package com.example.sjq;
import java.util.Iterator;
import java.util.LinkedList;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends Activity implements OnClickListener {
private Button btn_zero;
private Button btn_one;
private Button btn_two;
private Button btn_three;
private Button btn_four;
private Button btn_five;
private Button btn_six;
private Button btn_seven;
private Button btn_eight;
private Button btn_nine;
private Button btn_plus;
private Button btn_sub;
private Button btn_mul;
private Button btn_div;
private Button btn_point;
private Button btn_equal;
private Button btn_del;
private Button btn_c;
private EditText et;
LinkedList<String> center = new LinkedList<String>();// 对et进行解析，即存放中缀表达式的链表
LinkedList<String> postfix = new LinkedList<String>();// 存放后缀表达式的链表
LinkedList<Double> data = new LinkedList<Double>();// 存放后缀表达式的数字链表
LinkedList<String> op = new LinkedList<String>();// 1：作为临时存放运算符的链表；2：存放后缀表达式的运算符
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initview();
}
private void initview() {
btn_one = (Button) findViewById(R.id.btn_one);
btn_two = (Button) findViewById(R.id.btn_two);
btn_three = (Button) findViewById(R.id.btn_three);
btn_four = (Button) findViewById(R.id.btn_four);
btn_five = (Button) findViewById(R.id.btn_five);
btn_six = (Button) findViewById(R.id.btn_six);
btn_seven = (Button) findViewById(R.id.btn_seven);
btn_eight = (Button) findViewById(R.id.btn_eight);
btn_nine = (Button) findViewById(R.id.btn_nine);
btn_plus = (Button) findViewById(R.id.btn_plus);
btn_sub = (Button) findViewById(R.id.btn_sub);
btn_mul = (Button) findViewById(R.id.btn_mul);
btn_div = (Button) findViewById(R.id.btn_div);
btn_point = (Button) findViewById(R.id.btn_point);
btn_equal = (Button) findViewById(R.id.btn_equal);
btn_one = (Button) findViewById(R.id.btn_one);
btn_del = (Button) findViewById(R.id.btn_del);
btn_c = (Button) findViewById(R.id.btn_c);
btn_zero = (Button) findViewById(R.id.btn_zero);
btn_one.setOnClickListener(this);
btn_two.setOnClickListener(this);
btn_three.setOnClickListener(this);
btn_four.setOnClickListener(this);
btn_five.setOnClickListener(this);
btn_six.setOnClickListener(this);
btn_seven.setOnClickListener(this);
btn_eight.setOnClickListener(this);
btn_nine.setOnClickListener(this);
btn_plus.setOnClickListener(this);
btn_sub.setOnClickListener(this);
btn_mul.setOnClickListener(this);
btn_div.setOnClickListener(this);
btn_equal.setOnClickListener(this);
btn_point.setOnClickListener(this);
btn_del.setOnClickListener(this);
btn_c.setOnClickListener(this);
btn_zero.setOnClickListener(this);
et = (EditText) findViewById(R.id.edit);
}
@Override
public void onClick(View v) {
String str = et.getText().toString();
switch (v.getId()) {
case R.id.btn_c:
et.setText("");
break;
case R.id.btn_one:
case R.id.btn_two:
case R.id.btn_three:
case R.id.btn_four:
case R.id.btn_five:
case R.id.btn_six:
case R.id.btn_seven:
case R.id.btn_eight:
case R.id.btn_nine:
case R.id.btn_zero:
case R.id.btn_point:
case R.id.btn_div:
case R.id.btn_mul:
case R.id.btn_plus:
case R.id.btn_sub:
str = ((TextView) v).getText();
et.setText(str);
et.setSelection(et.getText().length());
break;
case R.id.btn_equal:
getresult(str);
break;
case R.id.btn_del:
if (str.length() >= 1)
et.setText(str.substring(0, str.length() - 1));
break;
default:
break;
}
}
private void getresult(String str) {
MainActivity.this.Analysis(str);// 调用Analysis函数对et进行解析
Iterator<String> it = center.iterator();
while (it.hasNext()) {
String tmpstr = it.next();
if (isNum(tmpstr)) {
postfix.addLast(tmpstr);
} else {
int peeklevel = op.isEmpty() ? 0 : getLevel(op.getLast());
if (getLevel(tmpstr) > peeklevel) {
op.addLast(tmpstr);
} else {
String str2 = op.removeLast();
while (getLevel(str2) >= peeklevel) {
postfix.addLast(str2);
if (op.isEmpty()) {
break;
}
str2 = op.removeLast();
}
op.addLast(tmpstr);
}
}
}
center.clear();
if (postfix.size() <= op.size()) {
et.setText("");
postfix.clear();
op.clear();
} else {
while (!op.isEmpty()) {
postfix.addLast(op.removeLast());
}
System.out.println(postfix);
while (!(postfix.isEmpty())) {
String tmpstr = postfix.removeFirst();
if (isOp(tmpstr)) {
char ch = tmpstr.charAt(0);
Double first = data.removeLast();
Double last = data.removeLast();
switch (ch) {
case '*':
data.addLast(last * first);
break;
case '/':
data.addLast(last / first);
break;
case ' ':
data.addLast(last first);
break;
case '-':
data.addLast(last - first);
break;
}
} else {
data.addLast(Double.parseDouble(tmpstr));
}
}
Double result = data.removeFirst();
et.setText(Double.toString(result));
et.setSelection(et.getText().length());
}
}
public boolean isNum(String str) {
int num = 0;
for (int i = 0; i < str.length(); i ) {
String strr = str.substring(i, i 1);
if (strr.equals("0") || strr.equals("1") || strr.equals("2")
|| strr.equals("3") || strr.equals("4") || strr.equals("5")
|| strr.equals("6") || strr.equals("7") || strr.equals("8")
|| strr.equals("9") || strr.equals("."))
num = num 1;
}
if (num == str.length())
return true;
else
return false;
}
public boolean isOp(String strr) {
if (strr.equals(" ") || strr.equals("-") || strr.equals("*")
|| strr.equals("/"))
return true;
else
return false;
}
public int getLevel(String str) {
if (str.equals("*") || str.equals("/")) {
return 2;
} else if (str.equals(" ") || str.equals("-")) {
return 1;
} else {
return 0;
}
}
public void Analysis(String str) {
String sub = "";
for (int i = 0; i < str.length(); i ) {
String strr = str.substring(i, i 1);
if (isNum(strr)) {
sub = strr;
} else {
if (sub != "") {
center.addLast(sub);// 首先sub进center
sub = "";// 将sub清空
}
center.addLast(strr);// " -*/" "(" ")" 则直接进center表
}
}
if (isNum(str.substring(str.length() - 1))) {
center.addLast(sub);// 首先sub进center
sub = "";// 将sub清空
}
}
}
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