.. java:import:: android.app Activity

.. java:import:: android.content Context

.. java:import:: android.content Intent

.. java:import:: com.idopte.scmiddleware Log

.. java:import:: androidx.annotation NonNull

.. java:import:: androidx.annotation Nullable

.. java:import:: androidx.appcompat.app AppCompatActivity

.. java:import:: androidx.lifecycle DefaultLifecycleObserver

.. java:import:: androidx.lifecycle LifecycleOwner

.. java:import:: com.idopte.cardsystem CardSystem

.. java:import:: com.idopte.scmapi SCMException

.. java:import:: com.idopte.scmiddleware SCWSSystem

.. java:import:: com.idopte.tools AppConfig

SCMHelper
=========

.. java:package:: com.idopte.scmapiembed
   :noindex:

.. java:type:: public class SCMHelper

   The \ ``SCMHelper``\  class manages several software components throughout the application activities lifecycle.

   This class should be used to enable NFC reader on activity resume or to save cache on activity pause for instance. \ ``SCMHelper``\  can be used in two different ways:

   ..

   * \ **standard way**\ : an \ ``Activity``\  is used through the methods \ :java:ref:`SCMHelper.activityCreated`\ , \ :java:ref:`SCMHelper.activityDestroyed`\ , \ :java:ref:`SCMHelper.activityPaused`\  and \ :java:ref:`SCMHelper.activityResumed`\ .
   * \ **automated way**\ : an \ ``androidx.appcompat.app.AppCompatActivity``\  is used through the methods \ :java:ref:`SCMHelper.observableActivityCreated`\  and, if needed, \ :java:ref:`SCMHelper.observableActivityDestroyed`\ . This is a convenient way since fewer methods are called and things are more automated but requires a \ ``AppCompatActivity``\  activity. In practice, this method is called in the ``onCreate`` method of an activity.

   These two ways to use \ ``SCMHelper``\  are equivalent, choice is up to the developer. Sample codes are given below.

   \ **Using an Activity activity:**\

   .. parsed-literal::

      public class MyActivity extends Activity {
          \@Override
          protected void onCreate(Bundle savedInstanceState) {
              super.onCreate(savedInstanceState);
              SCMHelper.activityCreated(this);
          }

          \@Override
          protected void onDestroy() {
              super.onDestroy();
              SCMHelper.activityDestroyed(this);
          }

          \@Override
          protected void onResume() {
              super.onResume();
              SCMHelper.activityResumed(this);
          }

          \@Override
          protected void onPause() {
              super.onPause();
              SCMHelper.activityPaused(this);
          }

          \@Override
          public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
              super.onRequestPermissionsResult(requestCode, permissions, grantResults);
              SCMHelper.onRequestPermissionsResult(requestCode, permissions, grantResults);
          }

          \@Override
          protected void onNewIntent(Intent intent) {
              super.onNewIntent(intent);
              SCMHelper.activityNewIntent(intent);
          }
      }

   \ **Using an AppCompatActivity activity:**\

   .. parsed-literal::

      public class MyActivity extends AppCompatActivity {
          \@Override
          protected void onCreate(Bundle savedInstanceState) {
              super.onCreate(savedInstanceState);
              SCMHelper.observableActivityCreated(this);
          }

          \@Override
          public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
              super.onRequestPermissionsResult(requestCode, permissions, grantResults);
              SCMHelper.onRequestPermissionsResult(requestCode, permissions, grantResults);
          }

          \@Override
          protected void onNewIntent(Intent intent) {
              super.onNewIntent(intent);
              SCMHelper.activityNewIntent(intent);
          }
      }

Methods
-------
activityCreated
^^^^^^^^^^^^^^^

.. java:method:: public static void activityCreated(Activity activity)
   :outertype: SCMHelper

   Initializes SCM backend and checks on user permissions. Starts listening to USB reader events and loads cache.

   This method must be called in Main Thread.

   :param activity: activity in which this method must be called, in \ ``Activity::onCreate``\ .

activityDestroyed
^^^^^^^^^^^^^^^^^

.. java:method:: public static void activityDestroyed(Activity activity)
   :outertype: SCMHelper

   Stops listening to USB reader events.

   :param activity: activity in which this method must be called, in \ ``Activity::onDestroy``\ .

activityNewIntent
^^^^^^^^^^^^^^^^^

.. java:method:: public static void activityNewIntent(Intent intent)
   :outertype: SCMHelper

   Looks for NFC TAG in activity intent.

   :param intent: the intent received by the activity.

activityPaused
^^^^^^^^^^^^^^

.. java:method:: public static void activityPaused(Activity activity)
   :outertype: SCMHelper

   Stops listening to BLE and NFC reader events, and saves cache.

   :param activity: activity in which this method must be called, in \ ``Activity::onPause``\ .

activityResumed
^^^^^^^^^^^^^^^

.. java:method:: public static void activityResumed(Activity activity)
   :outertype: SCMHelper

   Starts listening to BLE and NFC reader events.

   :param activity: activity in which this method must be called, in \ ``Activity::onResume``\ .

observableActivityCreated
^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: public static void observableActivityCreated(AppCompatActivity activity)
   :outertype: SCMHelper

   Starts to observe given activity lifecycle and initializes SCM backend.

   This method must be called in Main Thread.

   \ :java:ref:`SCMHelper.activityCreated`\ , \ :java:ref:`SCMHelper.activityDestroyed`\ , \ :java:ref:`SCMHelper.activityResumed`\  and \ :java:ref:`SCMHelper.activityPaused`\  are automatically called.

   :param activity: activity to observe.

observableActivityDestroyed
^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: public static void observableActivityDestroyed(AppCompatActivity activity)
   :outertype: SCMHelper

   Stops to observe given activity lifecycle.

   \ :java:ref:`SCMHelper.observableActivityCreated`\  is assumed to be previously called with same activity. This method is automatically called in given activity \ ``onDestroy``\  method.

   :param activity: activity to stop to observe.

onRequestPermissionsResult
^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: public static void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults)
   :outertype: SCMHelper

   Transmits request permissions result to the middleware.

   :param requestCode: the request code given by \ :java:ref:`Activity.onRequestPermissionsResult(int,String[],int[])`\  callback.
   :param permissions: the permissions given by \ :java:ref:`Activity.onRequestPermissionsResult(int,String[],int[])`\  callback.
   :param grantResults: the grantResults given by \ :java:ref:`Activity.onRequestPermissionsResult(int,String[],int[])`\  callback.