

field.setText(str);

x = 1;

}

else if(x == 4){

result =””;

sb.delete(0,sb.length());

arrayList.clear();

result = str;

sb.append(str);

field.setText(str);

x = 1;

}

else{

result = result +str;

sb.append(str);

field.setText(result);

x = 1;

}

}

else if(“+*-/”.indexOf(str)!=-1){

if(x == 0){

field.setText(“”);

x = 2;

}

else if(x == 1){

result = result + str;

arrayList.add(sb.toString());

arrayList.add(str);

sb.append(str);

field.setText(result);

x = 2;

}

else if(x == 2){

x = 2;

}

else if(x == 3){

field.setText(result+str);

arrayList.add(result);

arrayList.add(str);

result = result+str;

x = 2;

}

else if(x == 4){

result =””;

sb.delete(0,sb.length());

arrayList.clear();

x = 2;

}

else{

field.setText(result+str);

arrayList.add(result);

arrayList.add(str);

result = result+str;

x = 2;

}

}

else if(“=”.equals(str)){

if(x == 0){

field.setText(“0”);

arrayList.clear();

result = “0”;

x = 3;

}

else if(x == 1){

try{

arrayList.add(sb.toString());

arrayList = getResult(arrayList);

result = arrayList.get(0);

field.setText(result);

arrayList.clear();

x = 3;

}catch(Exception e1){

field.setText(“數據格式異常”);

x = 0;

}

}

else if(x == 2){

field.setText(“數據格式錯誤…..”);

arrayList.clear();

x = 0;

}

else if(x == 3){

field.setText(result);

x = 3;

}

else if(x == 4){

result =””;

sb.delete(0,sb.length());

arrayList.clear();

x = 3;

}

else {

try{

arrayList.add(sb.toString());

arrayList = getResult(arrayList);

result = arrayList.get(0);

field.setText(result);

arrayList.clear();

x = 3;

}catch(Exception e1){

field.setText(“數據格式異常”);

x = 0;

}

}

}

else if(“CLEAR”.equals(str)){

arrayList.clear();

field.setText(“0”);

arrayList.add(“0”);

x = 4;

}

else{

if(result.length()1){

result = result.substring(0,result.length()-1);

if(sb.length()0){

sb.delete(sb.length()-1,sb.length());

}

else {

sb.delete(0,1);

}

field.setText(result);

x = 5;

}

else{

result = “”;

sb.delete(0,sb.length());

arrayList.clear();

field.setText(“0”);

x = 0;

}

}

}

public static ArrayListString getResult(ArrayListString list){

String res = null;

String[] s = {“/”,”*”,”-“,”+”};

int i=0;

if(list.size()1){

for(;is.length;){

if(s[i].equals(“/”)){

for(int j=0;jlist.size();j++){

if(list.get(j).equals(s[i])){

res = Double.toString(Double.parseDouble(list.get(j-1))/Double.parseDouble(list.get(j+1)));

//本地的數據格式

NumberFormat nf = NumberFormat.getInstance();

res = nf.format(Double.parseDouble(res));

res = getChange(res);

list.set(j-1,res);

list.remove(j);

list.remove(j);

getResult(list);

}

}

i++;

}

else if(s[i].equals(“*”)){

for(int j=0;jlist.size();j++){

if(list.get(j).equals(s[i])){

res = Double.toString(Double.parseDouble(list.get(j-1))*Double.parseDouble(list.get(j+1)));

NumberFormat nf = NumberFormat.getInstance();

res = nf.format(Double.parseDouble(res));

res = getChange(res);

list.set(j-1,res);

list.remove(j);

list.remove(j);

getResult(list);

}

}

i++;

}

else if(s[i].equals(“-“)){

for(int j=0;jlist.size();j++){

if(list.get(j).equals(s[i])){

res = Double.toString(Double.parseDouble(list.get(j-1))-Double.parseDouble(list.get(j+1)));

NumberFormat nf = NumberFormat.getNumberInstance();

res = nf.format(Double.parseDouble(res));

res = getChange(res);

list.set(j-1,res);

list.remove(j);

list.remove(j);

getResult(list);

