android中的更新功能实现

转自:Android apk更新，下载，安装
更新的思想一般都是从服务器获取到版本号,再和当前使用的app的版本号进行比较,如果不同,就进行提示更新;
activity中:

public class UpdateAppActivity extends BaseActivity {private  String url="http://192.168.56.1:8080/apk/AppName.apk";    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        requestWindowFeature(Window.FEATURE_NO_TITLE);        setContentView(R.layout.activity_update_app);        alertUpdate();    }    public void alertUpdate() {        AlertDialog.Builder alert = new AlertDialog.Builder(this);        alert.setTitle("软件升级").setMessage("发现新版本,建议立即更新使用.")                .setPositiveButton("更新", new DialogInterface.OnClickListener() {                    public void onClick(DialogInterface dialog, int which) {                        File file = new File(UpdateAppService.save_url + "/AppName.apk");                        if (file.exists()) {                            Uri uri = Uri.fromFile(file);                            Intent intent2 = new Intent(Intent.ACTION_VIEW);                            intent2.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);                            intent2.setDataAndType(uri, "application/vnd.android.package-archive");                            UpdateAppActivity.this.startActivity(intent2);                        } else {                            Intent intent = new Intent(UpdateAppActivity.this,                                    UpdateAppService.class);                            intent.putExtra("Key_App_Name", "AppName");                            intent.putExtra("Key_Down_Url", url);                            startService(intent);                        }                    }                }).setNegativeButton("取消", new DialogInterface.OnClickListener() {            public void onClick(DialogInterface dialog, int which) {                dialog.dismiss();            }        });        alert.create().show();    }}

在这里我们是用的是底层服务来进行下载,
service:

public class UpdateAppService extends Service{    private String app_name;// 文件名    private String down_url;// 下载文件地址    public static String save_url = Environment.getExternalStorageDirectory() + "/Louyx";    private static final int TIMEOUT = 10 * 1000;// 超时    private static final int DOWN_OK = 1;    private static final int DOWN_ERROR = 0;    // 通知    private NotificationManager notificationManager;    private Notification notification;    private RemoteViews contentView;    @Override    public IBinder onBind(Intent intent) {        return null;    }    @Override    public int onStartCommand(Intent intent, int flags, int startId) {        app_name = intent.getStringExtra("Key_App_Name");        down_url = intent.getStringExtra("Key_Down_Url");        if (FileUtils.createFile(save_url, app_name)) {            createNotification();            // 线程开启            new DownLoadThread().start();        }        else {            stopSelf();        }        return super.onStartCommand(intent, flags, startId);    }    public void createNotification() {        notification = new Notification(R.mipmap.ic_launcher, app_name + "正在下载",                System.currentTimeMillis());        notification.flags = Notification.FLAG_ONGOING_EVENT;        // 自定义 Notification 的显示        contentView = new RemoteViews(getPackageName(),R.layout.test_notification_item);        contentView.setTextViewText(R.id.notificationTitle, app_name + "正在下载");        contentView.setTextViewText(R.id.notificationPercent, "0%");        contentView.setProgressBar(R.id.notificationProgress, 100, 0, false);        notification.contentView = contentView;        notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);        notificationManager.notify(R.layout.test_notification_item, notification);    }    private class DownLoadThread extends Thread    {        @Override        public void run() {            Message message = new Message();            try {                long downloadSize = downloadUpdateFile(down_url, FileUtils.updateFile.toString());                if (downloadSize > 0) {                    message.what = DOWN_OK;                    handler.sendMessage(message);                }            } catch (Exception e) {                e.printStackTrace();                message.what = DOWN_ERROR;                handler.sendMessage(message);            }        }    }    public long downloadUpdateFile(String down_url, String file) throws Exception {        int totalSize; // 文件总大小        int downloadCount = 0; // 已经下载好的大小        int updateCount = 0; // 已经上传的文件大小        int downCount = 1;// 已下载好的百分比        InputStream inputStream=null;        OutputStream outputStream=null;        URL url = new URL(down_url);        HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();        url.openConnection();        httpURLConnection.setConnectTimeout(TIMEOUT);        httpURLConnection.setReadTimeout(TIMEOUT);        // 获取下载文件的总管大小size        totalSize = httpURLConnection.getContentLength();        if (httpURLConnection.getResponseCode() == 404) {            // 这个地方应该加一个下载失败的处理，但是，因为我们在外面加了一个try---catch，已经处理了Exception,所以不用处理            throw new Exception("fail!");        }        if(httpURLConnection.getResponseCode()==200){            inputStream = httpURLConnection.getInputStream();            outputStream = new FileOutputStream(file, false);// 文件存在则覆盖掉            byte buffer[] = new byte[1024];            int readsize = 0;            while ((readsize = inputStream.read(buffer)) != -1) {                outputStream.write(buffer, 0, readsize);                downloadCount += readsize;                int num = downloadCount * 100 / totalSize;                if (num > downCount || totalSize == downloadCount) {                    downCount = downloadCount * 100 / totalSize;                    // 改变通知栏                    contentView.setTextViewText(R.id.notificationPercent, downCount + "%");                    contentView.setProgressBar(R.id.notificationProgress, 100, downCount, false);                    notification.contentView = contentView;                    notificationManager.notify(R.layout.test_notification_item, notification);                }            }        }        if (httpURLConnection != null) {            httpURLConnection.disconnect();        }        inputStream.close();        outputStream.close();        return downloadCount;    }    private final Handler handler = new Handler() {        @Override        public void handleMessage(Message msg) {            switch (msg.what) {                case DOWN_OK:                    // 改变通知栏                    contentView.setTextViewText(R.id.notificationTitle, app_name + "下载完成");                    notification.contentView = contentView;                    notificationManager.notify(R.layout.test_notification_item, notification);                    //安装                    Uri uri = Uri.fromFile(FileUtils.updateFile);                    Intent intent = new Intent(Intent.ACTION_VIEW);                    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);                    intent.setDataAndType(uri, "application/vnd.android.package-archive");                    UpdateAppService.this.startActivity(intent);                    stopSelf();                    break;                case DOWN_ERROR:                    // 改变通知栏                    FileUtils.delFile(save_url + "/" + app_name + ".apk");                    contentView.setTextViewText(R.id.notificationTitle, app_name + "下载失败");                    notification.contentView = contentView;                    notificationManager.notify(R.layout.test_notification_item, notification);                    stopSelf();                    break;                default:                    break;            }        }    };}

