计算器实现了大部分基础功能：基本运算，菜单栏选项，并且拓展了普通型和科学兴选项等等，读者可以在此基础上进行修改和拓展。其他具体实现方法可以看源码，里面有详细的概述，代码框架清晰。
运行环境：win10 Eclipse IDE for Java Developers - 2020-06
下面是计算器的视图：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 |
import java.awt.*; import java.awt.event.ActionEvent; import java.awt.event.ActionListener;
import javax.swing.*;
/* * 计算器 */ public class CaculatorTest implements ActionListener { // 初始框架搭建 JFrame frame = new JFrame( "计算器" ); JTextField area = new JTextField( "0" ); JPanel panel1 = new JPanel(); JPanel panel2 = new JPanel(); JButton[] buttons = new JButton[ 20 ]; String[] buttonsText = { "sqrt" , "退格" , "C" , "/" , "7" , "8" , "9" , "*" , "4" , "5" , "6" , "-" , "1" , "2" , "3" , "+" , "0" , "." , "+/-" , "=" }; boolean point = false ; // 用于判断是否输入多位小数点 boolean key = true ; // 做完运算("=")后继续输入数字 String sign = " " ; // 用于判断和记录运算符号 double temp = 0 ; // 多次连续运算时，值的寄存处
public CaculatorTest() { initMenu(); initText(); initExtend(); initFrame(); initBorderLayout(); }
// 初始化菜单 private void initMenu() { JMenuBar mb = new JMenuBar(); JMenu m1 = new JMenu( "选项" ); JMenu m2 = new JMenu( "编辑" ); JMenu m3 = new JMenu( "帮助" ); JMenuItem m11 = new JMenuItem( "普通型计算器" ); JMenuItem m12 = new JMenuItem( "科学型计算器" ); m1.add(m11); m1.add(m12); m11.addActionListener( new ActionListener() { @Override public void actionPerformed(ActionEvent e) { boolean flag = false ; panel2.setVisible(flag); frame.pack(); } }); m12.addActionListener( new ActionListener() { @Override public void actionPerformed(ActionEvent e) { boolean flag = true ; panel2.setVisible(flag); frame.pack(); } }); mb.add(m1); mb.add(m2); mb.add(m3); frame.setJMenuBar(mb); }
// 初始化输出文本域 private void initText() { area.setFont( new Font( "TimesRoman" , Font.PLAIN, 20 )); area.setSize( 400 , 100 ); area.setHorizontalAlignment(JTextField.RIGHT); // 向右显示 }
// 初始化拓展功能 private void initExtend() { panel2.setLayout( new GridLayout( 1 , 4 , 1 , 1 )); JButton b1 = new JButton( "sin" ); JButton b2 = new JButton( "cos" ); JButton b3 = new JButton( "exp" ); JButton b4 = new JButton( "ln" ); b1.setFont( new Font( "TimesRoman" , Font.PLAIN, 20 )); b2.setFont( new Font( "TimesRoman" , Font.PLAIN, 20 )); b3.setFont( new Font( "TimesRoman" , Font.PLAIN, 20 )); b4.setFont( new Font( "TimesRoman" , Font.PLAIN, 20 )); b1.setSize( 100 , 100 ); b1.addActionListener( this ); b2.setSize( 100 , 100 ); b2.addActionListener( this ); b3.setSize( 100 , 100 ); b3.addActionListener( this ); b4.setSize( 100 , 100 ); b4.addActionListener( this ); panel2.add(b1); panel2.add(b2); panel2.add(b3); panel2.add(b4); }
// 初始化计算器基本界面 private void initFrame() { panel1.setLayout( new GridLayout( 5 , 4 , 1 , 1 )); for ( int i = 0 ; i < buttonsText.length; i++) { JButton button = new JButton(buttonsText[i]); button.setSize( 100 , 100 ); button.setFont( new Font( "TimesRoman" , Font.PLAIN, 20 )); button.addActionListener( this ); panel1.add(button); } }
// 初始化计算器总基本界面 private void initBorderLayout() { frame.setLayout( new BorderLayout()); frame.add(panel1, BorderLayout.SOUTH); // 插入组件 frame.add(area, BorderLayout.NORTH); frame.add(panel2, BorderLayout.CENTER); frame.setLocation( 700 , 400 ); frame.setSize( 400 , 700 ); frame.setVisible( true ); // 设置可见 panel2.setVisible( false ); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // 可以关闭 frame.pack(); }