}

}

i++;

}

else {

for(int j=0;jlist.size();j++){

if(list.get(j).equals(s[i])){

res = Double.toString(Double.parseDouble(list.get(j-1))+Double.parseDouble(list.get(j+1)));

NumberFormat nf = NumberFormat.getInstance();

res = nf.format(Double.parseDouble(res));

res = getChange(res);

list.set(j-1,res);

list.remove(j);

list.remove(j);

getResult(list);

}

}

i++;

}

}

}

return list;

}

//對數字字元串進行排除不必要符號

public static String getChange(String res){

String s_temp = “”;

char[] c = new char[res.length()];

for(int k=0;kc.length;k++){

c[k] = res.charAt(k);

}

for(int k=0;kc.length;k++){

if((c[k]= ‘0’ c[k]= ‘9’)|| c[k] == ‘.’){

s_temp += c[k];

}

}

return s_temp;

}

public static void main(String[] args){

new CalculatorA().showMi();

}

}

怎麼用JAVA編程編寫一個計算器？

打開IED：打開自己java編程的軟體，採用的是eclipse軟體。

建立java工程。

編寫類。

編寫類的詳細步驟

1.類的基本結構：

由於這裡用到了界面，所以要進行窗口界面的編程，按鈕事件的處理，和計算處理界面；

package MyCaculator;

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

public class MyCaculator extends JFrame {

private int add=1,sub=2,mul=3,div=4;

private int op=0;

boolean ifOp;

private String output=”0″;

private Button[] jba=new Button[]{new Button(“7”),new Button(“8”),

new Button(“9”),new Button(“+”),

new Button(“4”),new Button(“5”),new Button(“6”),new Button(“-“),

new Button(“1”),new Button(“2”),new Button(“3”),new Button(“*”),

new Button(“0”),new Button(“.”),new Button(“=”),new Button(“/”)};

private JPanel jpt=new JPanel();

private JPanel jpb=new JPanel();

private JTextField jtf=new JTextField(“”);

private MyCaculator(){

}

private void operate(String x){

}

public String add(String x){

return output;

}

public String subtract(String x){

return output;

}

public String multiply(String x){

return output;

}

public String divide(String x){

return output;

}

public String Equals(String x){

return output;

}

public void opClean(){

}

class setOperate_Act implements ActionListener{

public void actionPerformed(ActionEvent e) {

}

}

class setLabel_Act implements ActionListener{

public void actionPerformed(ActionEvent e) {

}

}

public static void main(String[] args) {

}

}

2.建立構造方法：

所謂構造方法就是，對自己的主類進行初始化，代碼如下：

private MyCaculator(){

jpt.setLayout(new BorderLayout());

jpt.add(jtf);

this.add(jpt,BorderLayout.NORTH);

jpb.setLayout(new GridLayout(4,4));

for(int i=0;ijba.length;i++){

jpb.add(jba[i]);

if(i==3||i==7||i==11||i==15||i==14)

jba[i].addActionListener(new setOperate_Act());

else

jba[i].addActionListener(new setLabel_Act());

}

this.add(jpb,BorderLayout.CENTER);

this.setSize(250, 200);

this.setResizable(false);

this.setVisible(true);

this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

}

3.建立數據計算方法

這裡的數據計算方法有6個，一個是主方法其他幾個是加減乘除的處理方法，代碼如下：

private void operate(String x){

double x1=Double.valueOf(x);

double y=Double.valueOf(output);

switch(op){

case 0:output=x;break;

case 1:output=String.valueOf(y+x1);break;

case 2:output =String.valueOf(y-x1);break;

case 3:output =String.valueOf(y*x1);break;

case 4:

if(x1!=0) output=String.valueOf(y/x1);

else output=”不能為0″;

break;

}

}

public String add(String x){

operate(x);

op=add;

return output;

}

public String subtract(String x){

operate(x);

op=sub;

return output;

}

public String multiply(String x){

operate(x);

op=mul;

return output;

}

public String divide(String x){

operate(x);

op=div;

return output;

