使用support v4包里的LocalBroadcastManager类方便得进行Service和Activity的交互

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="uk.ac.essex.LocalServiceBroadcaster"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk android:minSdkVersion="7" />

    <application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name" >
        <activity
            android:name=".LocalServiceBroadcasterActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <service
            android:name="LocalServiceBroadcasterActivity$LocalService"
            android:stopWithTask="true" >
        </service>
    </application>

</manifest>

LocalBroadcastManagerActivity类:

package uk.ac.essex.LocalServiceBroadcaster;

import android.app.Activity;
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.support.v4.app.ServiceCompat;
import android.support.v4.content.LocalBroadcastManager;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class LocalServiceBroadcasterActivity extends Activity {
	static final String ACTION_STARTED = "com.example.android.supportv4.STARTED";
	static final String ACTION_UPDATE = "com.example.android.supportv4.UPDATE";
	static final String ACTION_STOPPED = "com.example.android.supportv4.STOPPED";

	LocalBroadcastManager mLocalBroadcastManager;
	BroadcastReceiver mReceiver;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		setContentView(R.layout.main);

		// This is where we print the data we get back.
		final TextView callbackData = (TextView) findViewById(R.id.callback);

		// Put in some initial text.
		callbackData.setText("No broadcast received yet");

		// We use this to send broadcasts within our local process.
		mLocalBroadcastManager = LocalBroadcastManager.getInstance(this);

		// We are going to watch for interesting local broadcasts.
		IntentFilter filter = new IntentFilter();
		filter.addAction(ACTION_STARTED);
		filter.addAction(ACTION_UPDATE);
		filter.addAction(ACTION_STOPPED);
		mReceiver = new BroadcastReceiver() {
			@Override
			public void onReceive(Context context, Intent intent) {
				if (intent.getAction().equals(ACTION_STARTED)) {
					callbackData.setText("STARTED");
				} else if (intent.getAction().equals(ACTION_UPDATE)) {
					callbackData.setText("Got update: " + intent.getIntExtra("value", 0));
				} else if (intent.getAction().equals(ACTION_STOPPED)) {
					callbackData.setText("STOPPED");
				}
			}
		};
		mLocalBroadcastManager.registerReceiver(mReceiver, filter);

		// Watch for button clicks.
		Button button = (Button) findViewById(R.id.start);
		button.setOnClickListener(mStartListener);
		button = (Button) findViewById(R.id.stop);
		button.setOnClickListener(mStopListener);
	}

	@Override
	protected void onDestroy() {
		super.onDestroy();
		mLocalBroadcastManager.unregisterReceiver(mReceiver);
	}

	private OnClickListener mStartListener = new OnClickListener() {
		public void onClick(View v) {
			startService(new Intent(LocalServiceBroadcasterActivity.this, LocalService.class));
		}
	};

	private OnClickListener mStopListener = new OnClickListener() {
		public void onClick(View v) {
			stopService(new Intent(LocalServiceBroadcasterActivity.this, LocalService.class));
		}
	};

	public static class LocalService extends Service {
		LocalBroadcastManager mLocalBroadcastManager;
		int mCurUpdate;

		static final int MSG_UPDATE = 1;

		Handler mHandler = new Handler() {
			@Override
			public void handleMessage(Message msg) {
				switch (msg.what) {
				case MSG_UPDATE: {
					mCurUpdate++;
					Intent intent = new Intent(ACTION_UPDATE);
					intent.putExtra("value", mCurUpdate);
					mLocalBroadcastManager.sendBroadcast(intent);
					Message nmsg = mHandler.obtainMessage(MSG_UPDATE);
					mHandler.sendMessageDelayed(nmsg, 1000);
				}
					break;
				default:
					super.handleMessage(msg);
				}
			}
		};

		@Override
		public void onCreate() {
			super.onCreate();
			mLocalBroadcastManager = LocalBroadcastManager.getInstance(this);
		}

		public int onStartCommand(Intent intent, int flags, int startId) {
			// Tell any local interested parties about the start.
			mLocalBroadcastManager.sendBroadcast(new Intent(ACTION_STARTED));

			// Prepare to do update reports.
			mHandler.removeMessages(MSG_UPDATE);
			Message msg = mHandler.obtainMessage(MSG_UPDATE);
			mHandler.sendMessageDelayed(msg, 1000);
			return ServiceCompat.START_STICKY;
		}

		@Override
		public void onDestroy() {
			super.onDestroy();

			// Tell any local interested parties about the stop.
			mLocalBroadcastManager.sendBroadcast(new Intent(ACTION_STOPPED));

			// Stop doing updates.
			mHandler.removeMessages(MSG_UPDATE);
		}

		@Override
		public IBinder onBind(Intent intent) {
			return null;
		}
	}
}

main.xml布局文件:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:gravity="center_horizontal"
    android:orientation="vertical"
    android:padding="4dip" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="0"
        android:paddingBottom="4dip"
        android:text="演示如何使用LocalBroadcastManager来进行Service和Activity之间的通信" />

    <Button
        android:id="@+id/start"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="开启服务" >

        <requestFocus />
    </Button>

    <Button
        android:id="@+id/stop"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="停止服务" >
    </Button>

    <TextView
        android:id="@+id/callback"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="0"
        android:gravity="center_horizontal"
        android:paddingTop="4dip" />

</LinearLayout>

记得要加上android-support-v4.jar并加入classpath