Android studio实现简单的计算器

本文实例为大家分享了Android studio实现简单计算器的具体代码,供大家参考,具体内容如下

需求分析及概要设计

目的

开发一个简单的计算器App,使之能够完成加减乘除混合运算

工具及环境

使用java语言,在Android studio平台上进行开发

功能设计

  • “+”:实现两数相加
  • “-”:实现两数相减
  • “*”:实现两数相乘
  • “/”:实现两数相除
  • “=”:计算并得出正确结果
  • “C”:清屏
  • “Backspace”:倒退

设计思路

1、首先设计一个可视化的界面,供用户输入数据并查看结果。

2、用户可通过点击相应按钮输入正确的表达式(注意:这里只实现对正确表达式的计算处理),最后按"="得出正确结果。在计算过程中可以通过点击倒退键修改输入内容,在进行下一次的运算之前必须先进行清零操作。

3、设计好的计算器应可以进行加减乘除混合四则运算,且可以进行小数和整数运算

详细设计

当用户点击按钮时,用SringBuilder变量记录其输入的运算式,并显示到文本区中。

当用户点击"="时,把文本区的运算式拿出来,首先将它内部的一个一个字节拼接成独立的运算数和运算符,然后存储在一个ArrayList数组中,接着再新建两个ArrayList数组,用来分别存放运算数和运算符,然后遍历存储运算式的ArrayList数组,把其中的运算数和运算符分别放进不同的ArrayList中,每一次放置运算符时,都要先和已存在的运算符进行比较,若要放进的运算符优先级低于或等于运算符数组中的运算符,则弹出一个运算符,并从运算数数组中弹出两个运算数,然后进行运算,并把结果送入运算数数组中,直到遇到比自己优先级低的运算符或运算符数组为空时,则送入该运算符。当遍历到运算式末尾时,依次弹出运算符中的运算符,并对应弹出运算数进行运算直到运算符数组为空,此时运算数数组中只有一个数据就是最终的结果

代码

MainAcivity.java

package com.example.qw.calculator;

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

@Override

protected 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() {

@Override

public void onClick(View view) {

result.setSelection(result.getText().length());

}

});

zero.setOnClickListener(new View.OnClickListener() {

@Override

public 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() {

@Override

public 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() {

@Override

public 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() {

@Override

public 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() {

@Override

public 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() {

@Override

public 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() {

@Override

public 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() {

@Override

public 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() {

@Override

public 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() {

@Override

public 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() {

@Override

public void onClick(View v) {

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

calculate_equation.clear();

signal=0;

result.setText("");

}

});

backspace.setOnClickListener(new View.OnClickListener() {

@Override

public 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() {

@Override

public 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() {

@Override

public 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() {

@Override

public 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("+");

}

else

show_equation.append("+");

result.setText(show_equation);

result.setSelection(result.getText().length());

}

}

});

sub.setOnClickListener(new View.OnClickListener() {

@Override

public 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("-");

}

else

show_equation.append("-");

result.setText(show_equation);

result.setSelection(result.getText().length());

}

}

});

mul.setOnClickListener(new View.OnClickListener() {

@Override

public 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("*");

}

else

show_equation.append("*");

result.setText(show_equation);

result.setSelection(result.getText().length());

}

}

});

div.setOnClickListener(new View.OnClickListener() {

@Override

public 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("/");

}

else

show_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;

}

else

return 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();

}

else

break;

}

operator.add(temp4);

}

else

operator.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();

}

}

}

activity_main.xml

<?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">

<EditText

android:id="@+id/result"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:textSize="40sp"

android:enabled="false"/>

<LinearLayout

android:layout_width="match_parent"

android:layout_height="0dp"

android:layout_weight="1"

android:orientation="horizontal">

<Button

android:id="@+id/cls"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="C"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android:id="@+id/div"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="/"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android:id="@+id/mul"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="*"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android: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:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

