Android开发实现的简单计算器功能【附完整demo源码下载】

本文实例讲述了android开发实现的简单计算器功能。分享给大家供大家参考，具体如下：

这个android计算器虽然还有点小bug，不过简单的计算功能还是没问题的哦；

先上图看效果

比较简单，所以我就没怎么写注释，应该一看就能明白的
有不明白的可以发信问我

先贴mainactivity.java代码

package com.example.calculator;
import android.app.activity;
import android.os.bundle;
import android.view.menu;
import android.view.menuitem;
import android.view.view;
import android.view.view.onclicklistener;
import android.widget.button;
import android.widget.edittext;
import android.widget.imageview;
import android.widget.textview;
import android.widget.toast;
public class mainactivity extends activity implements onclicklistener {
  button b1, b2, b3, b4, b5, b6, b7, b8, b9, b0, bp, bs, bm, bd, bc, be;
  imageview delete;
  textview tv;
  edittext show;
  string showstring = "", option = "";
  int showfirst = 0;
  string exception = "";
  @override
  protected void oncreate(bundle savedinstancestate) {
    super.oncreate(savedinstancestate);
    setcontentview(r.layout.activity_main);
    b0 = (button) findviewbyid(r.id.bt_0);
    b1 = (button) findviewbyid(r.id.bt_1);
    b2 = (button) findviewbyid(r.id.bt_2);
    b3 = (button) findviewbyid(r.id.bt_3);
    b4 = (button) findviewbyid(r.id.bt_4);
    b5 = (button) findviewbyid(r.id.bt_5);
    b6 = (button) findviewbyid(r.id.bt_6);
    b7 = (button) findviewbyid(r.id.bt_7);
    b8 = (button) findviewbyid(r.id.bt_8);
    b9 = (button) findviewbyid(r.id.bt_9);
    bp = (button) findviewbyid(r.id.bt_plus);
    bs = (button) findviewbyid(r.id.bt_sub);
    bm = (button) findviewbyid(r.id.bt_mutilate);
    bd = (button) findviewbyid(r.id.bt_div);
    bc = (button) findviewbyid(r.id.bt_c);
    be = (button) findviewbyid(r.id.bt_equ);
    b1.setonclicklistener(this);
    b2.setonclicklistener(this);
    b3.setonclicklistener(this);
    b4.setonclicklistener(this);
    b5.setonclicklistener(this);
    b6.setonclicklistener(this);
    b7.setonclicklistener(this);
    b8.setonclicklistener(this);
    b9.setonclicklistener(this);
    b0.setonclicklistener(this);
    bp.setonclicklistener(this);
    bs.setonclicklistener(this);
    bm.setonclicklistener(this);
    bd.setonclicklistener(this);
    bc.setonclicklistener(this);
    be.setonclicklistener(this);
    show = (edittext) findviewbyid(r.id.et_show);
    delete = (imageview) findviewbyid(r.id.iv_delete);
    delete.setonclicklistener(this);
    tv=(textview) findviewbyid(r.id.author);
    tv.setonclicklistener(this);
  }
  @override
  public boolean oncreateoptionsmenu(menu menu) {
    // inflate the menu; this adds items to the action bar if it is present.
    getmenuinflater().inflate(r.menu.main, menu);
    return true;
  }
  @override
  public boolean onoptionsitemselected(menuitem item) {
    // handle action bar item clicks here. the action bar will
    // automatically handle clicks on the home/up button, so long
    // as you specify a parent activity in androidmanifest.xml.
    int id = item.getitemid();
    if (id == r.id.action_settings) {
      return true;
    }
    return super.onoptionsitemselected(item);
  }
  @override
  public void onclick(view v) {
    switch (v.getid()) {
    case r.id.bt_0:
      showstring += "0";
      break;
    case r.id.bt_1:
      showstring += "1";
      break;
    case r.id.bt_2:
      showstring += "2";
      break;
    case r.id.bt_3:
      showstring += "3";
      break;
    case r.id.bt_4:
      showstring += "4";
      break;
    case r.id.bt_5:
      showstring += "5";
      break;
    case r.id.bt_6:
      showstring += "6";
      break;
    case r.id.bt_7:
      showstring += "7";
      break;
    case r.id.bt_8:
      showstring += "8";
      break;
    case r.id.bt_9:
      showstring += "9";
      break;
    case r.id.bt_plus:
      if (showstring.equals(""))
        exception = "先输入数值哦";
      else {
        showfirst = integer.parseint(showstring);
        showstring = "";
        option = "+";
      }
      break;
    case r.id.bt_sub:
      if (showstring.equals(""))
        exception = "先输入数值哦";
      else {
        showfirst = integer.parseint(showstring);
        showstring = "";
        option = "-";
      }
      break;
    case r.id.bt_mutilate:
      if (showstring.equals(""))
        exception = "先输入数值哦";
      else {
        showfirst = integer.parseint(showstring);
        showstring = "";
        option = "*";
      }
      break;
    case r.id.bt_div:
      if (showstring.equals(""))
        exception = "先输入数值哦";
      else {
        showfirst = integer.parseint(showstring);
        showstring = "";
        option = "/";
      }
      break;
    case r.id.bt_equ:
      if (option.equals("+"))
        showstring = showfirst + integer.parseint(showstring) + "";
      else if (option.equals("-")) {
        showstring = showfirst - integer.parseint(showstring) + "";
      } else if (option.equals("*")) {
        showstring = showfirst * integer.parseint(showstring) + "";
      } else if (option.equals("/")) {
        if (showstring.equals("0")) {
          exception = "除数不能为0！";
        } else
          showstring = showfirst / integer.parseint(showstring) + "";
      }
      break;
    case r.id.bt_c:
      showstring = "";
      break;
    case r.id.iv_delete:
      toast.maketext(mainactivity.this, showstring + "已被清空",
          toast.length_short).show();
      showstring = "";
      break;
    case r.id.author:
      toast.maketext(mainactivity.this, "郑明亮\n软件工程\nqq：1072307340",
          toast.length_short).show();
      break;
    default:
      break;
    }
    if (exception.equals(""))
      show.settext(showstring);
    else {
      show.settext(exception);
      exception = "";
    }
    // 设置文本框颜色；
    if (!show.gettext().tostring().equals("")) {
      delete.setbackgroundcolor(r.drawable.delete_gray);
    }
    else {
      delete.setbackgroundresource(r.drawable.delete);
    }
  }
}

