首先设置两个布局文件，一个布局文件进行输入数据，获取加法运算；另一个布局文件进行显示最终结果。Activity1启动Activity2，并传递计算结果值给Activity2.

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="fill_parent"android:layout_height="fill_parent">
<EditText android:id="@+id/factorOne"android:layout_width="fill_parent" android:layout_height="wrap_content" />
<TextView  android:id="@+id/symbol"android:layout_width="fill_parent" android:layout_height="wrap_content" />
<EditText android:id="@+id/factorTwo"android:layout_width="fill_parent" android:layout_height="wrap_content" />
<Buttonandroid:id="@+id/calculate"android:layout_width="fill_parent" android:layout_height="wrap_content" />
</LinearLayout>

页面展示：

result.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="vertical"android:layout_width="fill_parent"android:layout_height="fill_parent"><TextViewandroid:id="@+id/result"android:layout_width="fill_parent"android:layout_height="wrap_content"/>
</LinearLayout>

界面展示：

activity03活动：

package mars.activity03;import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
//1.在Activity03当中，要声明四个控件
//2.要为其中的两个控件设置显示的值
//3.创建一个监听器类，监听按钮按下的动作
//4.将监听器类的对象，绑定在按钮对象上
public class Activity03 extends Activity {/** Called when the activity is first created. */private EditText factorOne ;private EditText factorTwo;private TextView symbol;private Button calculate;@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);//根据控件的ID来取得代表控件的对象factorOne = (EditText)findViewById(R.id.factorOne);factorTwo = (EditText)findViewById(R.id.factorTwo);symbol = (TextView)findViewById(R.id.symbol);calculate = (Button)findViewById(R.id.calculate);//为symbol和calculate设置显示的值
//        symbol.setText("乘以");
//        calculate.setText("计算");symbol.setText(R.string.symbol);//这里通过引用的方式，去String文件中引用。保证了业务逻辑、视图、引用资源分开calculate.setText(R.string.calculate);//将监听器的对象绑定到按钮对象上面calculate.setOnClickListener(new CalculateListener());}//当客户点击MENU按钮的时候，调用该方法@Overridepublic boolean onCreateOptionsMenu(Menu menu) {menu.add(0, 1, 1, R.string.exit);menu.add(0,2,2,R.string.about);return super.onCreateOptionsMenu(menu);}//当客户点击菜单当中的某一个选项时，会调用该方法@Overridepublic boolean onOptionsItemSelected(MenuItem item) {if(item.getItemId() == 1){finish();}return super.onOptionsItemSelected(item);}class CalculateListener implements OnClickListener{@Overridepublic void onClick(View v) {//取得两个EditText控件的值String factorOneStr = factorOne.getText().toString();String factorTwoStr = factorTwo.getText().toString();//将这两个值存放到Intent对象当中Intent intent = new Intent();intent.putExtra("one",factorOneStr);intent.putExtra("two",factorTwoStr);intent.setClass(Activity03.this, ResultActivity.class);//使用这个Intent对象来启动ResultActivityActivity03.this.startActivity(intent);}}
}

resultActivity:

package mars.activity03;import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
//1.接受从Activity03当中所传递的值
//2.计算两个值的积
//3.将计算的结果显示在Activity上
public class ResultActivity extends Activity{private TextView resultView;@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.result);resultView = (TextView)findViewById(R.id.result);//得到Intent对象当中的值 Intent intent = getIntent();String factorOneStr = intent.getStringExtra("one");String factorTwoStr = intent.getStringExtra("two");int factorOneInt = Integer.parseInt(factorOneStr);int factorTwoInt = Integer.parseInt(factorTwoStr);//计算两个值的积int result = factorOneInt * factorTwoInt;resultView.setText(result + "");}}

String.xml:

<?xml version="1.0" encoding="utf-8"?>
<resources><string name="hello">Hello World, Activity03!</string><string name="app_name">activity03</string><string name="resultLabel">result</string><string name="symbol">乘以</string><string name="calculate">计算</string><string name="exit">退出</string><string name="about">关于</string>
</resources>

最后再看一下配置文件：活动都要进行注册，并且设置Activity03为主活动

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"package="mars.activity03"android:versionCode="1"android:versionName="1.0"><application android:icon="@drawable/icon" android:label="@string/app_name"><activity android:name=".Activity03"android:label="@string/app_name"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity><activity android:name=".ResultActivity" android:label="@string/resultLabel"/><!--这里使ResultActivity标题栏显示result--></application><uses-sdk android:minSdkVersion="4" /></manifest> 

运行结果：