Android Studio实现计算器功能

实验一：做一个简单的计算器

1.创建布局文件Activity_main.xml

代码如下：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="vertical"android:layout_width="match_parent"android:layout_height="match_parent"><EditTextandroid:id="@+id/result"android:layout_width="match_parent"android:layout_height="wrap_content"android:textSize="40sp"android:enabled="false"/><LinearLayoutandroid:layout_width="match_parent"android:layout_height="0dp"android:layout_weight="1"android:orientation="horizontal"><Buttonandroid:id="@+id/cls"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="C"android:textColor="#ffffff"/><Buttonandroid:id="@+id/div"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="/"android:textColor="#ffffff"/><Buttonandroid:id="@+id/mul"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="*"android:textColor="#ffffff"/><Buttonandroid:id="@+id/Backspace"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="Backspace"android:textAllCaps="false"android:textColor="#ffffff"/></LinearLayout><LinearLayoutandroid:layout_width="match_parent"android:layout_height="0dp"android:layout_weight="1"android:orientation="horizontal"><Buttonandroid:id="@+id/seven"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="7"android:textColor="#ffffff"/><Buttonandroid:id="@+id/eight"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="8"android:textColor="#ffffff"/><Buttonandroid:id="@+id/nine"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="9"android:textColor="#ffffff"/><Buttonandroid:id="@+id/sub"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="-"android:textColor="#ffffff"/></LinearLayout><LinearLayoutandroid:layout_width="match_parent"android:layout_height="0dp"android:layout_weight="1"android:orientation="horizontal"><Buttonandroid:id="@+id/four"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="4"android:textColor="#ffffff"/><Buttonandroid:id="@+id/five"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="5"android:textColor="#ffffff"/><Buttonandroid:id="@+id/six"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="6"android:textColor="#ffffff"/><Buttonandroid:id="@+id/add"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="+"android:textColor="#ffffff"/></LinearLayout><LinearLayoutandroid:layout_width="match_parent"android:layout_height="0dp"android:layout_weight="2"android:orientation="horizontal"><LinearLayoutandroid:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:orientation="vertical"><LinearLayoutandroid:layout_width="match_parent"android:layout_height="1dp"android:layout_weight="1"android:orientation="horizontal"><Buttonandroid:id="@+id/one"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="1"android:textColor="#ffffff"/><Buttonandroid:id="@+id/two"android:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:textSize="20sp"android:text="2"android:textColor="#ffffff"/></LinearLayout><LinearLayoutandroid:layout_width="match_parent"android:layout_height="1dp"android:layout_weight="1"><Buttonandroid:id="@+id/zero"android:layout_width="match_parent"android:layout_height="match_parent"android:text="0"android:textSize="20sp"android:textColor="#ffffff"/></LinearLayout></LinearLayout><LinearLayoutandroid:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:orientation="horizontal"><LinearLayoutandroid:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"android:orientation="vertical"><Buttonandroid:id="@+id/three"android:layout_width="match_parent"android:layout_height="1dp"android:layout_weight="1"android:text="3"android:textSize="20sp"android:textColor="#ffffff"/><Buttonandroid:id="@+id/spot"android:layout_width="match_parent"android:layout_height="1dp"android:layout_weight="1"android:text="."android:textSize="20sp"android:textColor="#ffffff"/></LinearLayout><LinearLayoutandroid:layout_width="0dp"android:layout_height="match_parent"android:layout_weight="1"><Buttonandroid:id="@+id/equal"android:layout_width="match_parent"android:layout_height="match_parent"android:text="="android:textSize="20sp"android:textColor="#ffffff"/></LinearLayout></LinearLayout></LinearLayout>
</LinearLayout>

