Android example source code file (ServiceStartArguments.java)

This example Android source code file (ServiceStartArguments.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

activity, android, app, application, button, controller, handlerthread, intent, message, notificationmanager, onclicklistener, os, override, pendingintent, re-delivered, servicehandler, servicestartarguments, start_flag_retry, ui, widget

The ServiceStartArguments.java Android example source code

/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.android.apis.app;

import android.app.Activity;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.IBinder;
import android.os.Looper;
import android.os.Message;
import android.os.Process;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

import com.example.android.apis.R;

/**
 * This is an example of implementing an application service that runs locally
 * in the same process as the application.  The {@link Controller}
 * class shows how to interact with the service. 
 *
 * <p>Notice the use of the {@link NotificationManager} when interesting things
 * happen in the service.  This is generally how background services should
 * interact with the user, rather than doing something more disruptive such as
 * calling startActivity().
 * 
 * <p>For applications targeting Android 1.5 or beyond, you may want consider
 * using the {@link android.app.IntentService} class, which takes care of all the
 * work of creating the extra thread and dispatching commands to it.
 */
public class ServiceStartArguments extends Service {
    private NotificationManager mNM;
    private Intent mInvokeIntent;
    private volatile Looper mServiceLooper;
    private volatile ServiceHandler mServiceHandler;
    
    private final class ServiceHandler extends Handler {
        public ServiceHandler(Looper looper) {
            super(looper);
        }
        
        @Override
        public void handleMessage(Message msg) {
            Bundle arguments = (Bundle)msg.obj;
        
            String txt = arguments.getString("name");
            
            Log.i("ServiceStartArguments", "Message: " + msg + ", "
                    + arguments.getString("name"));
        
            if ((msg.arg2&Service.START_FLAG_REDELIVERY) == 0) {
                txt = "New cmd #" + msg.arg1 + ": " + txt;
            } else {
                txt = "Re-delivered #" + msg.arg1 + ": " + txt;
            }
            
            showNotification(txt);
        
            // Normally we would do some work here...  for our sample, we will
            // just sleep for 5 seconds.
            long endTime = System.currentTimeMillis() + 5*1000;
            while (System.currentTimeMillis() < endTime) {
                synchronized (this) {
                    try {
                        wait(endTime - System.currentTimeMillis());
                    } catch (Exception e) {
                    }
                }
            }
        
            hideNotification();
            
            Log.i("ServiceStartArguments", "Done with #" + msg.arg1);
            stopSelf(msg.arg1);
        }

    };
    
    @Override
    public void onCreate() {
        mNM = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);

        Toast.makeText(this, R.string.service_created,
                Toast.LENGTH_SHORT).show();
        
        // This is who should be launched if the user selects our persistent
        // notification.
        mInvokeIntent = new Intent(this, Controller.class);

        // Start up the thread running the service.  Note that we create a
        // separate thread because the service normally runs in the process's
        // main thread, which we don't want to block.  We also make it
        // background priority so CPU-intensive work will not disrupt our UI.
        HandlerThread thread = new HandlerThread("ServiceStartArguments",
                Process.THREAD_PRIORITY_BACKGROUND);
        thread.start();
        
        mServiceLooper = thread.getLooper();
        mServiceHandler = new ServiceHandler(mServiceLooper);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.i("ServiceStartArguments",
                "Starting #" + startId + ": " + intent.getExtras());
        Message msg = mServiceHandler.obtainMessage();
        msg.arg1 = startId;
        msg.arg2 = flags;
        msg.obj = intent.getExtras();
        mServiceHandler.sendMessage(msg);
        Log.i("ServiceStartArguments", "Sending: " + msg);
        
        // For the start fail button, we will simulate the process dying
        // for some reason in onStartCommand().
        if (intent.getBooleanExtra("fail", false)) {
            // Don't do this if we are in a retry... the system will
            // eventually give up if we keep crashing.
            if ((flags&START_FLAG_RETRY) == 0) {
                // Since the process hasn't finished handling the command,
                // it will be restarted with the command again, regardless of
                // whether we return START_REDELIVER_INTENT.
                Process.killProcess(Process.myPid());
            }
        }
        
        // Normally we would consistently return one kind of result...
        // however, here we will select between these two, so you can see
        // how they impact the behavior.  Try killing the process while it
        // is in the middle of executing the different commands.
        return intent.getBooleanExtra("redeliver", false)
                ? START_REDELIVER_INTENT : START_NOT_STICKY;
    }

    @Override
    public void onDestroy() {
        mServiceLooper.quit();

        hideNotification();

        // Tell the user we stopped.
        Toast.makeText(ServiceStartArguments.this, R.string.service_destroyed,
                Toast.LENGTH_SHORT).show();
    }

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

    /**
     * Show a notification while this service is running.
     */
    private void showNotification(String text) {
        // Set the icon, scrolling text and timestamp
        Notification notification = new Notification(R.drawable.stat_sample, text,
                System.currentTimeMillis());

        // The PendingIntent to launch our activity if the user selects this notification
        PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
                new Intent(this, Controller.class), 0);

        // Set the info for the views that show in the notification panel.
        notification.setLatestEventInfo(this, getText(R.string.service_start_arguments_label),
                       text, contentIntent);

        // We show this for as long as our service is processing a command.
        notification.flags |= Notification.FLAG_ONGOING_EVENT;
        
        // Send the notification.
        // We use a string id because it is a unique number.  We use it later to cancel.
        mNM.notify(R.string.service_created, notification);
    }
    
    private void hideNotification() {
        mNM.cancel(R.string.service_created);
    }
    
    // ----------------------------------------------------------------------

    /**
     * Example of explicitly starting the {@link ServiceStartArguments}.
     * 
     * <p>Note that this is implemented as an inner class only keep the sample
     * all together; typically this code would appear in some separate class.
     */
    public static class Controller extends Activity {
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);

            setContentView(R.layout.service_start_arguments_controller);

            // Watch for button clicks.
            Button button = (Button)findViewById(R.id.start1);
            button.setOnClickListener(mStart1Listener);
            button = (Button)findViewById(R.id.start2);
            button.setOnClickListener(mStart2Listener);
            button = (Button)findViewById(R.id.start3);
            button.setOnClickListener(mStart3Listener);
            button = (Button)findViewById(R.id.startfail);
            button.setOnClickListener(mStartFailListener);
            button = (Button)findViewById(R.id.kill);
            button.setOnClickListener(mKillListener);
        }

        private OnClickListener mStart1Listener = new OnClickListener() {
            public void onClick(View v) {
                startService(new Intent(Controller.this,
                        ServiceStartArguments.class)
                                .putExtra("name", "One"));
            }
        };

        private OnClickListener mStart2Listener = new OnClickListener() {
            public void onClick(View v) {
                startService(new Intent(Controller.this,
                        ServiceStartArguments.class)
                                .putExtra("name", "Two"));
            }
        };

        private OnClickListener mStart3Listener = new OnClickListener() {
            public void onClick(View v) {
                startService(new Intent(Controller.this,
                        ServiceStartArguments.class)
                                .putExtra("name", "Three")
                                .putExtra("redeliver", true));
            }
        };

        private OnClickListener mStartFailListener = new OnClickListener() {
            public void onClick(View v) {
                startService(new Intent(Controller.this,
                        ServiceStartArguments.class)
                                .putExtra("name", "Failure")
                                .putExtra("fail", true));
            }
        };

        private OnClickListener mKillListener = new OnClickListener() {
            public void onClick(View v) {
                // This is to simulate the service being killed while it is
                // running in the background.
                Process.killProcess(Process.myPid());
            }
        };
    }
}