Updated to restore compatibility with Android V6 (removed use of Consumer for callbacks)

app/build.gradle

@@ -6,7 +6,7 @@ android {
 
     defaultConfig {
         applicationId "uk.org.openseizuredetector"
-        minSdkVersion 24
+        minSdkVersion 23
         targetSdkVersion 30
         multiDexEnabled true
     }

app/src/main/AndroidManifest.xml

@@ -3,7 +3,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     package="uk.org.openseizuredetector"
     android:versionCode="94"
-    android:versionName="4.0.0n">
+    android:versionName="4.0.0p">
     <!-- android:allowBackup="false" -->
     <uses-permission android:name="android.permission.BLUETOOTH" />
     <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />

app/src/main/java/uk/org/openseizuredetector/AuthenticateActivity.java

@@ -172,7 +172,9 @@ public class AuthenticateActivity extends AppCompatActivity {
                     String uname = mUnameEt.getText().toString();
                     String passwd = mPasswdEt.getText().toString();
                     Log.v(TAG,"onOK() - uname="+uname+", passwd="+passwd);
-                    mWac.authenticate(uname,passwd, (String retVal) -> {
+                    mWac.authenticate(uname, passwd, new WebApiConnection.StringCallback() {
+                        @Override
+                        public void accept(String retVal) {
                             if (retVal != null) {
                                 Log.d(TAG,"Authentication Success - token is "+retVal);
                                 mUtil.showToast("Login Successful");
@@ -183,6 +185,7 @@ public class AuthenticateActivity extends AppCompatActivity {
                                 mUtil.showToast("ERROR: Authentication Failed - Please Try Again");
                                 mUtil.writeToSysLogFile("AuthActivity - Authorisation failed for "+uname+", "+passwd);
                             }
+                        }
                     });
                     //finish();
                 }

app/src/main/java/uk/org/openseizuredetector/EditEventActivity.java

@@ -126,7 +126,9 @@ public class EditEventActivity extends AppCompatActivity {
         // Retrieve the JSONObject containing the standard event types.
         // Note this obscure syntax is to avoid having to create another interface, so it is worth it :)
         // See https://medium.com/@pra4mesh/callback-function-in-java-20fa48b27797
-        mWac.getEventTypes((JSONObject eventTypesObj) -> {
+        mWac.getEventTypes(new WebApiConnection.JSONObjectCallback() {
+            @Override
+            public void accept(JSONObject eventTypesObj) {
                 Log.v(TAG, "initialiseServiceConnection().onEventTypesReceived");
                 if (eventTypesObj == null) {
                     Log.e(TAG, "initialiseServiceConnection().getEventTypes Callback:  Error Retrieving event types");
@@ -153,11 +155,14 @@ public class EditEventActivity extends AppCompatActivity {
                     }
                     updateUi();
                 }
+            }
         });
 
         // Retrieve the event data to edit
         try {
-            mWac.getEvent(mEventId, (JSONObject eventObj) -> {
+            mWac.getEvent(mEventId, new WebApiConnection.JSONObjectCallback() {
+                @Override
+                public void accept(JSONObject eventObj) {
                     Log.v(TAG, "onCreate.getEvent");
                     if (eventObj != null) {
                         mEventObj = eventObj;
@@ -168,18 +173,14 @@ public class EditEventActivity extends AppCompatActivity {
                         mUtil.showToast("Failed to Retrieve Event from Remote Database");
                         finish();
                     }
+                }
             });
         } catch (Exception e) {
             Log.e(TAG, "ERROR:" + e.getMessage());
             e.printStackTrace();
         }
-
-
     }
 
