本文实例为大家分享了Android实现横屏切换科学计算器的具体代码，供大家参考，具体内容如下
简单计算器设计，实现以下功能：
1、竖屏时能实现基本的加减乘除运算、回退和清空输入。
2、横屏时变为科学计算器，实现函数计算、进制换算等功能。输入计算公式，按等号键输出计算结果。
3、公式输入和结果显示区支持长按弹出复制、粘贴功能。
4、使用计算器过程中应不弹出软键盘。
5、可以通过进度条实时调整计算结果保留的小数点后位数，或者通过音量键完成同样的效果。
6、实现附加功能：三角函数、阶乘、XY、八进制转换、十六进制转换、√(Y&X)及括号，如sin(90)。
竖屏简单计算器
竖屏界面设计xml代码：
竖屏效果图：（调节进度条或通过音量键可以调节小数点位数唷！）
横屏xml代码：
横屏效果图：
Java代码如下：
package com.zjw;
import android.app.Activity;
import android.content.ClipboardManager;
import android.content.res.Configuration;
import android.graphics.Point;
import android.os.Bundle;
import android.text.Editable;
import android.text.method.KeyListener;
import android.util.Log;
import android.view.Display;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.SeekBar;
import android.widget.TextView;
import android.widget.Toast;
import androidx.annotation.NonNull;
import java.math.BigDecimal;
import java.util.StringTokenizer;
public class MainActivity extends Activity {
/**
* 定义变量
*/
//舍入精度
public static final int[] DEF_DIV_SCALE = {17};
//初始化显示数据
private final String[] init =new String[1];
//显示框
private EditText input;// 用于显示输出结果
//划动条
private SeekBar seekBar;
//普通控件及变量
private Button[] btn = new Button[10];// 0~9十个数字
private TextView mem, _drg, tip;
private Button div, mul, sub, add, equal, sin, cos, tan, log, ln, sqrt,
square, factorial, bksp, left, right, dot, bd, db, drg, mc, c;
public String str_old;
public String str_new;
public boolean vbegin = true;// 控制输入，true为重新输入，false为接着输入
public boolean drg_flag = true;// true为角度，false为弧度
public double pi = 4 * Math.atan(1);// π值
public boolean tip_lock = true;// true为正确，可以继续输入，false错误，输入锁定
public boolean equals_flag = true;// 是否在按下=之后输入，true为之前，false为之后
//定义ContextMenu中每个菜单选项的Id
final int Menu_1 = Menu.FIRST;
final int Menu_2 = Menu.FIRST + 1;
private ClipboardManager mClipboard = null;
public boolean onCreateOptionsMenu(Menu menu) {
//导入菜单布局
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public boolean onOptionsItemSelected(MenuItem item) {
//创建菜单项的点击事件
switch (item.getItemId()) {
case R.id.menu_setting:
Toast.makeText(this, "点击了设置", Toast.LENGTH_SHORT).show();
break;
case R.id.menu_out:
// Toast.makeText(this, "点击了退出", Toast.LENGTH_SHORT).show();
android.os.Process.killProcess(android.os.Process.myPid());//获取PID
System.exit(0);
break;
default:
break;
}
return super.onOptionsItemSelected(item);
}
/**
*onCreate
*/
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//切换布局后调用，初始化显示
if(savedInstanceState!=null){
init[0] = savedInstanceState.getString("exp");
equals_flag = false;
}
//屏幕方向监听
int orientation = getResources().getConfiguration().orientation;
if (orientation == Configuration.ORIENTATION_LANDSCAPE) {
// 横屏内容
setContentView(R.layout.activity_main2);
InitWigdet();
AllWigdetListener();
}
else if (orientation == Configuration.ORIENTATION_PORTRAIT) {
// 竖屏内容
setContentView(R.layout.activity_main);
input = (EditText)findViewById(R.id.textView);
input.setText(init[0]);
seekBar = (SeekBar) findViewById(R.id.seekBar);
seekBar.setProgress(DEF_DIV_SCALE[0]);
seekBar.setOnSeekBarChangeListener(onSeekBarChangeListener);
Display defaultDisplay = getWindowManager().getDefaultDisplay();
Point point = new Point();
defaultDisplay.getSize(point);
Integer x = point.x;
Integer y = point.y;
input.setKeyListener(new KeyListener() {
@Override
public int getInputType() {
return 0;
}
@Override
public boolean onKeyDown(View view, Editable editable, int i, KeyEvent keyEvent) {
return false;
}
@Override
public boolean onKeyUp(View view, Editable editable, int i, KeyEvent keyEvent) {
return false;
}
@Override
public boolean onKeyOther(View view, Editable editable, KeyEvent keyEvent) {
return false;
}
@Override
public void clearMetaKeyState(View view, Editable editable, int i) {
}
});
View.OnClickListener onClearListener = new View.OnClickListener() {
@Override
public void onClick(View view) {
input.setText("");
}
};
View.OnClickListener onClearLastListener = new View.OnClickListener() {
@Override
public void onClick(View view) {
String s = input.getText().toString();
int len = s.length();
if(len>0) {
s = s.substring(0, len - 1);
input.setText(s);
}
}
};
View.OnClickListener onEXPListener = new View.OnClickListener() {
@Override
public void onClick(View view) {
Button temp = (Button)view;
String s = temp.getText().toString();
String show = input.getText().toString();
int len = show.length();
if(show.length()==0){
if(s.equals("+")||s.equals("×")||s.equals("÷")) return;
}
if((show.endsWith("+"))||(show.endsWith("-"))||(show.endsWith("×"))||(show.endsWith("÷"))||(show.endsWith("."))){
if(s.equals("+")||s.equals("×")||s.equals("÷")||s.equals("-")||(s.equals("."))){
show = show.substring(0,len-1) + s;
input.setText(show);
}else{
input.append(s);
}
}else{
input.append(s);
}
}
};
View.OnClickListener onEXECListener = new View.OnClickListener() {
@Override
public void onClick(View view) {
String s = input.getText().toString();
if(s.length()==0) return;
s = s.replace("×","*");
s = s.replace("÷","/");
s = s.replace("%","");
if((s.endsWith("+"))||(s.endsWith("-"))||(s.endsWith("*"))||(s.endsWith("/"))||(s.endsWith(".")))return;
try{
String re = Calculator.conversion(s);
re = round(re,DEF_DIV_SCALE[0]);
if(re.indexOf(".") > 0){
re = re.replaceAll("0+?$", "");//去掉多余的0
re = re.replaceAll("[.]$", "");//如最后一位是.则去掉
}
input.setText(re);
}catch (Exception e){
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
input.setText("");
}
}
};
View.OnClickListener onPERCENTCListener = new View.OnClickListener() {
