import android.os.Bundle;

 import android.view.View;

 import android.view.View.OnClickListener;

 import android.widget.Button;

 import android.app.Activity;

 import android.content.Intent;

 public class FirstActivity extends Activity {

     private Button myButton;

     @Override

     protected void onCreate(Bundle savedInstanceState) {

         System.out.println("FirstActivity ---> onCreate     ");

         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_first);

         myButton = (Button) findViewById(R.id.myButton);

         myButton.setOnClickListener(new ButtonListener());

     }

     @Override

     protected void onDestroy() {

         System.out.println("FirstAcvity --->onDestory");

         super.onDestroy();

     }

     @Override

     protected void onPause() {

         System.out.println("FirstAcvity --->onPause");

         super.onPause();

     }

     @Override

     protected void onRestart() {

         System.out.println("FirstAcvity --->onRestart");

         super.onRestart();

     }

     @Override

     protected void onResume() {

         System.out.println("FirstAcvity --->onResume");

         super.onResume();

     }

     @Override

     protected void onStart() {

         System.out.println("FirstAcvity --->onStart");

         super.onStart();

     }

     @Override

     protected void onStop() {

         System.out.println("FirstAcvity --->onStop");

         super.onStop();

     }

     class ButtonListener implements OnClickListener{

         @Override

         public void onClick(View v) {

             Intent intent = new Intent();

             intent.setClass(FirstActivity.this, SecondActivity.class);

             FirstActivity.this.startActivity(intent);

         }

     }

 }

 <?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"

     >

 <TextView

     android:layout_width="fill_parent"

     android:layout_height="wrap_content"

     android:text="@string/hello_world"

     />

 <Button

     android:id="@+id/myButton"

     android:layout_width="fill_parent"

     android:layout_height="wrap_content"

     android:text="@string/first_button"

     />

 </LinearLayout>

 import android.app.Activity;

 import android.content.Intent;

 import android.os.Bundle;

 import android.view.View;

 import android.view.View.OnClickListener;

 import android.widget.Button;

 public class SecondActivity extends Activity{

     private Button secondButton;

     @Override

     protected void onCreate(Bundle savedInstanceState) {

         System.out.println("SecondActivity--->onCreate");

         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_second);

         secondButton = (Button)findViewById(R.id.secondButton);

         secondButton.setOnClickListener(new ButtonListener());

     }

     @Override

     protected void onDestroy() {

         System.out.println("SecondActivity--->onDestory");

         super.onDestroy();

     }

     @Override

     protected void onPause() {

         System.out.println("SecondActivity--->onPause");

         super.onPause();

     }

     @Override

     protected void onRestart() {

         System.out.println("SecondActivity--->onRestart");

         super.onRestart();

     }

     @Override

     protected void onResume() {

         System.out.println("SecondActivity--->onResume");

         super.onResume();

     }

     @Override

     protected void onStart() {

         System.out.println("SecondActivity--->onStart");

         super.onStart();

     }

     @Override

     protected void onStop() {

         System.out.println("SecondActivity--->onStop");

         super.onStop();

     }

     class ButtonListener implements OnClickListener{

         @Override

         public void onClick(View v) {

             Intent intent = new Intent();

             intent.setClass(SecondActivity.this, FirstActivity.class);

             SecondActivity.this.startActivity(intent);

         }

     }

 }

 <?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="wrap_content"

     >

     <TextView

         android:layout_width="fill_parent"

         android:layout_height="wrap_content"

         />

        <Button

            android:id="@+id/secondButton"

            android:layout_width="fill_parent"

            android:layout_height="wrap_content"

            android:text="@string/second_button"

            />

 </LinearLayout>

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.mars.activity05"

    android:versionCode="1"

    android:versionName="1.0" >

    <uses-sdk

        android:minSdkVersion="4"

        android:targetSdkVersion="18" />

    <application

        android:allowBackup="true"

        android:icon="@drawable/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name="com.mars.activity05.FirstActivity"

            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=".SecondActivity"

                  android:label="SecondActivity"

                  android:theme="@android:style/Theme.Dialog"/>

        <!--android:theme="@android:style/Theme.Dialog"/>,表示将这个Activity的格式设置为，对话框的形式-->

    </application>

</manifest>

<?xml version="1.0" encoding="utf-8"?>

<resources>

    <string name="app_name">Activity05</string>

    <string name="action_settings">Settings</string>

    <string name="hello_world">Hello world!</string>

    <string name="first_button">FirstButton</string>

    <string name="second_button">SecondButton</string>

</resources>