a n d r o i d简单计算器欢迎大家补充package com.example.zzz;//此文使用了fragment的模块。

//此文使用了fragment的模块。

//此文使用了fragment的模块。

//此文使用了fragment的模块。

import android.support.v7.app.ActionBarActivity;import android.support.v7.app.ActionBar;import android.support.v4.app.Fragment;import android.os.Bundle;import youtInflater;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.ViewGroup;import android.widget.Button;import android.widget.EditText;import android.widget.TextView;import android.widget.Toast;import android.os.Build;public class MainActivity extends ActionBarActivity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(yout.activity_main);if (savedInstanceState == null) {getSupportFragmentManager().beginTransaction().add(R.id.container, new PlaceholderFragment()).commit();}}@Overridepublic 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;}@Overridepublic boolean onOptionsItemSelected(MenuItem item) {// Handle action bar item clicks here. The action bar will// automatically handle clicks on the Home/Up button, so long// as you specify a parent activity in AndroidManifest.xml.int id = item.getItemId();if (id == R.id.action_settings) {return true;}return super.onOptionsItemSelected(item);}/*** A placeholder fragment containing a simple view.*/public static class PlaceholderFragment extends Fragment { //此文使用了fragment的模块。

private double a,b;private int num=0;private Button button1;private Button button2;private Button button3;private Button button4;private Button button5;private Button button6;private Button button7;private Button button8;private Button button9;private Button button0;private Button buttonjia;private Button buttonjian;private Button buttoncheng;private Button buttonchu;private Button buttonxiaoshudian;private Button buttonqingchu;private Button buttondengyu;private TextView text;public PlaceholderFragment() {}@Overridepublic View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {View rootView =inflater.inflate(yout.fragment_main, container,false);findbutton(rootView);//定义一个函数用于找组件ViewEvent(rootView);//定义一个函数。

用于初始化监听器（将组件与监听器相连接）//注意，设置监听器的时候必须保证找到了组件。

否则程序用易出错。

特别提醒return rootView;//使用fragment，此处的返回值必须为rootView，上面有函数可以看一下、}private void findbutton(View rootView){button0=(Button)rootView.findViewById(R.id.button0);button1=(Button)rootView.findViewById(R.id.button1);button2=(Button)rootView.findViewById(R.id.button2);button3=(Button)rootView.findViewById(R.id.button3);button4=(Button)rootView.findViewById(R.id.button4);button5=(Button)rootView.findViewById(R.id.button5);button6=(Button)rootView.findViewById(R.id.button6);button7=(Button)rootView.findViewById(R.id.button7);button8=(Button)rootView.findViewById(R.id.button8);button9=(Button)rootView.findViewById(R.id.button9);button0=(Button)rootView.findViewById(R.id.button0);buttonjia=(Button)rootView.findViewById(R.id.buttonjia);buttonjian=(Button)rootView.findViewById(R.id.buttonjian);buttoncheng=(Button)rootView.findViewById(R.id.buttoncheng);buttonchu=(Button)rootView.findViewById(R.id.buttonchu);buttonqingchu=(Button)rootView.findViewById(R.id.qingchu);buttondengyu=(Button)rootView.findViewById(R.id.buttondengyu );//text，找到文本编辑框组件，在下面需要传输值。

text =(TextView)rootView.findViewById(R.id.editText1);}private void ViewEvent(View rootView){button0.setOnClickListener(l);button1.setOnClickListener(l);button2.setOnClickListener(l);button3.setOnClickListener(l);button4.setOnClickListener(l);button5.setOnClickListener(l);button6.setOnClickListener(l);button7.setOnClickListener(l);button8.setOnClickListener(l);button9.setOnClickListener(l);buttonjia.setOnClickListener(l);buttonjian.setOnClickListener(l);buttoncheng.setOnClickListener(l);buttonchu.setOnClickListener(l);buttondengyu.setOnClickListener(l);buttonqingchu.setOnClickListener(l);}//实例化监听器：这一步必须的，相当于把监听器给物理化了。

View.OnClickListener l=new View.OnClickListener() {@Override//监听器实例化后会自动生成此方法，onClick函数中编辑简单计算器的方法。

public void onClick(View v) {// TODO Auto-generated method stubString s = text.getText().toString();//上面找到了文本编辑框，//接上句。

此处为将text中的内容传给s变量Button btn =(Button)v;String g=(String) btn.getText();//获取按钮的值。

if(btn.getId()==R.id.button0||btn.getId()==R.id.button1||btn.getId()==R.id.button2|| btn.getId()==R.id.button3||btn.getId()==R.id.button4||btn.getId()==R.id.button5||btn.getId()==R.id.button6||btn.getId()==R.id.button7||btn.getId()==R.id.button8||btn.getId()==R.id.button9){//此处含义：若按钮的id等于layout中的id，则text的值等于g（按钮的值）；text.setText(g);return;}if(btn.getId()==R.id.buttonjia){a=Double.parseDouble(s);num=1;text.setText("");return;}if(btn.getId()==R.id.buttonjian){a=Double.parseDouble(s);num=2;text.setText("");return;}if(btn.getId()==R.id.buttoncheng){a=Double.parseDouble(s);num=3;text.setText("");return;}if(btn.getId()==R.id.buttonchu){a=Double.parseDouble(s);num=4;text.setText("");return;}if(btn.getId()==R.id.qingchu){a=0;b=0;num=0;text.setText("");return;}if(btn.getId()==R.id.buttondengyu){b=Double.parseDouble(s);switch(num)//此处的num纯粹是为了switch 存在。