@Override
public void onClick(View view) {
String s = input.getText().toString();
if(s.length()==0) return;
s = s.replace("×","*");
s = s.replace("÷","/");
s = s.replace("%","");
if((s.endsWith("+"))||(s.endsWith("-"))||(s.endsWith("*"))||(s.endsWith("/"))||(s.endsWith("."))) return;
s = s+"/100";
try{
String re = Calculator.conversion(s);
re = round(re,DEF_DIV_SCALE[0]);
if(re.indexOf(".") > 0){
re = re.replaceAll("0+?$", "");//去掉多余的0
re = re.replaceAll("[.]$", "");//如最后一位是.则去掉
}
input.setText(re+"%");
}catch (Exception e){
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
input.setText("");
}
}
};
input.getLayoutParams().height = 2*y/7;
Button button5 = (Button)findViewById(R.id.button5); button5.getLayoutParams().width = x/4 ;button5.getLayoutParams().height = y/8;
Button button6 = (Button)findViewById(R.id.button6); button6.getLayoutParams().width = x/4 ;button6.getLayoutParams().height = y/8;
Button button7 = (Button)findViewById(R.id.button7); button7.getLayoutParams().width = x/4 ;button7.getLayoutParams().height = y/8;
Button button8 = (Button)findViewById(R.id.button8); button8.getLayoutParams().width = x/4 ;button8.getLayoutParams().height = y/8;
Button button9 = (Button)findViewById(R.id.button9); button9.getLayoutParams().width = x/4 ;button9.getLayoutParams().height = y/8;
Button button10 = (Button)findViewById(R.id.button10); button10.getLayoutParams().width = x/4 ;button10.getLayoutParams().height = y/8;
Button button11 = (Button)findViewById(R.id.button11); button11.getLayoutParams().width = x/4 ;button11.getLayoutParams().height = y/8;
Button button12 = (Button)findViewById(R.id.button12); button12.getLayoutParams().width = x/4 ;button12.getLayoutParams().height = y/8;
Button button13 = (Button)findViewById(R.id.button13); button13.getLayoutParams().width = x/4 ;button13.getLayoutParams().height = y/8;
Button button14 = (Button)findViewById(R.id.button14); button14.getLayoutParams().width = x/4 ;button14.getLayoutParams().height = y/8;
Button button15 = (Button)findViewById(R.id.button15); button15.getLayoutParams().width = x/4 ;button15.getLayoutParams().height = y/8;
Button button16 = (Button)findViewById(R.id.button16); button16.getLayoutParams().width = x/4 ;button16.getLayoutParams().height = y/8;
Button button17 = (Button)findViewById(R.id.button17); button17.getLayoutParams().width = x/4 ;button17.getLayoutParams().height = y/8;
Button button18 = (Button)findViewById(R.id.button18); button18.getLayoutParams().width = x/4 ;button18.getLayoutParams().height = y/8;
Button button19 = (Button)findViewById(R.id.button19); button19.getLayoutParams().width = x/4 ;button19.getLayoutParams().height = y/8;
Button button20 = (Button)findViewById(R.id.button20); button20.getLayoutParams().width = x/4 ;button20.getLayoutParams().height = 2*(y/8);
Button button21 = (Button)findViewById(R.id.button21); button21.getLayoutParams().width = x/4 ;button21.getLayoutParams().height = y/8;
Button button22 = (Button)findViewById(R.id.button22); button22.getLayoutParams().width = x/4 ;button22.getLayoutParams().height = y/8;
Button button23 = (Button)findViewById(R.id.button23); button23.getLayoutParams().width = x/4 ;button23.getLayoutParams().height = y/8;
button6.setOnClickListener(onEXPListener);button7.setOnClickListener(onEXPListener);
button9.setOnClickListener(onEXPListener);button10.setOnClickListener(onEXPListener);
button11.setOnClickListener(onEXPListener);button12.setOnClickListener(onEXPListener);
button13.setOnClickListener(onEXPListener);button14.setOnClickListener(onEXPListener);
button15.setOnClickListener(onEXPListener);button16.setOnClickListener(onEXPListener);
button17.setOnClickListener(onEXPListener);button18.setOnClickListener(onEXPListener);
button19.setOnClickListener(onEXPListener);button21.setOnClickListener(onEXPListener);
button22.setOnClickListener(onEXPListener);button23.setOnClickListener(onEXPListener);
button5.setOnClickListener(onClearListener);
button8.setOnClickListener(onClearLastListener);
button20.setOnClickListener(onEXECListener);
button21.setOnClickListener(onPERCENTCListener);
}
}
/**
* 初始化所有的组件
*/
private void InitWigdet() {
//获取屏幕参数
Display defaultDisplay = getWindowManager().getDefaultDisplay();
Point point = new Point();
defaultDisplay.getSize(point);
Integer x = point.x;
Integer y = point.y - 60;
// 获取界面元素
input = (EditText) findViewById(R.id.input);
input.setKeyListener(new KeyListener() {
@Override
public int getInputType() {
return 0;
}
@Override
public boolean onKeyDown(View view, Editable editable, int i, KeyEvent keyEvent) {
return false;
}
@Override
public boolean onKeyUp(View view, Editable editable, int i, KeyEvent keyEvent) {
return false;
}
@Override
public boolean onKeyOther(View view, Editable editable, KeyEvent keyEvent) {
return false;
}
@Override
public void clearMetaKeyState(View view, Editable editable, int i) {
}
});
input.setText(init[0]);
seekBar = (SeekBar) findViewById(R.id.seekBar); //seekBar.getLayoutParams().height = y/7/3;
seekBar.setProgress(DEF_DIV_SCALE[0]);
seekBar.setOnSeekBarChangeListener(onSeekBarChangeListener);
input.getLayoutParams().height = y/9;
mem = (TextView) findViewById(R.id.mem);
tip = (TextView) findViewById(R.id.tip);
_drg = (TextView) findViewById(R.id._drg); _drg.getLayoutParams().width = x/6 ;_drg.getLayoutParams().height = y/10-8;
btn[0] = (Button) findViewById(R.id.zero); btn[0].getLayoutParams().width = x/6 ;btn[0].getLayoutParams().height = y/10;
