Android计算器编程实现
成都创新互联公司主要从事网站制作、成都网站制作、网页设计、企业做网站、公司建网站等业务。立足成都服务新民,十年网站建设经验,价格优惠、服务专业,欢迎来电咨询建站服务:13518219792
第一步：定义所需的字符 string.xml
第二步：编辑界面 activity.main.xml
android:layout_width="match_parent" android:layout_height="match_parent" > android:id="@+id/text1" android:layout_width="320dp" android:layout_height="60dp" android:textSize="40sp" />
android:id="@+id/text2" android:layout_width="320dp" android:layout_height="60dp" android:textSize="40sp"/> android:id="@+id/button_clear" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/clear" android:textSize="20sp" /> android:id="@+id/button_chu" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/chu" android:textSize="20sp" /> android:id="@+id/button_cheng" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/cheng" android:textSize="20sp" /> android:id="@+id/button_tui" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/tui" android:textSize="20sp" /> android:id="@+id/button_qi" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/qi" android:textSize="30sp" /> android:id="@+id/button_ba" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/ba" android:textSize="30sp" /> android:id="@+id/button_jiu" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/jiu" android:textSize="30sp" /> android:id="@+id/button_jian" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/jian" android:textSize="30sp" /> android:id="@+id/button_si" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/si" android:textSize="30sp" /> android:id="@+id/button_wu" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/wu" android:textSize="30sp" /> android:id="@+id/button_liu" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/liu" android:textSize="30sp" /> android:id="@+id/button_jia" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/jia" android:textSize="30sp" /> android:id="@+id/button_yi" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/yi" android:textSize="30sp" /> android:id="@+id/button_er" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/er" android:textSize="30sp" /> android:id="@+id/button_san" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/san" android:textSize="30sp" /> android:id="@+id/button_dian" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/dian" android:textSize="30sp" /> android:id="@+id/button_ling" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/ling" android:textSize="30sp" /> android:id="@+id/button_kuohao_r" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/kuohao_r" android:textSize="30sp" /> android:id="@+id/button_kuohao_l" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/kuohao_l" android:textSize="30sp" /> android:id="@+id/button_deng" android:layout_width="80dp" android:layout_height="70dp" android:text="@string/deng" android:textSize="30sp" /> 第三步：编写处理四则运算（包含括号）的类 Yuansuan.class package com.malakana.cal; import android.annotation.SuppressLint; import java.util.*; public class Yunsuan { Yunsuan(String str1) { EvaluateExpression(str1); } @SuppressLint("UseValueOf") public static String EvaluateExpression(String str) { char[] a; int i = 0; a = str.toCharArray(); Stack Stack OPTR.push('='); float number = 0; int decimalnum = 1; boolean integer = false; boolean decimal = false; while (true) { if (i == str.length()) break; if (In(a[i]) == -1) { number = number * 10 + (a[i] - 48); integer = true; if (decimal) decimalnum = decimalnum * 10; i++; } else if (a[i] == '.') { if (decimal) return "ERROR"; decimal = integer = true; i++; } else if (In(a[i]) > -1 && In(a[i]) < 7) { if (In(a[i]) == 1 && (i == 0 || In(a[i - 1]) == 4)) OPND.push(new Float(0)); if (integer) { OPND.push(new Float(number / decimalnum)); number = 0; decimalnum = 1; integer = decimal = false; } switch (Precede(In(OPTR.peek()), In(a[i]))) { case 2: if (OPND.empty()) return "ERROR"; float x = OPND.pop(); if (OPND.empty()) return "ERROR"; float y = OPND.pop(); char theta = OPTR.pop(); if (In(theta) == 3 && x == 0) return "ERROR"; OPND.push(new Float(Operate(y, theta, x))); break; case 1: OPTR.pop(); i++; break; case 0: OPTR.push(new Character(a[i])); i++; break; case -1: return "ERROR"; } } } if (OPND.empty()) return "ERROR"; else return ("" + OPND.peek()); } public static int In(char t) { int i = 0; if (t > 47 && t < 58) return -1; switch (t) { case '+': i = 0; break; case '-': i = 1; break; case '*': i = 2; break; case '/': i = 3; break; case '(': i = 4; break; case ')': i = 5; break; case '=': i = 6; break; } return i; } public static int Precede(int t1, int t2) { int relationship[][] = { { 2, 2, 0, 0, 0, 2, 2 }, { 2, 2, 0, 0, 0, 2, 2 }, { 2, 2, 2, 2, 0, 2, 2 }, { 2, 2, 2, 2, 0, 2, 2 }, { 0, 0, 0, 0, 0, 1, -1 }, { 2, 2, 2, 2, -1, 2, 2 }, { 0, 0, 0, 0, 0, -1, 1 } }; return relationship[t1][t2]; } public static float Operate(float a, char theta, float b) { float i = 0; switch (theta) { case '+': i = a + b; break; case '-': i = a - b; break; case '*': i = a * b; break; case '/': i = a / b; break; } return i; } public static void main(String[] args) { new Yunsuan(null); } } 第四部： 编写主类 MianActivity.java package com.malakana.cal; import android.os.Bundle; import android.app.Activity; import android.view.Menu; import android.view.View; import android.view.View.OnClickListener; import android.widget.