public static void main(String[] args) { new CaculatorTest(); }
@Override // 事件监听 public void actionPerformed(ActionEvent e) { String str = e.getActionCommand(); String str2 = area.getText(); if (str == "0" || str == "1" || str == "2" || str == "3" || str == "4" || str == "5" || str == "6" || str == "7" || str == "8" || str == "9" ) { if (key == false ) { area.setText(str2 + str); } else { area.setText(str); key = false ; } } else if (str == "C" ) { area.setText( "0" ); sign = " " ; key = true ; } else if (str == "." ) { if (point == false ) { area.setText(str2 + str); point = true ; } else { area.setText( "double poits!press C to update!" ); point = false ; } } else if (str == "+/-" ) { double num = Double.valueOf(str2); num = -num; area.setText(String.valueOf(num)); } else if (str == "退格" ) { if (str2.length() == 0 ) { area.setText( "can't be deleted!please press C!" ); } else { str2 = str2.substring( 0 , str2.length() - 1 ); area.setText(str2); } } else if (str == "sqrt" ) { area.setText( "" ); sign = "s" ; } else if (str == "sin" ) { area.setText( "" ); sign = "sin" ; } else if (str == "cos" ) { area.setText( "" ); sign = "cos" ; } else if (str == "exp" ) { area.setText( "" ); sign = "exp" ; } else if (str == "ln" ) { area.setText( "" ); sign = "ln" ; } else { if (str == "+" ) { if (sign == " " ) { sign = "+" ; temp = Double.valueOf(str2); area.setText( "" ); } else if (sign == "-" ) { if (str2.length() == 0 ) { sign = "+" ; } else { temp = temp - Double.valueOf(str2); sign = "+" ; area.setText( "" ); key = true ; } } else if (sign == "+" ) { if (str2.length() == 0 ) { sign = "+" ; } else { temp = temp + Double.valueOf(str2); sign = "+" ; area.setText( "" ); key = true ; } } else if (sign == "*" ) { if (str2.length() == 0 ) { sign = "+" ; } else { temp = temp * Double.valueOf(str2); sign = "+" ; area.setText( "" ); key = true ; } } else if (sign == "/" ) { if (str2.length() == 0 ) { sign = "+" ; } else if (Double.valueOf(str2) == 0 ) { area.setText( "除数不能为0哦！按 C" ); } else { temp = temp / Double.valueOf(str2); area.setText( "" ); sign = "+" ; key = true ; } } else if (sign == "s" ) { if (str2.length() == 0 ) { sign = "+" ; } else { temp = Math.sqrt(Double.valueOf(str2)); area.setText( "" ); sign = "+" ; } } else if (sign == "sin" ) { if (str2.length() == 0 ) { sign = "+" ; } else { temp = Math.sin(Double.valueOf(str2)); area.setText( "" ); sign = "+" ; } } else if (sign == "cos" ) { if (str2.length() == 0 ) { sign = "+" ; } else { temp = Math.cos(Double.valueOf(str2)); area.setText( "" ); sign = "+" ; } } else if (sign == "exp" ) { if (str2.length() == 0 ) { sign = "+" ; } else { temp = Math.exp(Double.valueOf(str2)); area.setText( "" ); sign = "+" ; } } else if (sign == "ln" ) { if (str2.length() == 0 ) { sign = "+" ; } else { temp = Math.log(Double.valueOf(str2)); area.setText( "" ); sign = "+" ; } } } else if (str == "-" ) { if (sign == " " ) { sign = "-" ; temp = Double.valueOf(str2); area.setText( "" ); } else if (sign == "-" ) { if (str2.length() == 0 ) { sign = "-" ; } else { temp = temp - Double.valueOf(str2); sign = "-" ; area.setText( "" ); key = true ; } } else if (sign == "+" ) { if (str2.length() == 0 ) { sign = "-" ; } else { temp = temp + Double.valueOf(str2); sign = "-" ; area.setText( "" ); key = true ; } } else if (sign == "*" ) { if (str2.length() == 0 ) { sign = "-" ; } else { temp = temp * Double.valueOf(str2); sign = "-" ; area.setText( "" ); key = true ; } } else if (sign == "/" ) { if (str2.length() == 0 ) { sign = "-" ; } else if (Double.valueOf(str2) == 0 ) { area.setText( "除数不能为0哦！按 C" ); } else { temp = temp / Double.valueOf(str2); area.setText( "" ); sign = "-" ; key = true ; } } else if (sign == "s" ) { if (str2.length() == 0 ) { sign = "-" ; } else { temp = Math.sqrt(Double.valueOf(str2)); area.setText( "" ); sign = "-" ; } } else if (sign == "sin" ) { if (str2.length() == 0 ) { sign = "-" ; } else { temp = Math.sin(Double.valueOf(str2)); area.setText( "" ); sign = "-" ; } } else if (sign == "cos" ) { if (str2.length() == 0 ) { sign = "-" ; } else { temp = Math.cos(Double.valueOf(str2)); area.setText( "" ); sign = "-" ; } } else if (sign == "exp" ) { if (str2.length() == 0 ) { sign = "-" ; } else { temp = Math.exp(Double.valueOf(str2)); area.setText( "" ); sign = "-" ; } } else if (sign == "ln" ) { if (str2.length() == 0 ) { sign = "-" ; } else { temp = Math.log(Double.valueOf(str2)); area.setText( "" ); sign = "-" ; } } } else if (str == "*" ) { if (sign == " " ) { sign = "*" ; temp = Double.valueOf(str2); area.setText( "" ); } else if (sign == "-" ) { if (str2.length() == 0 ) { sign = "*" ; } else { temp = temp - Double.valueOf(str2); sign = "*" ; area.setText( "" ); key = true ; } } else if (sign == "+" ) { if (str2.length() == 0 ) { sign = "*" ; } else { temp = temp + Double.valueOf(str2); sign = "*" ; area.setText( "" ); key = true ; } } else if (sign == "*" ) { if (str2.length() == 0 ) { sign = "*" ; } else { temp = temp * Double.valueOf(str2); sign = "*" ; area.setText( "" ); key = true ; } } else if (sign == "/" ) { if (str2.length() == 0 ) { sign = "*" ; } else if (Double.valueOf(str2) == 0 ) { area.setText( "除数不能为0哦！按 C" ); } else { temp = temp / Double.valueOf(str2); area.setText( "" ); sign = "*" ; key = true ; } } else if (sign == "s" ) { if (str2.length() == 0 ) { sign = "*" ; } else { temp = Math.sqrt(Double.valueOf(str2)); area.setText( "" ); sign = "*" ; } } else if (sign == "sin" ) { if (str2.length() == 0 ) { sign = "*" ; } else { temp = Math.sin(Double.valueOf(str2)); area.setText( "" ); sign = "*" ; } } else if (sign == "cos" ) { if (str2.length() == 0 ) { sign = "*" ; } else { temp = Math.cos(Double.valueOf(str2)); area.setText( "" ); sign = "*" ; } } else if (sign == "exp" ) { if (str2.length() == 0 ) { sign = "*" ; } else { temp = Math.exp(Double.valueOf(str2)); area.setText( "" ); sign = "*" ; } } else if (sign == "ln" ) { if (str2.length() == 0 ) { sign = "*" ; } else { temp = Math.log(Double.valueOf(str2)); area.setText( "" ); sign = "*" ; } } } else if (str == "/" ) { if (sign == " " ) { sign = "/" ; temp = Double.valueOf(str2); area.setText( "" ); } else if (sign == "-" ) { if (str2.length() == 0 ) { sign = "/" ; } else { temp = temp - Double.valueOf(str2); sign = "/" ; area.setText( "" ); key = true ; } } else if (sign == "+" ) { if (str2.length() == 0 ) { sign = "/" ; } else { temp = temp + Double.valueOf(str2); sign = "/" ; area.setText( "" ); key = true ; } } else if (sign == "*" ) { if (str2.length() == 0 ) { sign = "/" ; } else { temp = temp * Double.valueOf(str2); sign = "/" ; area.setText( "" ); key = true ; } } else if (sign == "/" ) { if (str2.length() == 0 ) { sign = "/" ; } else if (Double.valueOf(str2) == 0 ) { area.setText( "除数不能为0哦！按 C" ); } else { temp = temp / Double.valueOf(str2); area.setText( "" ); sign = "/" ; key = true ; } } else if (sign == "s" ) { if (str2.length() == 0 ) { sign = "/" ; } else { temp = Math.sqrt(Double.valueOf(str2)); area.setText( "" ); sign = "/" ; } } else if (sign == "sin" ) { if (str2.length() == 0 ) { sign = "/" ; } else { temp = Math.sin(Double.valueOf(str2)); area.setText( "" ); sign = "/" ; } } else if (sign == "cos" ) { if (str2.length() == 0 ) { sign = "/" ; } else { temp = Math.cos(Double.valueOf(str2)); area.setText( "" ); sign = "/" ; } } else if (sign == "exp" ) { if (str2.length() == 0 ) { sign = "/" ; } else { temp = Math.exp(Double.valueOf(str2)); area.setText( "" ); sign = "/" ; } } else if (sign == "ln" ) { if (str2.length() == 0 ) { sign = "/" ; } else { temp = Math.log(Double.valueOf(str2)); area.setText( "" ); sign = "/" ; } } } else if (str == "=" ) { if (sign == "+" ) { if (str2.length() == 0 ) { area.setText(String.valueOf(temp)); sign = " " ; } else { temp = temp + Double.valueOf(str2); area.setText(String.valueOf(temp)); sign = " " ; } } else if (sign == "-" ) { if (str2.length() == 0 ) { area.setText(String.valueOf(temp)); sign = " " ; } else { temp = temp - Double.valueOf(str2); area.setText(String.valueOf(temp)); sign = " " ; } } else if (sign == "*" ) { if (str2.length() == 0 ) { area.setText(String.valueOf(temp)); sign = " " ; } else { temp = temp * Double.valueOf(str2); area.setText(String.valueOf(temp)); sign = " " ; } } else if (sign == "/" ) { if (Double.valueOf(str2) == 0 ) { area.setText( "除数不能为0哦！按C" ); sign = " " ; } else { temp = temp / Double.valueOf(str2); area.setText(String.valueOf(temp)); sign = " " ; } } else if (sign == " " ) { if (str2.length() == 0 ) { area.setText(String.valueOf(temp)); } else { temp = Double.valueOf(str2); area.setText(String.valueOf(temp)); } } else if (sign == "s" ) { temp = Math.sqrt(Double.valueOf(str2)); area.setText(String.valueOf(temp)); sign = " " ; } else if (sign == "sin" ) { temp = Math.sin(Double.valueOf(str2)); area.setText(String.valueOf(temp)); sign = " " ; } else if (sign == "cos" ) { temp = Math.cos(Double.valueOf(str2)); area.setText(String.valueOf(temp)); sign = " " ; } else if (sign == "exp" ) { temp = Math.exp(Double.valueOf(str2)); area.setText(String.valueOf(temp)); sign = " " ; } else if (sign == "ln" ) { temp = Math.log(Double.valueOf(str2)); area.setText(String.valueOf(temp)); sign = " " ; } key = true ; } } } } |
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。
原文链接：https://blog.csdn.net/wlfyok/article/details/111083332