btn[1] = (Button) findViewById(R.id.one); btn[1].getLayoutParams().width = x/6 ;btn[1].getLayoutParams().height = y/10;
btn[2] = (Button) findViewById(R.id.two); btn[2].getLayoutParams().width = x/6 ;btn[2].getLayoutParams().height = y/10;
btn[3] = (Button) findViewById(R.id.three); btn[3].getLayoutParams().width = x/6 ;btn[3].getLayoutParams().height = y/10;
btn[4] = (Button) findViewById(R.id.four); btn[4].getLayoutParams().width = x/6 ;btn[4].getLayoutParams().height = y/10;
btn[5] = (Button) findViewById(R.id.five); btn[5].getLayoutParams().width = x/6 ;btn[5].getLayoutParams().height = y/10;
btn[6] = (Button) findViewById(R.id.six); btn[6].getLayoutParams().width = x/6 ;btn[6].getLayoutParams().height = y/10;
btn[7] = (Button) findViewById(R.id.seven); btn[7].getLayoutParams().width = x/6 ;btn[7].getLayoutParams().height = y/10;
btn[8] = (Button) findViewById(R.id.eight); btn[8].getLayoutParams().width = x/6 ;btn[8].getLayoutParams().height = y/10;
btn[9] = (Button) findViewById(R.id.nine); btn[9].getLayoutParams().width = x/6 ;btn[9].getLayoutParams().height = y/10;
div = (Button) findViewById(R.id.divide); div.getLayoutParams().width = x/6 ;div.getLayoutParams().height = y/10;
mul = (Button) findViewById(R.id.mul);mul.getLayoutParams().width = x/6 ;mul.getLayoutParams().height = y/10;
sub = (Button) findViewById(R.id.sub); sub.getLayoutParams().width = x/6 ;sub.getLayoutParams().height = y/10;
add = (Button) findViewById(R.id.add); add.getLayoutParams().width = x/6 ;add.getLayoutParams().height = y/10;
equal = (Button) findViewById(R.id.equal); equal.getLayoutParams().width = 2*x/6 ;equal.getLayoutParams().height = y/10;
sin = (Button) findViewById(R.id.sin); sin.getLayoutParams().width = x/6 ;sin.getLayoutParams().height = y/10-8;
cos = (Button) findViewById(R.id.cos); cos.getLayoutParams().width = x/6 ;cos.getLayoutParams().height = y/10-8;
tan = (Button) findViewById(R.id.tan); tan.getLayoutParams().width = x/6 ;tan.getLayoutParams().height = y/10-8;
log = (Button) findViewById(R.id.log); log.getLayoutParams().width = x/6 ;log.getLayoutParams().height = y/10;
ln = (Button) findViewById(R.id.ln); ln.getLayoutParams().width = x/6 ;ln.getLayoutParams().height = y/10;
sqrt = (Button) findViewById(R.id.sqrt); sqrt.getLayoutParams().width = x/6 ;sqrt.getLayoutParams().height = y/10;
square = (Button) findViewById(R.id.square); square.getLayoutParams().width = x/6 ;square.getLayoutParams().height = y/10;
factorial = (Button) findViewById(R.id.factorial);factorial.getLayoutParams().width = x/6 ;factorial.getLayoutParams().height = y/10-8;
bksp = (Button) findViewById(R.id.bksp);bksp.getLayoutParams().width = 2*x/6 ;bksp.getLayoutParams().height = y/10-8;
left = (Button) findViewById(R.id.left); left.getLayoutParams().width = x/6 ;left.getLayoutParams().height = y/10;
right = (Button) findViewById(R.id.right); right.getLayoutParams().width = x/6 ;right.getLayoutParams().height = y/10;
dot = (Button) findViewById(R.id.dot);dot.getLayoutParams().width = x/6 ;dot.getLayoutParams().height = y/10;
bd = (Button) findViewById(R.id.bd);
LinearLayout linearLayout = (LinearLayout) findViewById(R.id.linear);linearLayout.getLayoutParams().width = x/6 ;linearLayout.getLayoutParams().height = y/10;
db = (Button) findViewById(R.id.db);
drg = (Button) findViewById(R.id.drg);drg.getLayoutParams().width = x/6 ;drg.getLayoutParams().height = y/10-8;
mc = (Button) findViewById(R.id.mc); mc.getLayoutParams().width = 2*x/6 ;mc.getLayoutParams().height = y/10-8;
c = (Button) findViewById(R.id.c); c.getLayoutParams().width = 2*x/6 ;c.getLayoutParams().height = y/10-8;
}
/**
* 为所有按键绑定监听器
*/
private void AllWigdetListener() {
// 数字键
for (int i = 0; i < 10; i++) {
btn[i].setOnClickListener(actionPerformed);
}
// 为+-x÷等按键绑定监听器
div.setOnClickListener(actionPerformed);
mul.setOnClickListener(actionPerformed);
sub.setOnClickListener(actionPerformed);
add.setOnClickListener(actionPerformed);
equal.setOnClickListener(actionPerformed);
sin.setOnClickListener(actionPerformed);
cos.setOnClickListener(actionPerformed);
tan.setOnClickListener(actionPerformed);
log.setOnClickListener(actionPerformed);
ln.setOnClickListener(actionPerformed);
sqrt.setOnClickListener(actionPerformed);
square.setOnClickListener(actionPerformed);
factorial.setOnClickListener(actionPerformed);
bksp.setOnClickListener(actionPerformed);
left.setOnClickListener(actionPerformed);
right.setOnClickListener(actionPerformed);
dot.setOnClickListener(actionPerformed);
bd.setOnClickListener(actionPerformed);
db.setOnClickListener(actionPerformed);
drg.setOnClickListener(actionPerformed);
mc.setOnClickListener(actionPerformed);
c.setOnClickListener(actionPerformed);
}
/**
* 键盘命令捕捉
*/
String[] TipCommand = new String[500];
int tip_i = 0;// TipCommand的指针
private View.OnClickListener actionPerformed = new View.OnClickListener() {
public void onClick(View v) {
// 按键上的命令获取
String command = ((Button) v).getText().toString();
// 显示器上的字符串
String str = input.getText().toString();
// 检测输入是否合法
if (equals_flag == false
&& "0123456789.()sincostanlnlogn!+-×÷√^".indexOf(command) != -1) {
// 检测显示器上的字符串是否合法
if (right(str)) {
if ("+-×÷√^)".indexOf(command) != -1) {
for (int i = 0; i < str.length(); i++) {
TipCommand[tip_i] = String.valueOf(str.charAt(i));
tip_i++;
}
vbegin = false;
}
} else {
input.setText("0");
vbegin = true;
tip_i = 0;
tip_lock = true;
tip.setText("welcome use the APP！");
}
equals_flag = true;