再贴布局activity_main.xml：

<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical"
  tools:context="com.example.calculator.mainactivity" >
  <relativelayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >
    <edittext
      android:id="@+id/et_show"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:hint="请输入数字" />
    <imageview
      android:id="@+id/iv_delete"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_alignright="@id/et_show"
      android:src="@drawable/delete_and_deletegray" >
    </imageview>
  </relativelayout>
  <gridlayout
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_below="@+id/et_show"
    android:focusable="false"
    android:gravity="center"
    android:layout_margintop="25dp"
    android:columncount="4"
    android:horizontalspacing="0dp"
    android:orientation="horizontal"
    android:stretchmode="none" >
    <button
      android:id="@+id/bt_1"
      android:layout_height="wrap_content"
      android:text="1" />
    <button
      android:id="@+id/bt_2"
      android:text="2" />
    <button
      android:id="@+id/bt_3"
      android:text="3" />
    <button
      android:id="@+id/bt_div"
      android:text="/" />
    <button
      android:id="@+id/bt_4"
      android:text="4" />
    <button
      android:id="@+id/bt_5"
      android:text="5" />
    <button
      android:id="@+id/bt_6"
      android:text="6" />
    <button
      android:id="@+id/bt_mutilate"
      android:text="x" />
    <button
      android:id="@+id/bt_7"
      android:text="7" />
    <button
      android:id="@+id/bt_8"
      android:text="8" />
    <button
      android:id="@+id/bt_9"
      android:text="9" />
    <button
      android:id="@+id/bt_sub"
      android:text="-" />
    <button
      android:id="@+id/bt_0"
      android:layout_columnspan="2"
      android:layout_gravity="fill_horizontal"
      android:text="0"
      android:width="2dp" />
    <button
      android:id="@+id/bt_c"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:text="c" />
    <button
      android:id="@+id/bt_plus"
      android:layout_gravity="fill_vertical"
      android:layout_rowspan="2"
      android:text="+" />
    <button
      android:id="@+id/bt_equ"
      android:layout_columnspan="3"
      android:layout_gravity="fill_horizontal"
      android:text="=" />
  </gridlayout>
  <textview
    android:id="@+id/author"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="author:bri"
    />
  <textview
    android:id="@+id/test"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="test:www.jb51.net"
    />
</linearlayout>

我还写了一个drawable的xml，自己看吧

delete_and_deletegray.xml：

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
  <item android:drawable="@drawable/delete_gray" android:state_focused="false" android:state_pressed="false"></item>
  <item android:drawable="@drawable/delete" android:state_focused="false" android:state_pressed="false" android:state_selected="true"/>
  <item android:drawable="@drawable/delete" android:state_pressed="true" android:state_selected="false"/>
  <item android:drawable="@drawable/delete" android:state_focused="true" android:state_pressed="true"/>
</selector>

附：完整实例代码点击此处本站下载。

ps：这里再为大家推荐几款计算工具供大家进一步参考借鉴：

在线一元函数（方程）求解计算工具：

科学计算器在线使用_高级计算器在线计算：

在线计算器_标准计算器：

更多关于android相关内容感兴趣的读者可查看本站专题：《android开发入门与进阶教程》、《android基本组件用法总结》、《android视图view技巧总结》、《android布局layout技巧总结》及《android控件用法总结》

希望本文所述对大家android程序设计有所帮助。