在Android中实现App Update功能

PackageManager packageManager = context.getPackageManager();
String packageName = context.getPackageName();
PackageInfo packageInfo = packageManager.getPackageInfo(packageName, 0);
int currentVersionCode = packageInfo.versionCode;

DownloadManager downloadManager = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
DownloadManager.Request request = new DownloadManager.Request(Uri.parse(apkUrl));
request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, "app_update.apk");
long downloadId = downloadManager.enqueue(request);

Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(apkFile), "application/vnd.android.package-archive");
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);