}
if (tip_i > 0)
TipChecker(TipCommand[tip_i - 1], command);
else if (tip_i == 0) {
TipChecker("#", command);
}
if ("0123456789.()sincostanlnlogn!+-×÷√^".indexOf(command) != -1
&& tip_lock) {
TipCommand[tip_i] = command;
tip_i++;
}
// 若输入正确，则将输入信息显示到显示器上
if ("0123456789.()sincostanlnlogn!+-×÷√^".indexOf(command) != -1
&& tip_lock) { // 共25个按键
print(command);
// 若果点击了“DRG”，则切换当前弧度角度制，并将切换后的结果显示到按键上方。
} else if (command.compareTo("DRG") == 0 && tip_lock) {
if (drg_flag == true) {
drg_flag = false;
_drg.setText("RAD");
} else {
drg_flag = true;
_drg.setText("DEG");
}
// 如果输入时退格键，并且是在按=之前
} else if (command.compareTo("◁") == 0 && equals_flag) {
// 一次删除3个字符
if (TTO(str) == 3) {
if (str.length() > 3)
input.setText(str.substring(0, str.length() - 3));
else if (str.length() == 3) {
input.setText("0");
vbegin = true;
tip_i = 0;
tip.setText("welcome use the APP！");
}
// 依次删除2个字符
} else if (TTO(str) == 2) {
if (str.length() > 2)
input.setText(str.substring(0, str.length() - 2));
else if (str.length() == 2) {
input.setText("0");
vbegin = true;
tip_i = 0;
tip.setText("welcome use the APP！");
}
// 依次删除一个字符
} else if (TTO(str) == 1) {
// 若之前输入的字符串合法则删除一个字符
if (right(str)) {
if (str.length() > 1)
input.setText(str.substring(0, str.length() - 1));
else if (str.length() == 1) {
input.setText("0");
vbegin = true;
tip_i = 0;
tip.setText("welcome use the APP！");
}
// 若之前输入的字符串不合法则删除全部字符
} else {
input.setText("0");
vbegin = true;
tip_i = 0;
tip.setText("welcome use the APP！");
}
}
if (input.getText().toString().compareTo("-") == 0
|| equals_flag == false) {
input.setText("0");
vbegin = true;
tip_i = 0;
tip.setText("welcome use the APP！");
}
tip_lock = true;
if (tip_i > 0)
tip_i--;
// 如果是在按=之后输入退格键
} else if (command.compareTo("Bksp") == 0 && equals_flag == false) {
// 将显示器内容设置为0
input.setText("0");
vbegin = true;
tip_i = 0;
tip_lock = true;
tip.setText("welcome use the APP！");
// 如果输入的是清除键
} else if (command.compareTo("C") == 0) {
// 将显示器内容设置为0
input.setText("0");
// 重新输入标志置为true
vbegin = true;
// 缓存命令位数清0
tip_i = 0;
// 表明可以继续输入
tip_lock = true;
// 表明输入=之前
equals_flag = true;
tip.setText("welcome use the APP！");
// 如果输入的是”MC“，则将存储器内容清0
} else if (command.compareTo("MC") == 0) {
mem.setText("0");
// 如果按”bd“则转换进制
} else if (command.compareTo("B") == 0) {
String s = input.getText().toString();
s = s.replace(".","");
//非法字符清屏
if(".+-x÷√^sincostanloglnn!()".indexOf(s) != -1){
input.setText("0");
}else
{
try {
int a = Integer.valueOf(s);
String re = Integer.toBinaryString(a);
input.setText(re);
}catch (Exception e){
input.setText("");
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
}
}
// 如果按”db“则转换进制
}else if(command.compareTo("D") == 0){
String s = input.getText().toString();
s = s.replace(".","");
input.setText("1234567890");
//非法字符清屏
if("23456789+-x÷√^sincostanloglnn!().".indexOf(s) != -1){
input.setText("0");
}else{
try{
Integer re = Integer.parseInt(s,2);
input.setText(re.toString());
}catch (Exception e){
input.setText("");
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
}
}
} else if (command.compareTo("=") == 0 && tip_lock && right(str)
&& equals_flag) {
tip_i = 0;
// 表明不可以继续输入
tip_lock = false;
// 表明输入=之后
equals_flag = false;
// 保存原来算式样子
str_old = str;
// 替换算式中的运算符，便于计算
str = str.replaceAll("sin", "s");
str = str.replaceAll("cos", "c");
str = str.replaceAll("tan", "t");
str = str.replaceAll("log", "g");
str = str.replaceAll("ln", "l");
str = str.replaceAll("n!", "!");
// 重新输入标志设置true
vbegin = true;
// 将-1x转换成-
str_new = str.replaceAll("-", "-1×");
// 计算算式结果
new calc().process(str_new);
}
// 表明可以继续输入
tip_lock = true;
}
};
/*
* 检测函数，对str进行前后语法检测 为Tip的提示方式提供依据，与TipShow()配合使用 编号 字符 其后可以跟随的合法字符 1 （
* 数字|（|-|.|函数 2 ） 算符|）|√ ^ 3 . 数字|算符|）|√ ^ 4 数字 .|数字|算符|）|√ ^ 5 算符
* 数字|（|.|函数 6 √ ^ （ |. | 数字 7 函数 数字|（|.
*
* 小数点前后均可省略，表示0 数字第一位可以为0
*/
private void TipChecker(String tipcommand1, String tipcommand2) {
// Tipcode1表示错误类型，Tipcode2表示名词解释类型
int Tipcode1 = 0, Tipcode2 = 0;
// 表示命令类型
int tiptype1 = 0, tiptype2 = 0;
// 括号数
int bracket = 0;
// “+-x÷√^”不能作为第一位
if (tipcommand1.compareTo("#") == 0
&& (tipcommand2.compareTo("÷") == 0
|| tipcommand2.compareTo("×") == 0
|| tipcommand2.compareTo("+") == 0
|| tipcommand2.compareTo(")") == 0
|| tipcommand2.compareTo("√") == 0 || tipcommand2
.compareTo("^") == 0)) {
Tipcode1 = -1;
}
// 定义存储字符串中最后一位的类型
else if (tipcommand1.compareTo("#") != 0) {
if (tipcommand1.compareTo("(") == 0) {
tiptype1 = 1;
} else if (tipcommand1.compareTo(")") == 0) {
tiptype1 = 2;
} else if (tipcommand1.compareTo(".") == 0) {
tiptype1 = 3;
} else if ("0123456789".indexOf(tipcommand1) != -1) {
tiptype1 = 4;
} else if ("+-×÷".indexOf(tipcommand1) != -1) {
tiptype1 = 5;
} else if ("√^".indexOf(tipcommand1) != -1) {
tiptype1 = 6;
} else if ("sincostanloglnn!".indexOf(tipcommand1) != -1) {
tiptype1 = 7;
}
// 定义欲输入的按键类型
if (tipcommand2.compareTo("(") == 0) {
tiptype2 = 1;
} else if (tipcommand2.compareTo(")") == 0) {
tiptype2 = 2;
} else if (tipcommand2.compareTo(".") == 0) {
tiptype2 = 3;
} else if ("0123456789".indexOf(tipcommand2) != -1) {
tiptype2 = 4;
} else if ("+-×÷".indexOf(tipcommand2) != -1) {
tiptype2 = 5;
} else if ("√^".indexOf(tipcommand2) != -1) {
tiptype2 = 6;
} else if ("sincostanloglnn!".indexOf(tipcommand2) != -1) {
tiptype2 = 7;
}
switch (tiptype1) {
case 1:
// 左括号后面直接接右括号,“+x÷”（负号“-”不算）,或者"√^"
if (tiptype2 == 2
|| (tiptype2 == 5 && tipcommand2.compareTo("-") != 0)
|| tiptype2 == 6)
Tipcode1 = 1;
break;
case 2:
// 右括号后面接左括号，数字，“+-x÷sin^...”