2.创建Java文件ActivityMain.java

代码如下：

package com.example.a86761.zdj003;    #换自己的工程名
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.List;public class MainActivity extends AppCompatActivity{private  StringBuilder show_equation=new StringBuilder();//显示运算式private  ArrayList calculate_equation;//计算式private  int signal=0;//为0 时表示刚输入状态；为1 时表示当前在输出结果上继续输入@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);//初始化show_equation=new StringBuilder();calculate_equation=new ArrayList<>();Button zero=(Button)findViewById(R.id.zero);Button one=(Button)findViewById(R.id.one);Button two=(Button)findViewById(R.id.two);Button three=(Button)findViewById(R.id.three);Button four=(Button)findViewById(R.id.four);Button five=(Button)findViewById(R.id.five);Button six=(Button)findViewById(R.id.six);Button seven=(Button)findViewById(R.id.seven);Button eight=(Button)findViewById(R.id.eight);Button nine=(Button)findViewById(R.id.nine);Button cls=(Button)findViewById(R.id.cls);Button div=(Button)findViewById(R.id.div);Button mul=(Button)findViewById(R.id.mul);Button backspace=(Button)findViewById(R.id.Backspace);Button sub=(Button)findViewById(R.id.sub);Button add=(Button)findViewById(R.id.add);final Button equal=(Button)findViewById(R.id.equal);final Button point=(Button)findViewById(R.id.spot);final EditText result=(EditText)findViewById(R.id.result);result.setCursorVisible(true);disableShowInput(result);//点击文本框时光标始终在文本末尾result.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {result.setSelection(result.getText().length());}});zero.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v){if(!(show_equation.toString().equals("0"))){if(signal==0){show_equation.append("0");result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());show_equation.append("0");result.setText(show_equation);result.setSelection(result.getText().length());signal=0;}}}});one.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(signal==0){show_equation.append("1");result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());show_equation.append("1");result.setText(show_equation);result.setSelection(result.getText().length());signal=0;}}});two.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(signal==0){show_equation.append("2");result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());show_equation.append("2");result.setText(show_equation);result.setSelection(result.getText().length());signal=0;}}});three.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(signal==0){show_equation.append("3");result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());show_equation.append("3");result.setText(show_equation);result.setSelection(result.getText().length());signal=0;}}});four.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(signal==0){show_equation.append("4");result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());show_equation.append("4");result.setText(show_equation);result.setSelection(result.getText().length());signal=0;}}});five.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(signal==0){show_equation.append("5");result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());show_equation.append("5");result.setText(show_equation);result.setSelection(result.getText().length());signal=0;}}});six.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(signal==0){show_equation.append("6");result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());show_equation.append("6");result.setText(show_equation);result.setSelection(result.getText().length());signal=0;}}});seven.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(signal==0){show_equation.append("7");result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());show_equation.append("7");result.setText(show_equation);result.setSelection(result.getText().length());signal=0;}}});eight.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(signal==0){show_equation.append("8");result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());show_equation.append("8");result.setText(show_equation);result.setSelection(result.getText().length());signal=0;}}});nine.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(signal==0){show_equation.append("9");result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());show_equation.append("9");result.setText(show_equation);result.setSelection(result.getText().length());signal=0;}}});cls.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {show_equation.delete(0,show_equation.length());calculate_equation.clear();signal=0;result.setText("");}});backspace.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(!(show_equation.toString().equals(""))) {if(signal==0){show_equation.deleteCharAt(show_equation.length() - 1);result.setText(show_equation);result.setSelection(result.getText().length());}else{show_equation.delete(0,show_equation.length());result.setText("");signal=0;}}}});point.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if(signal==0){String a=show_equation.toString();if(a.equals("")){show_equation.append(".");result.setText(show_equation);result.setSelection(result.getText().length());}else{int i;char t='0';for(i=a.length();i>0;i--){t=a.charAt(i-1);if(t=='.'||t=='+'||t=='-'||t=='*'||t=='/')break;}if(i==0){show_equation.append(".");result.setText(show_equation);result.setSelection(result.getText().length());}else if(t=='+'||t=='-'||t=='*'||t=='/'){show_equation.append(".");result.setText(show_equation);result.setSelection(result.getText().length());}}}else{show_equation.delete(0,show_equation.length());show_equation.append(".");result.setText(".");result.setSelection(result.getText().length());signal=0;}}});equal.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {//判断用户是否输入了内容if(!show_equation.toString().equals("")){signal=1;char temp=show_equation.charAt(show_equation.length()-1);if(show_equation.charAt(0)=='-')show_equation.insert(0,"0");if(temp=='+'||temp=='-')show_equation.append("0");if(temp=='*'||temp=='/')show_equation.append("1");StringBuilder temp1=new StringBuilder();for(int i=0;i<show_equation.length();i++){if(show_equation.charAt(i)>='0'&&show_equation.charAt(i)<='9'||show_equation.charAt(i)=='.'){temp1.append(String.valueOf(show_equation.charAt(i)));}else if(show_equation.charAt(i)=='N'){calculate_equation.add("NaN");//跳过2个字符i=i+2;}else if(show_equation.charAt(i)=='∞'){calculate_equation.add("∞");}else{if(temp1.length()!=0){calculate_equation.add(temp1.toString());temp1.delete(0,temp1.length());}calculate_equation.add(String.valueOf(show_equation.charAt(i)));}}if(temp1.length()!