Android如何实现APP自动更新

import android.app.Notification;import android.app.NotificationManager;import android.app.PendingIntent;import android.app.Service;import android.content.Intent;import android.graphics.BitmapFactory;import android.net.Uri;import android.os.IBinder;import android.support.annotation.Nullable;import android.support.v7.app.NotificationCompat;import com.fangku.commonlibrary.utils.StorageUtil;import com.zhy.http.okhttp.OkHttpUtils;import com.zhy.http.okhttp.callback.FileCallBack;import java.io.File;import okhttp3.Call;/** * 自动下载更新apk服务 * Create by: chenwei.li * Date: 2016-08-14 * time: 09:50 * Email: lichenwei.me@foxmail.com */public class DownloadService extends Service { private String mDownloadUrl;//APK的下载路径 private NotificationManager mNotificationManager; private Notification mNotification; @Override public void onCreate() { super.onCreate(); mNotificationManager = (NotificationManager) getSystemService(Service.NOTIFICATION_SERVICE); } @Override public int onStartCommand(Intent intent, int flags, int startId) { if (intent == null) {  notifyMsg("温馨提醒", "文件下载失败", 0);  stopSelf(); } mDownloadUrl = intent.getStringExtra("apkUrl");//获取下载APK的链接 downloadFile(mDownloadUrl);//下载APK return super.onStartCommand(intent, flags, startId); } @Nullable @Override public IBinder onBind(Intent intent) { return null; } private void notifyMsg(String title, String content, int progress) { NotificationCompat.Builder builder = new NotificationCompat.Builder(this);//为了向下兼容，这里采用了v7包下的NotificationCompat来构造 builder.setSmallIcon(R.mipmap.icon_login_logo).setLargeIcon(BitmapFactory.decodeResource(getResources(), R.mipmap.icon_login_logo)).setContentTitle(title); if (progress > 0 && progress < 100) {  //下载进行中  builder.setProgress(100, progress, false); } else {  builder.setProgress(0, 0, false); } builder.setAutoCancel(true); builder.setWhen(System.currentTimeMillis()); builder.setContentText(content); if (progress >= 100) {  //下载完成  builder.setContentIntent(getInstallIntent()); } mNotification = builder.build(); mNotificationManager.notify(0, mNotification); } /** * 安装apk文件 * * @return */ private PendingIntent getInstallIntent() { File file = new File(StorageUtil.DOWNLOAD_DIR + "APP文件名"); Intent intent = new Intent(Intent.ACTION_VIEW); intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); intent.setDataAndType(Uri.parse("file://" + file.getAbsolutePath()), "application/vnd.android.package-archive"); PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT); return pendingIntent; } /** * 下载apk文件 * * @param url */ private void downloadFile(String url) { OkHttpUtils.get().url(url).build().execute(new FileCallBack(StorageUtil.DOWNLOAD_DIR, "APP文件名") {  @Override  public void onError(Call call, Exception e, int id) {  notifyMsg("温馨提醒", "文件下载失败", 0);  stopSelf();  }  @Override  public void onResponse(File response, int id) {  //当文件下载完成后回调  notifyMsg("温馨提醒", "文件下载已完成", 100);  stopSelf();  }  @Override  public void inProgress(float progress, long total, int id) {  //progress*100为当前文件下载进度，total为文件大小  if ((int) (progress * 100) % 10 == 0) {   //避免频繁刷新View，这里设置每下载10%提醒更新一次进度   notifyMsg("温馨提醒", "文件正在下载..", (int) (progress * 100));  }  } }); }}

Intent intent = new Intent(mContext, DownloadService.class);intent.putExtra("apkUrl", "APK下载地址");startService(intent);