</LinearLayout>

<LinearLayout

android:layout_width="match_parent"

android:layout_height="0dp"

android:layout_weight="1"

android:orientation="horizontal">

<Button

android:id="@+id/seven"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="7"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android:id="@+id/eight"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="8"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android:id="@+id/nine"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="9"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android:id="@+id/sub"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="-"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

</LinearLayout>

<LinearLayout

android:layout_width="match_parent"

android:layout_height="0dp"

android:layout_weight="1"

android:orientation="horizontal">

<Button

android:id="@+id/four"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="4"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android:id="@+id/five"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="5"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android:id="@+id/six"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="6"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android:id="@+id/add"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="+"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

</LinearLayout>

<LinearLayout

android:layout_width="match_parent"

android:layout_height="0dp"

android:layout_weight="2"

android:orientation="horizontal">

<LinearLayout

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:orientation="vertical">

<LinearLayout

android:layout_width="match_parent"

android:layout_height="1dp"

android:layout_weight="1"

android:orientation="horizontal">

<Button

android:id="@+id/one"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="1"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android:id="@+id/two"

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:textSize="20sp"

android:text="2"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

</LinearLayout>

<LinearLayout

android:layout_width="match_parent"

android:layout_height="1dp"

android:layout_weight="1">

<Button

android:id="@+id/zero"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:text="0"

android:textSize="20sp"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

</LinearLayout>

</LinearLayout>

<LinearLayout

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:orientation="horizontal">

<LinearLayout

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1"

android:orientation="vertical">

<Button

android:id="@+id/three"

android:layout_width="match_parent"

android:layout_height="1dp"

android:layout_weight="1"

android:text="3"

android:textSize="20sp"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

<Button

android:id="@+id/spot"

android:layout_width="match_parent"

android:layout_height="1dp"

android:layout_weight="1"

android:text="."

android:textSize="20sp"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

</LinearLayout>

<LinearLayout

android:layout_width="0dp"

android:layout_height="match_parent"

android:layout_weight="1">

<Button

android:id="@+id/equal"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:text="="

android:textSize="20sp"

android:background="@drawable/buttonstytle"

android:textColor="#ffffff"/>

</LinearLayout>

</LinearLayout>

</LinearLayout>

</LinearLayout>

buttonstytle.xml

<?xml version="1.0" encoding="utf-8"?>

<shape xmlns:android="http://schemas.android.com/apk/res/android" >

<!-- 主体背景颜色值 -->

<solid android:color="#666666" />

<!-- 连框宽度和颜色值 -->

<stroke

android:width="0.01dp"

android:color="#FFFFFF" />

</shape>

####结果分析

启动计算器并输入运算式“59.0-8/46+2”如下图:

结果如下图:

总结

这次做计算器收获很大,首先我对Android studio中的布局有了更深刻的认识,其次在这次编程中熟悉了怎么设置断点调试以快速的找出问题所在。当然,这次的作品也是不够成熟的,因为没有做有关错误表达式的相应处理,因为时间和精力有限,这次只能先做这么多了

注: 今天没事又看了一下这个代码,发现问题很多,简直是惨不忍睹(希望没坑到你们)。比如直接按加、减、乘、除和等号键及后退键会闪退,刚开始一直按 “0” 可以一直输入0,同一个数中可以输入多个小数点等等,我感到很惭愧哈,本人能力有限,不过还是抽时间又改了一下,修复了这些bug,另外也优化了一些东西,上面贴的代码我已经更新了,GitHub上的源码我很快也会更新的,哪里做的不好也希望大家不吝赐教哈 -2018/11/5

链接:源代码下载地址

更多计算器功能实现,请点击专题: 计算器功能汇总 进行学习

关于Android计算器功能的实现,查看专题:Android计算器 进行学习。

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。

以上是 Android studio实现简单的计算器 的全部内容, 来源链接: utcz.com/p/242606.html

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