-
-
-
     private void updateUi() {
         Log.v(TAG, "updateUI");
         TextView tv;
@@ -293,7 +294,9 @@ public class EditEventActivity extends AppCompatActivity {
 
 
                     try {
-                        mWac.updateEvent(mEventObj, (JSONObject eventObj) -> {
+                        mWac.updateEvent(mEventObj, new WebApiConnection.JSONObjectCallback() {
+                            @Override
+                            public void accept(JSONObject eventObj) {
                                 Log.v(TAG, "onOk.updateEvent");
                                 //mEventObj = eventObj;
                                 if (eventObj != null) {
@@ -306,19 +309,13 @@ public class EditEventActivity extends AppCompatActivity {
                                     updateUi();
                                 }
                             }
-                        );
+                        });
                     } catch (Exception e) {
                         Log.e(TAG,"ERROR:"+e.getMessage());
                         e.printStackTrace();
                         mUtil.showToast("Error Updating Event");
                         updateUi();
                     }
-
-                    //String uname = mUnameEt.getText().toString();
-                    //String passwd = mPasswdEt.getText().toString();
-                    //Log.v(TAG,"onOK() - uname="+uname+", passwd="+passwd);
-                    //mWac.authenticate(uname,passwd);
-                    //finish();
                 }
             };
 

app/src/main/java/uk/org/openseizuredetector/LogManager.java

@@ -45,7 +45,6 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Date;
 import java.util.HashMap;
-import java.util.function.Consumer;
 
 //import static android.database.sqlite.SQLiteDatabase.openOrCreateDatabase;
 
@@ -89,6 +88,13 @@ public class LogManager {
     private boolean mAutoPruneDb;
     private AutoPruneTimer mAutoPruneTimer;
 
+    public interface CursorCallback {
+        void accept(Cursor retVal);
+    }
+
+    public interface ArrayListCallback {
+        void accept(ArrayList<HashMap<String, String>> retVal);
+    }
 
     public LogManager(Context context,
                       boolean logRemote, boolean logRemoteMobile, String authToken,
@@ -312,7 +318,7 @@ public class LogManager {
      *
      * @return True on successful start or false if call fails.
      */
-    public boolean getDatapointsByDate(String startDateStr, String endDateStr, Consumer<String> callback) {
+    public boolean getDatapointsByDate(String startDateStr, String endDateStr, WebApiConnection.StringCallback callback) {
         Log.d(TAG, "getDatapointsbyDate() - startDateStr=" + startDateStr + ", endDateStr=" + endDateStr);
         String[] columns = {"*"};
         String whereClause = "DataTime>? AND DataTime<?";
@@ -336,7 +342,7 @@ public class LogManager {
      * @param includeWarnings - whether to include warnings in the list of events, or just alarm conditions.
      * @return True on successful start or false if call fails.
      */
-    public boolean getEventsList(boolean includeWarnings, Consumer<ArrayList<HashMap<String, String>>> callback) {
+    public boolean getEventsList(boolean includeWarnings, ArrayListCallback callback) {
         Log.v(TAG, "getEventsList - includeWarnings=" + includeWarnings);
         ArrayList<HashMap<String, String>> eventsList = new ArrayList<>();
 
@@ -399,7 +405,7 @@ public class LogManager {
      * @param includeWarnings - whether to include warnings in the list of events, or just alarm conditions.
      * @return True on successful start or false if call fails.
      */
-    public boolean getNextEventToUpload(boolean includeWarnings, Consumer<Long> callback) {
+    public boolean getNextEventToUpload(boolean includeWarnings, WebApiConnection.LongCallback callback) {
         Log.v(TAG, "getNextEventToUpload - includeWarnings=" + includeWarnings);
 
