如何在android中实现应用内更新？

Question

我已经在Android中实现了新出现的功能，这些功能是使用Flexible进行的应用内更新。我已经引用了官方链接，但在应用下载完成后，我仍然遇到一些问题。

AppUpdateManager appUpdateManager;
    private void checkAppUpdateAvailability()
    {
        appUpdateManager = AppUpdateManagerFactory.create(this);
        Task<AppUpdateInfo> appUpdateInfoTask = appUpdateManager.getAppUpdateInfo();
        appUpdateInfoTask.addOnSuccessListener(new OnSuccessListener<AppUpdateInfo>() {
            @Override
            public void onSuccess(AppUpdateInfo appUpdateInfo) {
                if (appUpdateInfo.updateAvailability() == UpdateAvailability.UPDATE_AVAILABLE
                        // For a flexible update, use AppUpdateType.FLEXIBLE
                        && appUpdateInfo.isUpdateTypeAllowed(FLEXIBLE)) {
                    // Request the update.

                    try {
                        appUpdateManager.startUpdateFlowForResult(
                                // Pass the intent that is returned by 'getAppUpdateInfo()'.
                                appUpdateInfo,
                                // Or 'AppUpdateType.FLEXIBLE' for flexible updates.
                                FLEXIBLE,
                                // The current activity making the update request.
                                MainActivity.this,
                                // Include a request code to later monitor this update request.
                                100);
                    } catch (IntentSender.SendIntentException e) {
                        e.printStackTrace();
                    }

                }
            }
        });

    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == 100) {
            if (resultCode != RESULT_OK) {
                Log.d("JNiS","Update flow failed! Result code: " + resultCode);
                // If the update is cancelled or fails,
                // you can request to start the update again.
            }
        }
    }