if (tiptype2 == 1 || tiptype2 == 3 || tiptype2 == 4
|| tiptype2 == 7)
Tipcode1 = 2;
break;
case 3:
// “.”后面接左括号或者“sincos...”
if (tiptype2 == 1 || tiptype2 == 7)
Tipcode1 = 3;
// 连续输入两个“.”
if (tiptype2 == 3)
Tipcode1 = 8;
break;
case 4:
// 数字后面直接接左括号或者“sincos...”
if (tiptype2 == 1 || tiptype2 == 7)
Tipcode1 = 4;
break;
case 5:
// “+-x÷”后面直接接右括号，“+-x÷√^”
if (tiptype2 == 2 || tiptype2 == 5 || tiptype2 == 6)
Tipcode1 = 5;
break;
case 6:
// “√^”后面直接接右括号，“+-x÷√^”以及“sincos...”
if (tiptype2 == 2 || tiptype2 == 5 || tiptype2 == 6
|| tiptype2 == 7)
Tipcode1 = 6;
break;
case 7:
// “sincos...”后面直接接右括号“+-x÷√^”以及“sincos...”
if (tiptype2 == 2 || tiptype2 == 5 || tiptype2 == 6
|| tiptype2 == 7)
Tipcode1 = 7;
break;
}
}
// 检测小数点的重复性，Tipconde1=0,表明满足前面的规则
if (Tipcode1 == 0 && tipcommand2.compareTo(".") == 0) {
int tip_point = 0;
for (int i = 0; i < tip_i; i++) {
// 若之前出现一个小数点点，则小数点计数加1
if (TipCommand[i].compareTo(".") == 0) {
tip_point++;
}
// 若出现以下几个运算符之一，小数点计数清零
if (TipCommand[i].compareTo("sin") == 0
|| TipCommand[i].compareTo("cos") == 0
|| TipCommand[i].compareTo("tan") == 0
|| TipCommand[i].compareTo("log") == 0
|| TipCommand[i].compareTo("ln") == 0
|| TipCommand[i].compareTo("n!") == 0
|| TipCommand[i].compareTo("√") == 0
|| TipCommand[i].compareTo("^") == 0
|| TipCommand[i].compareTo("÷") == 0
|| TipCommand[i].compareTo("×") == 0
|| TipCommand[i].compareTo("-") == 0
|| TipCommand[i].compareTo("+") == 0
|| TipCommand[i].compareTo("(") == 0
|| TipCommand[i].compareTo(")") == 0) {
tip_point = 0;
}
}
tip_point++;
// 若小数点计数大于1，表明小数点重复了
if (tip_point > 1) {
Tipcode1 = 8;
}
}
// 检测右括号是否匹配
if (Tipcode1 == 0 && tipcommand2.compareTo(")") == 0) {
int tip_right_bracket = 0;
for (int i = 0; i < tip_i; i++) {
// 如果出现一个左括号，则计数加1
if (TipCommand[i].compareTo("(") == 0) {
tip_right_bracket++;
}
// 如果出现一个右括号，则计数减1
if (TipCommand[i].compareTo(")") == 0) {
tip_right_bracket--;
}
}
// 如果右括号计数=0,表明没有响应的左括号与当前右括号匹配
if (tip_right_bracket == 0) {
Tipcode1 = 10;
}
}
// 检查输入=的合法性
if (Tipcode1 == 0 && tipcommand2.compareTo("=") == 0) {
// 括号匹配数
int tip_bracket = 0;
for (int i = 0; i < tip_i; i++) {
if (TipCommand[i].compareTo("(") == 0) {
tip_bracket++;
}
if (TipCommand[i].compareTo(")") == 0) {
tip_bracket--;
}
}
// 若大于0，表明左括号还有未匹配的
if (tip_bracket > 0) {
Tipcode1 = 9;
bracket = tip_bracket;
} else if (tip_bracket == 0) {
// 若前一个字符是以下之一，表明=号不合法
if ("√^sincostanloglnn!".indexOf(tipcommand1) != -1) {
Tipcode1 = 6;
}
// 若前一个字符是以下之一，表明=号不合法
if ("+-×÷".indexOf(tipcommand1) != -1) {
Tipcode1 = 5;
}
}
}
// 若命令式以下之一，则显示相应的帮助信息
if (tipcommand2.compareTo("MC") == 0)
Tipcode2 = 1;
if (tipcommand2.compareTo("C") == 0)
Tipcode2 = 2;
if (tipcommand2.compareTo("DRG") == 0)
Tipcode2 = 3;
if (tipcommand2.compareTo("Bksp") == 0)
Tipcode2 = 4;
if (tipcommand2.compareTo("sin") == 0)
Tipcode2 = 5;
if (tipcommand2.compareTo("cos") == 0)
Tipcode2 = 6;
if (tipcommand2.compareTo("tan") == 0)
Tipcode2 = 7;
if (tipcommand2.compareTo("log") == 0)
Tipcode2 = 8;
if (tipcommand2.compareTo("ln") == 0)
Tipcode2 = 9;
if (tipcommand2.compareTo("n!") == 0)
Tipcode2 = 10;
if (tipcommand2.compareTo("√") == 0)
Tipcode2 = 11;
if (tipcommand2.compareTo("^") == 0)
Tipcode2 = 12;
// 显示帮助和错误信息
TipShow(bracket, Tipcode1, Tipcode2, tipcommand1, tipcommand2);
}
/*
* 反馈Tip信息，加强人机交互，与TipChecker()配合使用
*/
private void TipShow(int bracket, int tipcode1, int tipcode2,String tipcommand1, String tipcommand2) {
String tipmessage = "";
if (tipcode1 != 0)
tip_lock = false;// 表明输入有误
switch (tipcode1) {
case -1:
tipmessage = tipcommand2 + " 不能作为第一个算符\n";
break;
case 1:
tipmessage = tipcommand1 + " 后应输入：数字/(/./-/函数 \n";
break;
case 2:
tipmessage = tipcommand1 + " 后应输入：)/算符 \n";
break;
case 3:
tipmessage = tipcommand1 + " 后应输入：)/数字/算符 \n";
break;
case 4:
tipmessage = tipcommand1 + " 后应输入：)/./数字 /算符 \n";
break;
case 5:
tipmessage = tipcommand1 + " 后应输入：(/./数字/函数 \n";
break;
case 6:
tipmessage = tipcommand1 + " 后应输入：(/./数字 \n";
break;
case 7:
tipmessage = tipcommand1 + " 后应输入：(/./数字 \n";
break;
case 8:
tipmessage = "小数点重复\n";
break;
case 9:
tipmessage = "不能计算，缺少 " + bracket + " 个 )";
break;
case 10:
tipmessage = "不需要 )";
break;
}
switch (tipcode2) {
case 1:
tipmessage = tipmessage + "[MC 用法: 清除记忆 MEM]";
break;
case 2:
tipmessage = tipmessage + "[C 用法: 归零]";
break;
case 3:
tipmessage = tipmessage + "[DRG 用法: 选择 DEG 或 RAD]";
break;
case 4:
tipmessage = tipmessage + "[Bksp 用法: 退格]";
break;
case 5:
tipmessage = tipmessage + "sin 函数用法示例：\n"
+ "DEG：sin30 = 0.5 RAD：sin1 = 0.84\n"
+ "注：与其他函数一起使用时要加括号，如：\n" + "sin(cos45)，而不是sincos45";
break;
case 6:
tipmessage = tipmessage + "cos 函数用法示例：\n"
+ "DEG：cos60 = 0.5 RAD：cos1 = 0.54\n"
+ "注：与其他函数一起使用时要加括号，如：\n" + "cos(sin45)，而不是cossin45";
break;
case 7:
tipmessage = tipmessage + "tan 函数用法示例：\n"
+ "DEG：tan45 = 1 RAD：tan1 = 1.55\n"
+ "注：与其他函数一起使用时要加括号，如：\n" + "tan(cos45)，而不是tancos45";
break;
case 8:
tipmessage = tipmessage + "log 函数用法示例：\n"
+ "log10 = log(5+5) = 1\n" + "注：与其他函数一起使用时要加括号，如：\n"
+ "log(tan45)，而不是logtan45";
break;
case 9:
tipmessage = tipmessage + "ln 函数用法示例：\n"
+ "ln10 = le(5+5) = 2.3 lne = 1\n"
+ "注：与其他函数一起使用时要加括号，如：\n" + "ln(tan45)，而不是lntan45";
break;
case 10:
tipmessage = tipmessage + "n! 函数用法示例：\n"
+ "n!3 = n!(1+2) = 3×2×1 = 6\n" + "注：与其他函数一起使用时要加括号，如：\n"
+ "n!(log1000)，而不是n!log1000";
break;
case 11:
tipmessage = tipmessage + "√ 用法示例：开任意次根号\n"
+ "如：27开3次根为 27√3 = 3\n" + "注：与其他函数一起使用时要加括号，如：\n"
+ "(函数)√(函数) ， (n!3)√(log100) = 2.45";
break;
case 12:
tipmessage = tipmessage + "^ 用法示例：开任意次平方\n" + "如：2的3次方为 2^3 = 8\n"
+ "注：与其他函数一起使用时要加括号，如：\n"
+ "(函数)√(函数) ， (n!3)^(log100) = 36";
break;
}
// 将提示信息显示到tip
tip.setText(tipmessage);
}
/**
* 将信息显示在显示屏上
*/
private void print(String str) {
// 清屏后输出
if (vbegin) {
input.setText(str);
} else {
input.append(str);
}
vbegin = false;
}
/*
* 检测函数，返回值为3、2、1 表示应当一次删除几个？ Three+Two+One = TTO 为Bksp按钮的删除方式提供依据
* 返回3，表示str尾部为sin、cos、tan、log中的一个，应当一次删除3个 返回2，表示str尾部为ln、n!中的一个，应当一次删除2个
* 返回1，表示为除返回3、2外的所有情况，只需删除一个（包含非法字符时要另外考虑：应清屏）
*/
private int TTO(String str) {
if ((str.charAt(str.length() - 1) == 'n'
&& str.charAt(str.length() - 2) == 'i' && str.charAt(str
.length() - 3) == 's')
|| (str.charAt(str.length() - 1) == 's'
&& str.charAt(str.length() - 2) == 'o' && str
.charAt(str.length() - 3) == 'c')
|| (str.charAt(str.length() - 1) == 'n'
&& str.charAt(str.length() - 2) == 'a' && str
.charAt(str.length() - 3) == 't')
|| (str.charAt(str.length() - 1) == 'g'
&& str.charAt(str.length() - 2) == 'o' && str
.charAt(str.length() - 3) == 'l')) {
return 3;
} else if ((str.charAt(str.length() - 1) == 'n' && str.charAt(str
.length() - 2) == 'l')
|| (str.charAt(str.length() - 1) == '!' && str.charAt(str
.length() - 2) == 'n')) {
return 2;
} else {
return 1;
}
}
/*
* 判断一个str是否是合法的，返回值为true、false
* 只包含0123456789.()sincostanlnlogn!+-×÷√^的是合法的str，返回true
* 包含了除0123456789.()sincostanlnlogn!+-×÷√^以外的字符的str为非法的，返回false
*/
private boolean right(String str) {
int i = 0;
for (i = 0; i < str.length(); i++) {
if (str.charAt(i) != '0' && str.charAt(i) != '1'
&& str.charAt(i) != '2' && str.charAt(i) != '3'
&& str.charAt(i) != '4' && str.charAt(i) != '5'
&& str.charAt(i) != '6' && str.charAt(i) != '7'
&& str.charAt(i) != '8' && str.charAt(i) != '9'
&& str.charAt(i) != '.' && str.charAt(i) != '-'
&& str.charAt(i) != '+' && str.charAt(i) != '×'
&& str.charAt(i) != '÷' && str.charAt(i) != '√'
&& str.charAt(i) != '^' && str.charAt(i) != 's'
&& str.charAt(i) != 'i' && str.charAt(i) != 'n'
&& str.charAt(i) != 'c' && str.charAt(i) != 'o'
&& str.charAt(i) != 't' && str.charAt(i) != 'a'
&& str.charAt(i) != 'l' && str.charAt(i) != 'g'
&& str.charAt(i) != '(' && str.charAt(i) != ')'
&& str.charAt(i) != '!')