}

public String Equals(String x){

operate(x);

op=0;

return output;

}

public void opClean(){

op=0;

output =”0″;

}

4.事件處理方法

這裡的時間處理方法，沒有建立一個整體的方法，二是在為了便於處理的方法，將按鈕事件分成兩個部分，並採用兩個子類來實現，這兩個類時內部類要寫在主類內部的，代碼如下：

class setOperate_Act implements ActionListener{

public void actionPerformed(ActionEvent e) {

if(e.getSource()==jba[3]){

jtf.setText(add(jtf.getText()));

ifOp=true;

}

else if(e.getSource()==jba[7]){

jtf.setText(subtract(jtf.getText()));

ifOp=true;

}

else if(e.getSource()==jba[11]){

jtf.setText(multiply(jtf.getText()));

ifOp=true;

}

else if(e.getSource()==jba[15]){

jtf.setText(divide(jtf.getText()));

ifOp=true;

}

else if(e.getSource()==jba[14]){

jtf.setText(Equals(jtf.getText()));

ifOp=true;

}

}

}

class setLabel_Act implements ActionListener{

public void actionPerformed(ActionEvent e) {

Button tempb=(Button)e.getSource();

if(ifOp){

jtf.setText(tempb.getLabel());

ifOp=false;

}else {

jtf.setText(jtf.getText()+tempb.getLabel());

}

}

}

5.建立main方法：

要想實現我們的代碼，我們需在main方法中，實例化我們的對象。

public static void main(String[] args) {

new MyCaculator();

}

編寫計算器java

僅供參考，最好自己親自動手寫，這樣才會有進步

import java.awt.BorderLayout;

import java.awt.Color;

import java.awt.GridLayout;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import javax.swing.ImageIcon;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JPanel;

import javax.swing.JTextField;

import javax.swing.SwingConstants;

public class Jisuanqi extends JFrame implements ActionListener {

/**

*

*/

private static final long serialVersionUID = 1L;

Result result = new Result(); // 定義text的面板

Number_Key number_key = new Number_Key(); // 定義按鈕面板

// 當點擊按鈕+、-、*、/時，com = true

boolean com = false;

// 當i=0時說明是我們第一次輸入，字元串text不會累加

int i = 0;

// 存放text的內容

String text = “”;

// 存放點擊按鈕+、-、*、/之前的數值

double defbutton = 0;

// +、-、*、/的代號分別為1，2，3，4

int symbol = 0;

// 構造函數

Jisuanqi() {

super(“WangJiao”); // 設定標題

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // 設定關閉窗體時退出程序

JPanel pane = new JPanel(); // 定義主面板

pane.setLayout(new BorderLayout());

setBounds(380, 220, 30, 80); // 前兩個參數是在屏幕上顯示的坐標，後兩個是大小

// 替換圖標

ImageIcon icon = new ImageIcon(“F:1.GIF”);

// Jisuanqi.class.getResource(“APPLE.GIF”)

// );

setIconImage(icon.getImage());

pane.add(result, BorderLayout.NORTH);

pane.add(number_key, BorderLayout.CENTER);

pane.add(number_key.equal, BorderLayout.SOUTH);

number_key.one.addActionListener(this); // 對1按鈕添加監聽事件

number_key.two.addActionListener(this); // 對2按鈕添加監聽事件

number_key.three.addActionListener(this); // 對3按鈕添加監聽事件

number_key.four.addActionListener(this); // 對4按鈕添加監聽事件

number_key.five.addActionListener(this); // 對5按鈕添加監聽事件

number_key.six.addActionListener(this); // 對6按鈕添加監聽事件

number_key.seven.addActionListener(this); // 對7按鈕添加監聽事件

number_key.eight.addActionListener(this); // 對8按鈕添加監聽事件

number_key.nine.addActionListener(this); // 對9按鈕添加監聽事件

number_key.zero.addActionListener(this); // 對0按鈕添加監聽事件

number_key.ce.addActionListener(this); // 對置零按鈕添加監聽事件

number_key.plus.addActionListener(this); // 對+按鈕添加監聽事件

number_key.equal.addActionListener(this); // 對=按鈕添加監聽事件

number_key.sub.addActionListener(this); // 對-按鈕添加監聽事件

number_key.mul.addActionListener(this); // 對*按鈕添加監聽事件

number_key.div.addActionListener(this); // 對/按鈕添加監聽事件

number_key.point.addActionListener(this); // 對.按鈕添加監聽事件

setContentPane(pane);