*; public class MainActivity extends Activity implements OnClickListener { String str = ""; String str1 = ""; String suanfa; TextView text1; TextView text2; Button button_jia; Button button_jian; Button button_cheng; Button button_chu; Button button_clear; Button button_tui; Button button_deng; Button button_kuohao_l; Button button_kuohao_r; Button button_dian; Button button_yi; Button button_er; Button button_san; Button button_si; Button button_wu; Button button_liu; Button button_qi; Button button_ba; Button button_jiu; Button button_ling; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); text1 = (TextView) findViewById(R.id.text1); text2 = (TextView) findViewById(R.id.text2); text1.setTextSize(20); text2.setTextSize(20); button_jia = (Button) findViewById(R.id.button_jia); button_jia.setTextSize(17); button_jian = (Button) findViewById(R.id.button_jian); button_jian.setTextSize(17); button_cheng = (Button) findViewById(R.id.button_cheng); button_cheng.setTextSize(17); button_chu = (Button) findViewById(R.id.button_chu); button_chu.setTextSize(17); button_dian = (Button) findViewById(R.id.button_dian); button_dian.setTextSize(17); button_deng = (Button) findViewById(R.id.button_deng); button_clear = (Button) findViewById(R.id.button_clear); button_tui = (Button) findViewById(R.id.button_tui); button_jian = (Button) findViewById(R.id.button_jian); button_kuohao_l = (Button) findViewById(R.id.button_kuohao_l); button_kuohao_r = (Button) findViewById(R.id.button_kuohao_r); button_yi = (Button) findViewById(R.id.button_yi); button_er = (Button) findViewById(R.id.button_er); button_san = (Button) findViewById(R.id.button_san); button_si = (Button) findViewById(R.id.button_si); button_wu = (Button) findViewById(R.id.button_wu); button_liu = (Button) findViewById(R.id.button_liu); button_qi = (Button) findViewById(R.id.button_qi); button_ba = (Button) findViewById(R.id.button_ba); button_jiu = (Button) findViewById(R.id.button_jiu); button_ling = (Button) findViewById(R.id.button_ling); button_jia.setOnClickListener(this); button_jian.setOnClickListener(this); button_cheng.setOnClickListener(this); button_chu.setOnClickListener(this); button_dian.setOnClickListener(this); button_clear.setOnClickListener(this); button_tui.setOnClickListener(this); button_deng.setOnClickListener(this); button_kuohao_l.setOnClickListener(this); button_kuohao_r.setOnClickListener(this); button_yi.setOnClickListener(this); button_er.setOnClickListener(this); button_san.setOnClickListener(this); button_si.setOnClickListener(this); button_wu.setOnClickListener(this); button_liu.setOnClickListener(this); button_qi.setOnClickListener(this); button_ba.setOnClickListener(this); button_jiu.setOnClickListener(this); button_ling.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 void onClick(View v) { // TODO Auto-generated method stub Button listener = (Button) v; if (listener.getText().equals("1") || listener.getText().equals("2") || listener.getText().equals("3") || listener.getText().equals("4") || listener.getText().equals("5") || listener.getText().equals("6") || listener.getText().equals("7") || listener.getText().equals("8") || listener.getText().equals("9") || listener.getText().equals("0") || listener.getText().equals(".")) { str = str + listener.getText(); } else if (listener.getText().equals("+") || listener.getText().equals("-") || listener.getText().equals("*") || listener.getText().equals("/") || listener.getText().equals("(") || listener.getText().equals(")")) { if (str1.endsWith("=")) { str1 = ""; } str = str + listener.getText(); str1 = str1 + str; str = ""; } else if (listener.getText().equals("=")) { if(str1.endsWith("=")){ str1=""; } str = str + listener.getText(); str1 = str1 + str; str=Yunsuan.EvaluateExpression(str1); //double m = 0; //m = CalcStr.calc(str1); //str1 = str1 + "="; //str = m + ""; } else if (listener.getText().equals("Back")) { if (str.length() >= 1) { str = str.substring(0, str.length() - 1); } else { str1 = ""; str = ""; } } else if (listener.getText().equals("Clear")) { str = ""; str1 = ""; } text2.setText(str); text1.setText(str1); text1.setTextSize(TRIM_MEMORY_BACKGROUND); text2.setTextSize(TRIM_MEMORY_BACKGROUND); } } 最后编译实现 run for Android Application
网站标题：Android计算器编程实现
文章出自：http://pwwzsj.com/article/pijghc.html