break;
}
if (i == str.length()) {
return true;
} else {
return false;
}
}
/*
* 整个计算核心，
* 只要将表达式的整个字符串传入calc().process()就可以实行计算了 算法包括以下几部分：
* 1、计算部分
* process(String str) 当然，这是建立在查错无错误的情况下
* 2、数据格式化 FP(double n) 使数据有相当的精确度
* 3、阶乘算法 N(double n) 计算n!，将结果返回
* 4、错误提示 showError(int code ,String str)
* 将错误返回
*/
public class calc {
public calc() {
}
final int MAXLEN = 500;
/*
* 计算表达式 从左向右扫描，数字入number栈，运算符入operator栈
* +-基本优先级为1，
* ×÷基本优先级为2，
* log ln sin cos tan n!基本优先级为3，
* √^基本优先级为4
* 括号内层运算符比外层同级运算符优先级高4
* 当前运算符优先级高于栈顶压栈，
* 低于栈顶弹出一个运算符与两个数进行运算
* 重复直到当前运算符大于栈顶
* 扫描完后对剩下的运算符与数字依次计算
*/
public void process(String str) {
int weightPlus = 0, topOp = 0, topNum = 0, flag = 1, weightTemp = 0;
// weightPlus为同一（）下的基本优先级，weightTemp临时记录优先级的变化
// topOp为weight[]，operator[]的计数器；topNum为number[]的计数器
// flag为正负数的计数器，1为正数，-1为负数
int weight[]; // 保存operator栈中运算符的优先级，以topOp计数
double number[]; // 保存数字，以topNum计数
char ch, ch_gai, operator[];// operator[]保存运算符，以topOp计数
String num;// 记录数字，str以+-×÷()sctgl!√^分段，+-×÷()sctgl!√^字符之间的字符串即为数字
weight = new int[MAXLEN];
number = new double[MAXLEN];
operator = new char[MAXLEN];
String expression = str;
StringTokenizer expToken = new StringTokenizer(expression,
"+-×÷()sctgl!√^");
int i = 0;
while (i < expression.length()) {
ch = expression.charAt(i);
// 判断正负数
if (i == 0) {
if (ch == '-')
flag = -1;
} else if (expression.charAt(i - 1) == '(' && ch == '-')
flag = -1;
// 取得数字，并将正负符号转移给数字
if (ch <= '9' && ch >= '0' || ch == '.' || ch == 'E') {
num = expToken.nextToken();
ch_gai = ch;
Log.e("guojs", ch + "--->" + i);
// 取得整个数字
while (i < expression.length()
&& (ch_gai <= '9' && ch_gai >= '0' || ch_gai == '.' || ch_gai == 'E')) {
ch_gai = expression.charAt(i++);
Log.e("guojs", "i的值为：" + i);
}
// 将指针退回之前的位置
if (i >= expression.length())
i -= 1;
else {
i -= 2;
}
if (num.compareTo(".") == 0)
number[topNum++] = 0;
// 将正负符号转移给数字
else {
number[topNum++] = Double.parseDouble(num) * flag;
flag = 1;
}
}
// 计算运算符的优先级
if (ch == '(')
weightPlus += 4;
if (ch == ')')
weightPlus -= 4;
if (ch == '-' && flag == 1 || ch == '+' || ch == '×'
|| ch == '÷' || ch == 's' || ch == 'c' || ch == 't'
|| ch == 'g' || ch == 'l' || ch == '!' || ch == '√'
|| ch == '^') {
switch (ch) {
// +-的优先级最低，为1
case '+':
case '-':
weightTemp = 1 + weightPlus;
break;
// x÷的优先级稍高，为2
case '×':
case '÷':
weightTemp = 2 + weightPlus;
break;
// sincos之类优先级为3
case 's':
case 'c':
case 't':
case 'g':
case 'l':
case '!':
weightTemp = 3 + weightPlus;
break;
// 其余优先级为4
// case '^':
// case '√':
default:
weightTemp = 4 + weightPlus;
break;
}
// 如果当前优先级大于堆栈顶部元素，则直接入栈
if (topOp == 0 || weight[topOp - 1] < weightTemp) {
weight[topOp] = weightTemp;
operator[topOp] = ch;
topOp++;
// 否则将堆栈中运算符逐个取出，直到当前堆栈顶部运算符的优先级小于当前运算符
} else {
while (topOp > 0 && weight[topOp - 1] >= weightTemp) {
switch (operator[topOp - 1]) {
// 取出数字数组的相应元素进行运算
case '+':
number[topNum - 2] += number[topNum - 1];
break;
case '-':
number[topNum - 2] -= number[topNum - 1];
break;
case '×':
number[topNum - 2] *= number[topNum - 1];
break;
// 判断除数为0的情况
case '÷':
if (number[topNum - 1] == 0) {
showError(1, str_old);
return;
}
number[topNum - 2] /= number[topNum - 1];
break;
case '√':
if (number[topNum - 1] == 0
|| (number[topNum - 2] < 0 && number[topNum - 1] % 2 == 0)) {
showError(2, str_old);
return;
}
number[topNum - 2] = Math.pow(
number[topNum - 2],
1 / number[topNum - 1]);
break;
case '^':
number[topNum - 2] = Math.pow(
number[topNum - 2], number[topNum - 1]);
break;
// 计算时进行角度弧度的判断及转换
// sin
case 's':
if (drg_flag == true) {
number[topNum - 1] = Math
.sin((number[topNum - 1] / 180)
* pi);
} else {
number[topNum - 1] = Math
.sin(number[topNum - 1]);
}
topNum++;
break;
// cos
case 'c':
if (drg_flag == true) {
number[topNum - 1] = Math
.cos((number[topNum - 1] / 180)
* pi);
} else {
number[topNum - 1] = Math
.cos(number[topNum - 1]);
}
topNum++;
break;
// tan
case 't':
if (drg_flag == true) {
if ((Math.abs(number[topNum - 1]) / 90) % 2 == 1) {
showError(2, str_old);
return;
}
number[topNum - 1] = Math
.tan((number[topNum - 1] / 180)
* pi);
} else {
if ((Math.abs(number[topNum - 1]) / (pi / 2)) % 2 == 1) {
showError(2, str_old);
return;
}
number[topNum - 1] = Math
.tan(number[topNum - 1]);
}
topNum++;
break;
// log
case 'g':
if (number[topNum - 1] <= 0) {
showError(2, str_old);
return;
}
number[topNum - 1] = Math
.log10(number[topNum - 1]);
topNum++;
break;
// ln
case 'l':
if (number[topNum - 1] <= 0) {
showError(2, str_old);
return;
}
number[topNum - 1] = Math
.log(number[topNum - 1]);
topNum++;
break;
// 阶乘
case '!':
if (number[topNum - 1] > 170) {
showError(3, str_old);
return;
} else if (number[topNum - 1] < 0) {
showError(2, str_old);
return;
}
number[topNum - 1] = N(number[topNum - 1]);
topNum++;
break;
}
// 继续取堆栈的下一个元素进行判断
topNum--;
topOp--;
}
// 将运算符如堆栈
weight[topOp] = weightTemp;
operator[topOp] = ch;
topOp++;
}
}
i++;
}
// 依次取出堆栈的运算符进行运算
while (topOp > 0) {
// +-x直接将数组的后两位数取出运算
switch (operator[topOp - 1]) {
case '+':
number[topNum - 2] += number[topNum - 1];
break;
case '-':
