Address @paul-szczepanek-arm's comments

features/nfc/nfc/NFCControllerDriver.h

@@ -82,13 +82,14 @@ public:
      * @param[in] delegate the delegate instance to use
      */
     void set_delegate(Delegate *delegate);
-protected:
 
+protected:
     /**
      * An implementation must call this function (can be called from interrupt context)
      * when the controller asserts its interrupt line
      */
     void hw_interrupt();
+
 private:
     Delegate *_delegate;
 };

features/nfc/nfc/NFCEEPROM.h

@@ -119,6 +119,9 @@ private:
     void continue_read();
     void continue_erase();
 
+    // NFCNDEFCapable implementation
+    virtual NFCNDEFCapable::Delegate *ndef_capable_delegate();
+
     enum nfc_eeprom_operation_t {
         nfc_eeprom_idle,
 

features/nfc/nfc/NFCNDEFCapable.h

@@ -81,13 +81,6 @@ public:
         ~Delegate() {}
     };
 
-    /**
-     * Set the delegate that will receive events generated by this class.
-     *
-     * @param[in] delegate the delegate instance to use
-     */
-    void set_ndef_delegate(Delegate *delegate);
-
 protected:
     /**
      * Parse a NDEF message.
@@ -111,13 +104,19 @@ protected:
     ndef_msg_t *ndef_message();
 
 private:
+    /**
+     * Get the delegate that will receive events generated by this class.
+     *
+     * @return the delegate instance to use
+     */
+    virtual Delegate *ndef_capable_delegate();
+
     // Callbacks from NDEF stack
     static nfc_err_t s_ndef_encode(ndef_msg_t *pTag, ac_buffer_builder_t *pBufferBldr, void *pUserData);
     static nfc_err_t s_ndef_decode(ndef_msg_t *pTag, ac_buffer_t *pBuffer, void *pUserData);
     nfc_err_t ndef_encode(ac_buffer_builder_t *pBufferBldr);
     nfc_err_t ndef_decode(ac_buffer_t *pBuffer);
 
-    Delegate *_delegate;
     ndef_msg_t _ndef_message;
 };
 

features/nfc/nfc/NFCRemoteInitiator.h

@@ -92,6 +92,9 @@ protected:
     virtual void disconnected();
 
 private:
+    // NFCNDEFCapable implementation
+    virtual NFCNDEFCapable::Delegate *ndef_capable_delegate();
+
     Delegate *_delegate;
 };
 

features/nfc/source/nfc/NFCEEPROM.cpp

@@ -40,7 +40,6 @@ nfc_err_t NFCEEPROM::initialize()
 void NFCEEPROM::set_delegate(NFCEEPROM::Delegate *delegate)
 {
     _delegate = delegate;
-    set_ndef_delegate(delegate);
 }
 
 void NFCEEPROM::write_ndef_message()
@@ -419,3 +418,8 @@ void NFCEEPROM::handle_error(nfc_err_t ret)
         }
     }
 }
+
+NFCNDEFCapable::Delegate *NFCEEPROM::ndef_capable_delegate()
+{
+    return _delegate;
+}

features/nfc/source/nfc/NFCNDEFCapable.cpp

@@ -25,29 +25,27 @@
 using namespace mbed;
 using namespace mbed::nfc;
 
-NFCNDEFCapable::NFCNDEFCapable(const Span<uint8_t> &buffer) : _delegate(NULL)
+NFCNDEFCapable::NFCNDEFCapable(const Span<uint8_t> &buffer)
 {
     ndef_msg_init(&_ndef_message, s_ndef_encode, s_ndef_decode, buffer.data(), buffer.size(), this);
 }
 
-void NFCNDEFCapable::set_ndef_delegate(NFCNDEFCapable::Delegate *delegate)
-{
-    _delegate = delegate;
-}
-
 void NFCNDEFCapable::parse_ndef_message(const ac_buffer_t &buffer)
 {
     ac_buffer_t reader;
     ac_buffer_dup(&reader, &buffer);
-    if (_delegate != NULL) {
+
-        _delegate->parse_ndef_message(make_const_Span(ac_buffer_reader_current_buffer_pointer(&reader), ac_buffer_reader_current_buffer_length(&reader)));
+    Delegate *delegate = ndef_capable_delegate();
+    if (delegate != NULL) {
+        delegate->parse_ndef_message(make_const_Span(ac_buffer_reader_current_buffer_pointer(&reader), ac_buffer_reader_current_buffer_length(&reader)));
     }
 }
 
 void NFCNDEFCapable::build_ndef_message(ac_buffer_builder_t &buffer_builder)
 {
-    if (_delegate != NULL) {
+    Delegate *delegate = ndef_capable_delegate();
-        size_t count = _delegate->build_ndef_message(make_Span(ac_buffer_builder_write_position(&buffer_builder), ac_buffer_builder_writable(&buffer_builder)));
+    if (delegate != NULL) {
+        size_t count = delegate->build_ndef_message(make_Span(ac_buffer_builder_write_position(&buffer_builder), ac_buffer_builder_writable(&buffer_builder)));
         ac_buffer_builder_write_n_skip(&buffer_builder, count);
     }
 }
@@ -80,3 +78,8 @@ ndef_msg_t *NFCNDEFCapable::ndef_message()
 {
     return &_ndef_message;
 }
+
+NFCNDEFCapable::Delegate *NFCNDEFCapable::ndef_capable_delegate()
+{
+    return NULL;
+}

features/nfc/source/nfc/NFCRemoteInitiator.cpp

@@ -20,7 +20,7 @@ using namespace mbed;
 using namespace mbed::nfc;
 
 NFCRemoteInitiator::NFCRemoteInitiator(NFCController *controller, const Span<uint8_t> &buffer) :
-    NFCRemoteEndpoint(controller), NFCNDEFCapable(buffer)
+    NFCRemoteEndpoint(controller), NFCNDEFCapable(buffer), _delegate(NULL)
 {
 
 }
@@ -33,7 +33,6 @@ NFCRemoteInitiator::~NFCRemoteInitiator()
 void NFCRemoteInitiator::set_delegate(Delegate *delegate)
 {
     _delegate = delegate;
-    set_ndef_delegate(delegate);
 }
 
 void NFCRemoteInitiator::connected()
@@ -49,3 +48,8 @@ void NFCRemoteInitiator::disconnected()
         _delegate->on_disconnected();
     }
 }
+
+NFCNDEFCapable::Delegate *NFCRemoteInitiator::ndef_capable_delegate()
+{
+    return _delegate;
+}