=0){calculate_equation.add(temp1.toString());}calculate_equation.add("#");String temp8=calculate(calculate_equation);result.setText(temp8);result.setSelection(result.getText().length());show_equation.delete(0,show_equation.length());calculate_equation.clear();show_equation.append(temp8);}}});add.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {//判断用户是否输入了内容if(!(show_equation.toString().equals(""))) {signal=0;char temp=show_equation.charAt(show_equation.length()-1);if(temp=='+'||temp=='-'||temp=='*'||temp=='/'){show_equation.deleteCharAt(show_equation.length()-1);show_equation.append("+");}elseshow_equation.append("+");result.setText(show_equation);result.setSelection(result.getText().length());}}});sub.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {//判断用户是否输入了内容if(!(show_equation.toString().equals(""))) {signal=0;char temp=show_equation.charAt(show_equation.length()-1);if(temp=='+'||temp=='-'||temp=='*'||temp=='/'){show_equation.deleteCharAt(show_equation.length()-1);show_equation.append("-");}elseshow_equation.append("-");result.setText(show_equation);result.setSelection(result.getText().length());}}});mul.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {//判断用户是否输入了内容if(!(show_equation.toString().equals(""))) {signal=0;char temp=show_equation.charAt(show_equation.length()-1);if(temp=='+'||temp=='-'||temp=='*'||temp=='/'){show_equation.deleteCharAt(show_equation.length()-1);show_equation.append("*");}elseshow_equation.append("*");result.setText(show_equation);result.setSelection(result.getText().length());}}});div.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {//判断用户是否输入了内容if(!(show_equation.toString().equals(""))) {signal=0;char temp=show_equation.charAt(show_equation.length()-1);if(temp=='+'||temp=='-'||temp=='*'||temp=='/'){show_equation.deleteCharAt(show_equation.length()-1);show_equation.append("/");}elseshow_equation.append("/");result.setText(show_equation);result.setSelection(result.getText().length());}}});}protected boolean operatorPriorityCompare(char operator1,char operator2){int o1=0;int o2=0;switch (operator1){case '+':{o1=0;break;}case '-':{o1=0;break;}case '*':{o1=1;break;}case '/':{o1=1;break;}}switch (operator2){case '+':{o2=0;break;}case '-':{o2=0;break;}case '*':{o2=1;break;}case '/':{o2=1;break;}}if(o1<=o2){return false;}elsereturn true;}//相加public static Double Add(Double d1,Double d2) {if(d1==Double.NEGATIVE_INFINITY||d1==Double.POSITIVE_INFINITY||d2==Double.NEGATIVE_INFINITY||d2==Double.POSITIVE_INFINITY){return d1+d2;}if(String.valueOf(d1).equals("NaN")||String.valueOf(d1).equals("NaN")){return d1+d2;}BigDecimal b1 = new BigDecimal(Double.toString(d1));BigDecimal b2 = new BigDecimal(Double.toString(d2));return b1.add(b2).doubleValue();}//相减public static Double Sub(Double d1,Double d2){if(d1==Double.NEGATIVE_INFINITY||d1==Double.POSITIVE_INFINITY||d2==Double.NEGATIVE_INFINITY||d2==Double.POSITIVE_INFINITY){return d1-d2;}if(String.valueOf(d1).equals("NaN")||String.valueOf(d1).equals("NaN")){return d1-d2;}if(String.valueOf(d1).equals("NaN")||String.valueOf(d1).equals("NaN")){return d1*d2;}BigDecimal b1=new BigDecimal(Double.toString(d1));BigDecimal b2=new BigDecimal(Double.toString(d2));return b1.subtract(b2).doubleValue();}//相乘public static Double Mul(Double d1,Double d2){if(d1==Double.NEGATIVE_INFINITY||d1==Double.POSITIVE_INFINITY||d2==Double.NEGATIVE_INFINITY||d2==Double.POSITIVE_INFINITY){return d1*d2;}if(String.valueOf(d1).equals("NaN")||String.valueOf(d1).equals("NaN")){return d1*d2;}BigDecimal b1=new BigDecimal(Double.toString(d1));BigDecimal b2=new BigDecimal(Double.toString(d2));return b1.multiply(b2).setScale(8).doubleValue();}//相除public static Double Div(Double d1,Double d2){if(d1==Double.NEGATIVE_INFINITY||d1==Double.POSITIVE_INFINITY||d2==Double.NEGATIVE_INFINITY||d2==Double.POSITIVE_INFINITY){return d1/d2;}if(String.valueOf(d1).equals("NaN")||String.valueOf(d1).equals("NaN")){return d1/d2;}if(d1==0.0&&d2==0.0){return Double.NaN;}if(d2==0.0){return d1/d2;}BigDecimal b1=new BigDecimal(Double.toString(d1));BigDecimal b2=new BigDecimal(Double.toString(d2));return b1.divide(b2,8,BigDecimal.ROUND_HALF_UP).doubleValue();}protected String calculate(ArrayList equation){Double temp2;Double temp3;Double result;List operator=new ArrayList();List<Double> operand=new ArrayList();for(int i=0;i<equation.size();i++){String temp4=(String) equation.get(i);if(temp4.equals("+")||temp4.equals("-")||temp4.equals("*")||temp4.equals("/")){if(operator.size()>0){String temp5=operator.get(operator.size()-1).toString();while(!(operatorPriorityCompare(temp4.charAt(0),temp5.charAt(0)))&&operator.size()>0){operator.remove(operator.size()-1);temp3=operand.get(operand.size()-1);operand.remove(operand.size()-1);temp2=operand.get(operand.size()-1);operand.remove(operand.size()-1);switch (temp5.charAt(0)){case '+':{result=Add(temp2,temp3);operand.add(result);break;}case '-':{result=Sub(temp2,temp3);operand.add(result);break;}case '*':{result=Mul(temp2,temp3);operand.add(result);break;}case '/':{result=Div(temp2,temp3);operand.add(result);break;}}if(operator.size()>0){temp5=operator.get(operator.size()-1).toString();}elsebreak;}operator.add(temp4);}elseoperator.add(temp4);}else if(temp4.equals("#")){while(operator.size()>0){String temp6=(String)operator.get(operator.size()-1);operator.remove(operator.size()-1);temp3=operand.get(operand.size()-1);operand.remove(operand.size()-1);temp2=operand.get(operand.size()-1);operand.remove(operand.size()-1);switch (temp6.charAt(0)){case '+':{result=Add(temp2,temp3);operand.add(result);break;}case '-':{result=Sub(temp2,temp3);operand.add(result);break;}case '*':{result=Mul(temp2,temp3);operand.add(result);break;}case '/':{result=Div(temp2,temp3);operand.add(result);break;}}}}else{if(temp4.equals("NaN")){operand.add(Double.NaN);}else if(temp4.equals("∞")){operand.add(Double.POSITIVE_INFINITY);}else{operand.add(Double.parseDouble(temp4));}}}if(operand.get(0)==Double.NEGATIVE_INFINITY) return "-∞";if(operand.get(0)==Double.POSITIVE_INFINITY) return "∞";return operand.get(0).toString();}//当API最低版小于21时使用这个函数实现点击文本框不弹出键盘public void disableShowInput(EditText et) {Class<EditText> cls = EditText.class;Method method;try {method = cls.getMethod("setShowSoftInputOnFocus", boolean.class);method.setAccessible(true);method.invoke(et, false);} catch (Exception e) {e.printStackTrace();}}
}