number[topNum - 2] -= number[topNum - 1];
break;
case '×':
number[topNum - 2] *= number[topNum - 1];
break;
// 涉及到除法时要考虑除数不能为零的情况
case '÷':
if (number[topNum - 1] == 0) {
showError(1, str_old);
return;
}
number[topNum - 2] /= number[topNum - 1];
break;
case '√':
if (number[topNum - 1] == 0
|| (number[topNum - 2] < 0 && number[topNum - 1] % 2 == 0)) {
showError(2, str_old);
return;
}
number[topNum - 2] = Math.pow(number[topNum - 2],
1 / number[topNum - 1]);
break;
case '^':
number[topNum - 2] = Math.pow(number[topNum - 2],
number[topNum - 1]);
break;
// sin
case 's':
if (drg_flag == true) {
number[topNum - 1] = Math
.sin((number[topNum - 1] / 180) * pi);
} else {
number[topNum - 1] = Math.sin(number[topNum - 1]);
}
topNum++;
break;
// cos
case 'c':
if (drg_flag == true) {
number[topNum - 1] = Math
.cos((number[topNum - 1] / 180) * pi);
} else {
number[topNum - 1] = Math.cos(number[topNum - 1]);
}
topNum++;
break;
// tan
case 't':
if (drg_flag == true) {
if ((Math.abs(number[topNum - 1]) / 90) % 2 == 1) {
showError(2, str_old);
return;
}
number[topNum - 1] = Math
.tan((number[topNum - 1] / 180) * pi);
} else {
if ((Math.abs(number[topNum - 1]) / (pi / 2)) % 2 == 1) {
showError(2, str_old);
return;
}
number[topNum - 1] = Math.tan(number[topNum - 1]);
}
topNum++;
break;
// 对数log
case 'g':
if (number[topNum - 1] <= 0) {
showError(2, str_old);
return;
}
number[topNum - 1] = Math.log10(number[topNum - 1]);
topNum++;
break;
// 自然对数ln
case 'l':
if (number[topNum - 1] <= 0) {
showError(2, str_old);
return;
}
number[topNum - 1] = Math.log(number[topNum - 1]);
topNum++;
break;
// 阶乘
case '!':
if (number[topNum - 1] > 170) {
showError(3, str_old);
return;
} else if (number[topNum - 1] < 0) {
showError(2, str_old);
return;
}
number[topNum - 1] = N(number[topNum - 1]);
topNum++;
break;
}
// 取堆栈下一个元素计算
topNum--;
topOp--;
}
// 如果是数字太大，提示错误信息
if (number[0] > 7.3E306) {
showError(3, str_old);
return;
}
// 输出最终结果
input.setText(String.valueOf(FP(number[0])));
tip.setText("计算完毕，要继续请按归零键 C");
mem.setText(str_old + "=" + String.valueOf(FP(number[0])));
}
/*
* FP = floating point 控制小数位数，达到精度 否则会出现
* 0.6-0.2=0.39999999999999997的情况，用FP即可解决，使得数为0.4 本格式精度为15位
*/
public double FP(double n) {
// NumberFormat format=NumberFormat.getInstance(); //创建一个格式化类f
// format.setMaximumFractionDigits(18); //设置小数位的格式
// DecimalFormat format = new DecimalFormat("0.#############");
Double re = n;
String s = round(re.toString(),DEF_DIV_SCALE[0]);
return Double.parseDouble(s);
}
/*
* 阶乘算法
*/
public double N(double n) {
int i = 0;
double sum = 1;
// 依次将小于等于n的值相乘
for (i = 1; i <= n; i++) {
sum = sum * i;
}
return sum;
}
/*
* 错误提示，按了"="之后，若计算式在process()过程中，出现错误，则进行提示
*/
public void showError(int code, String str) {
String message = "";
switch (code) {
case 1:
message = "零不能作除数";
break;
case 2:
message = "函数格式错误";
break;
case 3:
message = "值太大了，超出范围";
}
input.setText("\"" + str + "\"" + ": " + message);
tip.setText(message + "\n" + "计算完毕，要继续请按归零键 C");
}
}
/**
*保存切换页面时EditEext中的值
*/
@Override //这种方式保存数据只是临时保存，无法永久保存
protected void onSaveInstanceState(@NonNull Bundle outState) { //该函数用于提取出历史数据，保存到outState中
super.onSaveInstanceState(outState);
init[0] = input.getText().toString();
outState.putString("exp",init[0]);
}
/**
*舍入精度
*/
public static String round(String v, int scale) {
if (scale < 0) {
throw new IllegalArgumentException(
"The scale must be a positive integer or zero");
}
BigDecimal b = new BigDecimal(v);
BigDecimal one = new BigDecimal("1");
BigDecimal re = b.divide(one, scale, BigDecimal.ROUND_HALF_UP);
return re.toString();
}
// @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;
// }
/**
*音量键事件
*/
@Override
public boolean onKeyDown (int keyCode, KeyEvent event) {
String s = input.getText().toString();
if(s.length()<1){
}else {
switch (keyCode) {
// 音量减小
case KeyEvent.KEYCODE_VOLUME_DOWN:
if(DEF_DIV_SCALE[0]>1)
DEF_DIV_SCALE[0]--;
seekBar.setProgress(DEF_DIV_SCALE[0]);
Toast.makeText(this.getApplicationContext(), "DOWN " + DEF_DIV_SCALE[0], Toast.LENGTH_SHORT).show();
if(s.contains(".")) input.setText(round(s,DEF_DIV_SCALE[0]));
// 音量减小时应该执行的功能代码
return true;
// 音量增大
case KeyEvent.KEYCODE_VOLUME_UP:
if(DEF_DIV_SCALE[0]<40)
DEF_DIV_SCALE[0]++;
seekBar.setProgress(DEF_DIV_SCALE[0]);
Toast.makeText(this.getApplicationContext(), "UP " + DEF_DIV_SCALE[0], Toast.LENGTH_SHORT).show();
if(s.contains(".")) input.setText(round(s,DEF_DIV_SCALE[0]));
// 音量增大时应该执行的功能代码
return true;
}
}
return super.onKeyDown (keyCode, event);
}
/**
* 滑动条事件
*/
public SeekBar.OnSeekBarChangeListener onSeekBarChangeListener = new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
//txt_cur.setText("当前进度值:" + progress + " / 100 ");
String s = input.getText().toString();
if(s.length()<1){
return;
}else{
if(progress>DEF_DIV_SCALE[0]){
DEF_DIV_SCALE[0] = progress;
Toast.makeText(getApplicationContext(), "UP " + DEF_DIV_SCALE[0], Toast.LENGTH_SHORT).show();
if(s.contains(".")) input.setText(round(s,DEF_DIV_SCALE[0]));
}else if(progress
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脚本之家。