pack(); // 初始化窗體大小為正好盛放所有按鈕

}

// 各個按鈕觸發的事件

public void actionPerformed(ActionEvent e) {

/*

* 如果是點擊數字按鈕那麼先要判斷是否在此之前點擊了+、-、*、/、=，如果是那麼com=true 如果沒有com=

* false;或者是否點擊數字鍵，如果是i = 1,如果沒有 i = 0;

*/

if (e.getSource() == number_key.one) {

if (com || i == 0) {

result.text.setText(“1”);

com = false;

i = 1;

} else {

text = result.text.getText();

result.text.setText(text + “1”);

}

} else if (e.getSource() == number_key.two) {

if (com || i == 0) {

result.text.setText(“2”);

com = false;

i = 1;

} else {

text = result.text.getText();

result.text.setText(text + “2”);

}

} else if (e.getSource() == number_key.three) {

if (com || i == 0) {

result.text.setText(“3”);

com = false;

i = 1;

} else {

text = result.text.getText();

result.text.setText(text + “3”);

}

} else if (e.getSource() == number_key.four) {

if (com || i == 0) {

result.text.setText(“4”);

com = false;

i = 1;

} else {

text = result.text.getText();

result.text.setText(text + “4”);

}

} else if (e.getSource() == number_key.five) {

if (com || i == 0) {

result.text.setText(“5”);

com = false;

i = 1;

} else {

text = result.text.getText();

result.text.setText(text + “5”);

}

} else if (e.getSource() == number_key.six) {

if (com || i == 0) {

result.text.setText(“6”);

com = false;

i = 1;

} else {

text = result.text.getText();

result.text.setText(text + “6”);

}

} else if (e.getSource() == number_key.seven) {

if (com || i == 0) {

result.text.setText(“7”);

com = false;

i = 1;

} else {

text = result.text.getText();

result.text.setText(text + “7”);

}

} else if (e.getSource() == number_key.eight) {

if (com || i == 0) {

result.text.setText(“8”);

com = false;

i = 1;

} else {

text = result.text.getText();

result.text.setText(text + “8”);

}

} else if (e.getSource() == number_key.nine) {

if (com || i == 0) {

result.text.setText(“9”);

com = false;

i = 1;

} else {

text = result.text.getText();

result.text.setText(text + “9”);

}

}

/*

* 對於0這個按鈕有一定的說法，在我的程序里不會出現如00000這樣的情況，我加了判斷條件就是

* 如果text中的數值=0就要判斷在這個數值中是否有.存在?如果有那麼就在原來數值基礎之上添 加0;否則保持原來的數值不變

*/

else if (e.getSource() == number_key.zero) { // result.text.getText()是得到text里內容的意思

if (com || i == 0) {

result.text.setText(“0”);

com = false;

i = 1;

} else {

text = result.text.getText();

if (Float.parseFloat(text) 0 || Float.parseFloat(text) 0) { // Float.parseFloat(text)就是類型轉換了，下面都是一樣

result.text.setText(text + “0”);

} else {

if (text.trim().indexOf(“.”) == -1) {

result.text.setText(text);

} else {

result.text.setText(text + “0”);

}

}

}

} else if (e.getSource() == number_key.ce) {

result.text.setText(“0”);

i = 0;

com = true;

// text = “”;

defbutton = 0;

}

/*

* 本程序不會讓一個數值中出現2個以上的小數點.具體做法是:判斷是否已經存在.存在就不添加, 不存在就添加.

