这里主要是讲activity之间的跳转，媒介就是intent，当然一种是直接跳转没有数据传输的，一种是有数据传输的，这里讲有数据传输的
MainActivity.java[java]
package com.example.anpro03;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;

import android.location.GpsStatus.Listener;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.Intent;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends Activity {
EditText e1;
Button bt1;
String result;
// MyHandler myHandler;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
e1 = (EditText) findViewById(R.id.editText1);
bt1 = (Button) findViewById(R.id.button1);

bt1.setOnClickListener(listener);
}

@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;
}

private Handler handler = new Handler(){
public void handleMessage(android.os.Message msg){

}
};

private OnClickListener listener = new OnClickListener(){

@Override
public void onClick(View v) {
Intent distIntent = new Intent(MainActivity.this,MyActivity01.class);
EditText e1 = (EditText) findViewById(R.id.editText1);
distIntent.putExtra("key", e1.getText().toString());
startActivity(distIntent);
}

};

}
[/java]
MyActivity01.java[java]
package com.example.anpro03;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.TextView;

public class MyActivity01 extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my_activity01);

Bundle extras = getIntent().getExtras();
String mText = extras.getString("key");
TextView tShow = (TextView) findViewById(R.id.txtshow);
tShow.setText(mText);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.my_activity01, menu);
return true;
}

}
[/java]
activity_main.xml[xml]
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >

<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world" />

<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView1"
android:layout_marginTop="77dp"
android:text="Button" />

<EditText
android:id="@+id/editText1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/button1"
android:layout_below="@+id/textView1"
android:layout_marginTop="26dp"
android:ems="10" >

<requestFocus />
</EditText>

</RelativeLayout>[/xml]
activity_my_activity01.xml[xml]
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MyActivity01" >

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world" />
<TextView
android:id="@+id/txtshow"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:text="@string/hello_world" />

</RelativeLayout>[/xml]