一个简单地文件操作类:
FileUtils:

public class FileUtils {        public static File updateDir;        public static File updateFile;        public static boolean createFile(String url, String name) {            // 判断SD卡可读可写            if (android.os.Environment.MEDIA_MOUNTED.equals(android.os.Environment                    .getExternalStorageState())) {                updateDir = new File(url + "/");                updateFile = new File(url + "/" + name + ".apk");                if (!updateDir.exists()) {                    updateDir.mkdirs();                }                if (!updateFile.exists()) {                    try {                        updateFile.createNewFile();                    } catch (Exception e) {                        e.printStackTrace();                        return false;                    }                }                return true;            }            return false;        }        public static void delFile(String path) {            File file = new File(path);            if (file.exists()) {                file.delete();            }        }}

下载过程中的自定义通知栏布局文件:
test_notification_item

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"      android:layout_width="match_parent"    android:layout_height="match_parent">    <ImageView        android:id="@+id/notificationImage"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:src="@android:drawable/stat_sys_download"        android:paddingLeft="16dp"/>    <TextView        android:id="@+id/notificationTitle"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignParentRight="true"        android:layout_toRightOf="@id/notificationImage"        android:paddingLeft="26dp"        android:textColor="#FFFFFFFF" />    <!-- android:textColor="#FF000000"  -->    <TextView        android:id="@+id/notificationPercent"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_below="@id/notificationImage"        android:paddingTop="2dp"        android:textColor="#FFFFFFFF"        android:paddingLeft="16dp"/>    <ProgressBar        android:id="@+id/notificationProgress"        style="?android:attr/progressBarStyleHorizontal"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignLeft="@id/notificationTitle"        android:layout_alignParentRight="true"        android:layout_alignTop="@id/notificationPercent"        android:layout_below="@id/notificationTitle"        android:paddingLeft="26dp"        android:paddingRight="3dp"        android:paddingTop="2dp" /></RelativeLayout>