         String[] whereArgsStatus = getEventWhereArgs(includeWarnings);
@@ -448,7 +454,7 @@ public class LogManager {
      *
      * @return True on successful start or false if call fails.
      */
-    public boolean getNearestDatapointToDate(String dateStr, Consumer<Long> callback) {
+    public boolean getNearestDatapointToDate(String dateStr, WebApiConnection.LongCallback callback) {
         Log.v(TAG, "getNextEventToDate - dateStr=" + dateStr);
         String[] columns = {"*", "(julianday(dataTime)-julianday(datetime('" + dateStr + "'))) as ddiff"};
         //SQLStr = "SELECT *, (julianday(dataTime)-julianday(datetime('" + dateStr + "'))) as ddiff from " + mDbTableName + " order by ABS(ddiff) asc;";
@@ -481,7 +487,7 @@ public class LogManager {
      * @param includeWarnings - whether to include warnings in the list of events, or just alarm conditions.
      * @return True on successful start or false if call fails.
      */
-    public boolean getLocalEventsCount(boolean includeWarnings, Consumer<Long> callback) {
+    public boolean getLocalEventsCount(boolean includeWarnings, WebApiConnection.LongCallback callback) {
         Log.v(TAG, "getLocalEventsCount- includeWarnings=" + includeWarnings);
         String[] whereArgs = getEventWhereArgs(includeWarnings);
         String whereClause = getEventWhereClause(includeWarnings);
@@ -504,7 +510,7 @@ public class LogManager {
      *
      * @return True on successful start or false if call fails.
      */
-    public boolean getLocalDatapointsCount(Consumer<Long> callback) {
+    public boolean getLocalDatapointsCount(WebApiConnection.LongCallback callback) {
         Log.v(TAG, "getLocalDatapointsCount");
         String[] whereArgs = null;
         String whereClause = null;
@@ -537,12 +543,12 @@ public class LogManager {
         String mGroupBy;
         String mHaving;
         String mOrderBy;
-        Consumer<Cursor> mCallback;
+        CursorCallback mCallback;
 
         //query(String table, String[] columns, String selection, String[] selectionArgs,
         // String groupBy, String having, String orderBy)
         SelectQueryTask(String table, String[] columns, String selection, String[] selectionArgs,
-                        String groupBy, String having, String orderBy, Consumer<Cursor> callback) {
+                        String groupBy, String having, String orderBy, CursorCallback callback) {
             // list all the parameters like in normal class define
             this.mTable = table;
             this.mColumns = columns;

app/src/main/java/uk/org/openseizuredetector/SdServer.java

@@ -279,8 +279,6 @@ public class SdServer extends Service implements SdDataReceiver {
         mUtil.writeToSysLogFile("SdServer.onStartCommand() - starting SdDataSource");
         mSdDataSource.start();
 
-        checkEvents();
-
         // Initialise Notification channel for API level 26 and over
         // from https://stackoverflow.com/questions/44443690/notificationcompat-with-api-26
         mNM = (NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);
@@ -349,6 +347,8 @@ public class SdServer extends Service implements SdDataReceiver {
             mUtil.writeToSysLogFile("SdServer.onStartCommand() - mWakeLock is not null - this shouldn't happen???");
         }
 
+        checkEvents();
+
         return START_STICKY;
     }
 

app/src/main/java/uk/org/openseizuredetector/WebApiConnection.java

@@ -1,20 +1,15 @@
 package uk.org.openseizuredetector;
 
 import android.content.Context;
-import android.content.SharedPreferences;
-import android.icu.text.RelativeDateTimeFormatter;
 import android.os.Handler;
-import android.preference.PreferenceManager;
 import android.util.Log;
 
-
 import com.android.volley.AuthFailureError;
 import com.android.volley.Request;
 import com.android.volley.RequestQueue;
 import com.android.volley.Response;
 import com.android.volley.VolleyError;
 import com.android.volley.VolleyLog;
-import com.android.volley.toolbox.JsonObjectRequest;
 import com.android.volley.toolbox.StringRequest;
 import com.android.volley.toolbox.Volley;
 
@@ -24,12 +19,10 @@ import org.json.JSONObject;
 
 import java.io.UnsupportedEncodingException;
 import java.text.DateFormat;
-import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.Map;
-import java.util.function.Consumer;
 
 
 // This class is intended to handle all interactions with the OSD WebAPI
@@ -44,6 +37,18 @@ public class WebApiConnection {
     private OsdUtil mUtil;
     RequestQueue mQueue;
 