*/

else if (e.getSource() == number_key.point) {

if (com || i == 0) {

result.text.setText(“0.”);

com = false;

i = 1;

} else {

text = result.text.getText();

if (text.trim().indexOf(“.”) == -1) {

result.text.setText(text + “.”);

} else {

result.text.setText(text);

}

}

} // 獲得點擊+之前的數值

else if (e.getSource() == number_key.plus) {

com = true;

i = 0;

defbutton = Double.parseDouble(result.text.getText());

symbol = 1;

} // 獲得點擊-之前的數值

else if (e.getSource() == number_key.sub) {

com = true;

i = 0;

defbutton = Double.parseDouble(result.text.getText());

symbol = 2;

} // 獲得點擊*之前的數值

else if (e.getSource() == number_key.mul) {

com = true;

i = 0;

defbutton = Double.parseDouble(result.text.getText());

System.out.println(defbutton);

symbol = 3;

} // 獲得點擊/之前的數值

else if (e.getSource() == number_key.div) {

com = true;

i = 0;

defbutton = Double.parseDouble(result.text.getText());

symbol = 4;

} else if (e.getSource() == number_key.equal) {

switch (symbol) {

case 1: { // 計算加法

double ad = defbutton

+ Double.parseDouble(result.text.getText());

result.text.setText(ad + “”);

i = 0;

text = “”;

break;

}

case 2: { // 計算減法

double ad = defbutton

– Double.parseDouble(result.text.getText());

result.text.setText(String.valueOf(ad));

i = 0;

text = “”;

break;

}

case 3: { // 計算乘法

double ad = defbutton

* Double.parseDouble(result.text.getText());

result.text.setText(ad + “”);

i = 0;

text = “”;

break;

}

case 4: { // 計算除法

double ad = defbutton

/ Double.parseDouble(result.text.getText());

result.text.setText(ad + “”);

i = 0;

text = “”;

break;

}

}

System.out.println(com);

}

System.out.println(result.text.getText());

}

@SuppressWarnings(“deprecation”)

public static void main(String[] args) {

Jisuanqi loveyou = new Jisuanqi();

loveyou.show();

}

}

// 計算器數字按鈕定義面板

class Number_Key extends JPanel {

/**

*

*/

private static final long serialVersionUID = 1L;

JButton zero = new JButton(“0”); // 數字鍵0

JButton one = new JButton(“1”); // 數字鍵1

JButton two = new JButton(“2”); // 數字鍵2

JButton three = new JButton(“3”); // 數字鍵3

JButton four = new JButton(“4”); // 數字鍵4

JButton five = new JButton(“5”); // 數字鍵5

JButton six = new JButton(“6”); // 數字鍵6

JButton seven = new JButton(“7”); // 數字鍵7

JButton eight = new JButton(“8”); // 數字鍵8

JButton nine = new JButton(“9”); // 數字鍵9

JButton plus = new JButton(“+”);

JButton sub = new JButton(“-“);

JButton mul = new JButton(“*”);

JButton div = new JButton(“/”);

JButton equal = new JButton(“=”);

JButton ce = new JButton(“清零”); // 置零鍵

JButton point = new JButton(“.”);

Number_Key() {

setLayout(new GridLayout(4, 4, 1, 1)); // 定義布局管理器為網格布局

setBackground(Color.blue); // 設置背景顏色

// 添加按鈕

add(one);

add(two);

add(three);

add(four);

add(five);

add(six);

add(seven);

add(eight);

add(nine);

add(zero);

add(plus);

add(sub);

add(mul);

add(div);

add(point);

add(equal);

add(ce);

}

}

// 計算器顯示結果的窗體

class Result extends JPanel {

/**

*

*/

private static final long serialVersionUID = 1L;

// text先是輸入和結果

JTextField text = new JTextField(“0”);

@SuppressWarnings(“deprecation”)

Result() { // 講輸入的數字或得到的結果在text的右邊顯示

text.setHorizontalAlignment(SwingConstants.RIGHT);

text.enable(false); // 文本框不能編輯

setLayout(new BorderLayout()); // 設定布局管理器邊框布局

add(text, BorderLayout.CENTER); // text放置在窗體的中間

}

}