一、需求分析
1、查询线上版本号，然后拿本地版本号与之对比。2、若线上版本号比本地版本号大，则下载线上版本号。3、把下载好的版本号安装，并替换当前旧版本
二、权限
根据上面的需求我们可以知道，需要用到的权限应该有网络权限、本地文件写入权限，本地文件读取权限。使用网络权限去获取线上的版本号，然后下载保存到本地，安装的时候再去本地取来。另外8.0上google把未知应用的安装权限的管理放到了每个app上，每个app都有允许安装未知应用的设置开关，所以这里也需要权限
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE">
<uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES"/>---8.0安装权限
复制代码三、步骤
1.先判断8.0以上的需要检测是否有权限，有的直接去检测版本更新，没有去申请
if (!checkInstall()){if (conn) {this.checkUpdate(splashView);} else {Toast.makeText(this, "请检查网络～", Toast.LENGTH_LONG).show();}}/*** 如果想让应用自动安装下载的新版本apk，那么必须打开应用的这个权限，不然是不会自动安装的*/public boolean checkInstall() {boolean haveInstallPermission;if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {//先获取是否有安装未知来源应用的权限haveInstallPermission = getPackageManager().canRequestPackageInstalls();if (!haveInstallPermission) {//没有权限android.support.v7.app.AlertDialog alertDialog = new android.support.v7.app.AlertDialog.Builder(this).setTitle("请开启未知来源权限").setMessage("应用需要打开安装未知来源应用权限，请去设置中开启权限").setCancelable(false).setNegativeButton("取消",new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {dialog.dismiss();Toast.makeText(WelcomeActivity.this, "您拒绝了权限，应用无法正常使用！", Toast.LENGTH_SHORT).show();finish();}}).setPositiveButton("去设置", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {dialog.dismiss();toInStallPermissionSettingActivity();}}).create();alertDialog.show();return true;}}return false;}@RequiresApi(api = Build.VERSION_CODES.O)private void toInStallPermissionSettingActivity() {Uri packageURI = Uri.parse("package:" + getPackageName());//注意这个是8.0新APIIntent intent = new Intent(Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES, packageURI);startActivityForResult(intent, REQUEST_CODE_INSTALL_PERMISSION);}@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {super.onActivityResult(requestCode, resultCode, data);if (resultCode==RESULT_OK&&requestCode==REQUEST_CODE_INSTALL_PERMISSION){if (conn) {this.checkUpdate(splashView);} else {Toast.makeText(this, "请检查网络～", Toast.LENGTH_LONG).show();}}else {finish();Toast.makeText(WelcomeActivity.this, " 您拒绝了权限，应用无法正常使用！", Toast.LENGTH_SHORT).show();}}
复制代码2网络请求检测更新
/*** 检测软件更新*/public void checkUpdate(final View splashView) {// 创建okHttpClient对象OkHttpClient mOkHttpClient = new OkHttpClient();Request request = new Request.Builder().url(Urls.UPDATEXML).build();//http://ushevapp-10060464.cos.myqcloud.com/version.xmlmOkHttpClient.newCall(request).enqueue(new okhttp3.Callback() {@Overridepublic void onFailure(okhttp3.Call call, IOException e) {Message msg = new Message();msg.what = 0;mmHandler.sendMessage(msg);Log.d("h_bl", "失败");}@Overridepublic void onResponse(okhttp3.Call call, okhttp3.Response response) throws IOException {InputStream is = null;byte[] buf = new byte[2048];int len = 0;String SDPath = Environment.getExternalStorageDirectory().getAbsolutePath();try {is = response.body().byteStream();ParseXmlService pxs = new ParseXmlService();stringStringHashMap = pxs.parseXml(is);Message msg = new Message();msg.what = 1;mmHandler.sendMessage(msg);Log.d("h_bl", "检测软件更新文件下载成功");} catch (Exception e) {Message msg = new Message();msg.what = 0;mmHandler.sendMessage(msg);Log.d("h_bl", "文检测软件更新件下载失败");} finally {try {if (is != null) {is.close();}} catch (IOException e) {}}}});
复制代码3、去开启服务下载apk，然后安装
/*** 下载文件:Okhttp*/private void loadFileByOkhttp() {initNotification();OkHttpClient mOkHttpClient = new OkHttpClient();Request request = new Request.Builder().url(url)
// .addHeader("Accept-Encoding", "identity").build();mOkHttpClient.newCall(request).enqueue(new Callback() {@Overridepublic void onFailure(okhttp3.Call call, IOException e) {cancelNotification();Log.d("h_bl", "新版本下载失败");}@Overridepublic void onResponse(okhttp3.Call call, Response response) throws IOException {InputStream is = null;byte[] buf = new byte[2048];int len = 0;FileOutputStream fos = null;try {is = response.body().byteStream();long total = response.body().contentLength();File file = new File(destFileDir, destFileName);fos = new FileOutputStream(file);long sum = 0;int progress = 0;while ((len = is.read(buf)) != -1) {fos.write(buf, 0, len);sum += len;progress = (int) (sum * 1.0f / total * 100);updateNotification(progress);}if (progress == 100) {cancelNotification();installApk(file);}fos.flush();Log.d("h_bl", "apk文件下载成功");} catch (Exception e) {e.printStackTrace();} finally {try {if (is != null) {is.close();}} catch (IOException e) {e.printStackTrace();}try {if (fos != null) {fos.close();}} catch (IOException e) {e.printStackTrace();}}}});}
复制代码另外这里也有8·0的坑，就是不做特殊处理下载没有通知显示，那么看代码
/*** 初始化Notification通知*/public void initNotification() {destFileDir = getTempDirectoryPath();notificationManager = (NotificationManager) mContext.getSystemService(Context.NOTIFICATION_SERVICE);if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {builder = new NotificationCompat.Builder(mContext, PUSH_CHANNEL_ID);NotificationChannel channel = new NotificationChannel(PUSH_CHANNEL_ID, PUSH_CHANNEL_NAME, NotificationManager.IMPORTANCE_HIGH);channel.enableVibration(false);channel.setVibrationPattern(new long[]{0});channel.setSound(null, null);if (notificationManager != null) {notificationManager.createNotificationChannel(channel);}builder.setSmallIcon(R.mipmap.logo).setContentText("0%").setContentTitle("住保服务更新").setChannelId(PUSH_CHANNEL_ID);} else {builder = new NotificationCompat.Builder(mContext).setSmallIcon(R.mipmap.logo).setContentText("0%").setContentTitle("住保服务更新");}notificationManager.notify(NOTIFY_ID, builder.build());}
复制代码最后安装apk，注意一些细节，更新的包需要和旧包有相同的签名文件否则会安装失败，还有就是8.0的坑了，前面以后给出权限解决
/*** 安装软件** @param file*/private void installApk(File file) {Uri uri = Uri.fromFile(file);Intent install = new Intent(Intent.ACTION_VIEW);install.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);install.setDataAndType(uri, "application/vnd.android.package-archive");// 执行意图进行安装mContext.startActivity(install);}复制代码欧了，现在应该自动更新没问题可以解决了，如有问题欢迎指正，互相学习