+    public interface JSONObjectCallback {
+        public void accept(JSONObject retValObj);
+    }
+
+    public interface StringCallback {
+        public void accept(String retValStr);
+    }
+
+    public interface LongCallback {
+        public void accept(Long retVal);
+    }
+
     public WebApiConnection(Context context) {
         mContext = context;
         mQueue = Volley.newRequestQueue(context);
@@ -64,7 +69,7 @@ public class WebApiConnection {
      * @param callback - call back function callback(String retVal)
      * @return true if request sent, or false if failed to send request.
      */
-    public boolean authenticate(final String uname, final String passwd, Consumer<String> callback) {
+    public boolean authenticate(final String uname, final String passwd, StringCallback callback) {
         // NOTE:  the 'final' keyword is necessary for uname and passwd to be accessible to getParams below - I don't know why!
         // We know that this command works, so we just need the Java equivalent:
         // curl -X POST -d 'login=graham4&password=testpwd1' https://osdapi.ddns.net/api/accounts/login/
@@ -148,7 +153,7 @@ public class WebApiConnection {
 
 
     // Create a new event in the remote database, based on the provided parameters.
-    public boolean createEvent(final int osdAlarmState, final Date eventDate, final String eventDesc, Consumer<String> callback) {
+    public boolean createEvent(final int osdAlarmState, final Date eventDate, final String eventDesc, StringCallback callback) {
         Log.v(TAG, "createEvent()");
         String urlStr = mUrlBase + "/api/events/";
         Log.v(TAG, "urlStr=" + urlStr);
@@ -227,7 +232,7 @@ public class WebApiConnection {
         return (true);
     }
 
-    public boolean getEvent(Long eventId, Consumer<JSONObject> callback) {
+    public boolean getEvent(Long eventId, JSONObjectCallback callback) {
         //Long eventId=Long.valueOf(285);
         Log.v(TAG, "getEvent()");
         String urlStr = mUrlBase + "/api/events/" + eventId;
@@ -287,7 +292,7 @@ public class WebApiConnection {
      * @param callback
      * @return true on success or false on failure to initiate the request.
      */
-    public boolean getEvents(Consumer<JSONObject> callback) {
+    public boolean getEvents(JSONObjectCallback callback) {
         //Long eventId=Long.valueOf(285);
         Log.v(TAG, "getEvents()");
         String urlStr = mUrlBase + "/api/events/";
@@ -348,7 +353,7 @@ public class WebApiConnection {
     }
 
 
-    public boolean updateEvent(final JSONObject eventObj, Consumer<JSONObject> callback) {
+    public boolean updateEvent(final JSONObject eventObj, JSONObjectCallback callback) {
         Long eventId;
         Log.v(TAG, "updateEvent()");
         final String authtoken = getStoredToken();
@@ -447,7 +452,7 @@ public class WebApiConnection {
     }
 
 
-    public boolean createDatapoint(JSONObject dataObj, int eventId, Consumer<String> callback) {
+    public boolean createDatapoint(JSONObject dataObj, int eventId, StringCallback callback) {
         Log.v(TAG, "createDatapoint()");
         // Create a new event in the remote database, based on the provided parameters.
         String urlStr = mUrlBase + "/api/datapoints/";
@@ -537,7 +542,7 @@ public class WebApiConnection {
      * @param callback - function to be called with a JSONObject as a parameter that contains the user profile data.
      * @return true if request sent successfully, or else false.
      */
-    public boolean getUserProfile(Consumer<JSONObject> callback) {
+    public boolean getUserProfile(JSONObjectCallback callback) {
         Log.v(TAG, "getUserProfile()");
         String urlStr = mUrlBase + "/api/accounts/profile/";
         Log.v(TAG, "getUserProfile(): urlStr=" + urlStr);
@@ -595,12 +600,10 @@ public class WebApiConnection {
     /**
      * Retrieve the file containing the standard event types from the server.
      * Calls the specified callback function, passing a JSONObject as a parameter when the data has been received and parsed.
-     * Note it uses a Consumer callback function to avoid having to create another interface
-     * - see https://medium.com/@pra4mesh/callback-function-in-java-20fa48b27797
      *
      * @return true if request sent successfully or else false.
      */
-    public boolean getEventTypes(Consumer<JSONObject> callback) {
+    public boolean getEventTypes(JSONObjectCallback callback) {
         Log.v(TAG, "getEventTypes()");
         String urlStr = mUrlBase + "/static/eventTypes.json";
         Log.v(TAG, "urlStr=" + urlStr);