Readability & layout

src/app/src/main/java/com/xfarrow/locatemydevice/WhitelistContactsActivity.java

@@ -108,7 +108,8 @@ public class WhitelistContactsActivity extends AppCompatActivity {
     private void contactSelected(String phoneNo){
         // We'll replace parenthesis, dashes and whitespaces to obtain a valid phone number
         phoneNo = phoneNo.replaceAll("[-()\\s]", "");
-        if(whitelistDbHandler.isContactPresent(phoneNo)){
+
+        if(contacts.contains(phoneNo)){
             Toast.makeText(this, "Contact already in the list", Toast.LENGTH_SHORT).show();
             return;
         }

src/app/src/main/java/com/xfarrow/locatemydevice/WhitelistDbHandler.java

@@ -54,11 +54,10 @@ public class WhitelistDbHandler extends SQLiteOpenHelper {
     }
 
     public ArrayList<String> getAllContacts() {
-        ArrayList<String> array_list = new ArrayList<String>();
-
-        //hp = new HashMap();
+        ArrayList<String> array_list = new ArrayList<>();
         SQLiteDatabase db = this.getReadableDatabase();
-        Cursor cursor =  db.rawQuery( "select * from " + TABLE_CONTACTS, null );
+        String query = String.format("SELECT %s FROM %s", KEY_PH_NO, TABLE_CONTACTS);
+        Cursor cursor =  db.rawQuery( query, null );
         cursor.moveToFirst();
 
         int columnIndex = cursor.getColumnIndex(KEY_PH_NO);
@@ -102,5 +101,4 @@ public class WhitelistDbHandler extends SQLiteOpenHelper {
         cursor.close();
         return count > 0;
     }
-
 }

src/app/src/main/res/layout/settings.xml

@@ -100,7 +100,7 @@
                 android:layout_height="wrap_content"
                 android:layout_marginStart="10dp"
                 android:layout_marginEnd="10dp"
-                android:text="Add contacts"/>
+                android:text="Whitelist contacts"/>
 
             <View
                 android:layout_width="match_parent"