运行截图：

Android Studio实现计算器功能相关推荐

初学编程第一个小程序Android studio实现计算器功能
源代码下载:https://gitee.com/zha-yingying/calculator.git 1.建立一个新的Layout,我这里使用的是GridLayout(网格布局),提取屏幕宽度(方便 ...
Android Studio 3.4功能
Android Studio 3.4 is now available in stable channel. You can download it from here. In this quick ...
Android Studio 3.3功能
Android Studio 3.3 is the latest stable release. In this tutorial, we'll discuss the new features av ...
Android studio制作计算器源代码
版权声明:本文为博主原创文章,未经博主允许不得转载.https://mp.csdn.net/postedit/82623704 一.Android studio制作计算器源代码这是我学Android ...
基于Android Studio实现的功能强大的购物商城APP源码，可做Android Studio毕业设计、大作业
Android 购物商城app 完整代码下载地址:基于Android Studio实现的功能强大的购物商城APP源码实现的功能: 注册登录修改密码重置密码(邮箱验证,考核结束将移除授权码) 商 ...
Android studio实现计数器功能
Android studio实现计数器功能我们使用原生计时器CountDownTimer 1.首先自己建立一个布局TextView------(countdown我自己定义的名字)可以显示文字 2. ...
Android Studio实现多功能日记本
项目目录一.项目概述二.系统特点三.开发环境四.详细设计 1.E-R图 2.数据库 3.系统设置五.运行演示六.源码获取一.项目概述本次实现了功能实用且齐全的日记本,界面友好,使用便捷 ...
android studio 九宫格,Android Studio 实现九宫格功能
运行结果 1.图 2.动图九个图标是设置的,你也可以设置4 * 4 = 16都可以. 3.分享个GIF动图的.exe 代码activity_main.xml item.xml MainActivit ...
Android studio 简易计算器App的实现及实现加减乘除功能（附完整源码）
在Android studio 实现简易计算器App并实现加减乘除功能结果 activity_main.xml <?xml version="1.0" enco ...
Android studio 实现计算器android 开发小实验
Android 移动开发实现简单计算器功能前言 android 开发小实验 android 移动开发实现简易计算器功能小白也能轻松上手,复制粘贴就可使用使用工具 Android Studio ...

Android Studio实现计算器功能

Android Studio实现计算器功能相关推荐

最新文章

热门文章