Make onRecieve also optional and make constructor protected

Author: P-R-O-C-H-Y

Diff for: docs/en/api/espnow.rst

@@ -234,7 +234,7 @@ Set the local master key (LMK) for the peer.
 onReceive
 ^^^^^^^^^^
 
-Callback function to handle incoming data from the peer. This is a pure virtual method that must be implemented by the upper class.
+Callback function to handle incoming data from the peer. This is a virtual method can be implemented by the upper class for custom handling.
 
 .. code-block:: cpp
 
@@ -247,7 +247,7 @@ Callback function to handle incoming data from the peer. This is a pure virtual
 onSent
 ^^^^^^^
 
-Optional callback function to handle the completion of sending data to the peer. This is a pure virtual method that must be implemented by the upper class.
+Callback function to handle the completion of sending data to the peer. This is a virtual method can be implemented by the upper class for custom handling.
 
 .. code-block:: cpp
 

Diff for: libraries/ESP_NOW/examples/ESP_NOW_Broadcast_Master/ESP_NOW_Broadcast_Master.ino

@@ -22,7 +22,7 @@
 
 /* Classes */
 
-// Create a new class that inherits from the ESP_NOW_Peer class is required to implement the _onReceive and _onSent methods.
+// Creating a new class that inherits from the ESP_NOW_Peer class is required.
 
 class ESP_NOW_Broadcast_Peer : public ESP_NOW_Peer {
 public:
@@ -52,12 +52,6 @@ public:
         }
         return true;
     }
-
-    void onReceive(const uint8_t *data, size_t len, bool broadcast) {
-        // The broadcast peer will never receive any data. Rather, it will only send data.
-        // Data broadcasted will be received by the actual object of the peer that made the broadcast.
-        // It is still required to be implemented because it is a pure virtual method.
-    }
 };
 
 /* Global Variables */

Diff for: libraries/ESP_NOW/examples/ESP_NOW_Broadcast_Slave/ESP_NOW_Broadcast_Slave.ino

@@ -23,7 +23,7 @@
 
 /* Classes */
 
-// Create a new class that inherits from the ESP_NOW_Peer class is required to implement the _onReceive and _onSent methods.
+// Creating a new class that inherits from the ESP_NOW_Peer class is required.
 
 class ESP_NOW_Peer_Class : public ESP_NOW_Peer {
 public:
@@ -50,11 +50,6 @@ public:
         Serial.printf("Received a message from master " MACSTR " (%s)\n", MAC2STR(addr()), broadcast ? "broadcast" : "unicast");
         Serial.printf("  Message: %s\n", (char *)data);
     }
-
-    void _onSent(bool success) {
-        // In this example the slave will never send any data, so this method will never be called.
-        // It is still required to be implemented because it is a pure virtual method.
-    }
 };
 
 /* Global Variables */

Diff for: libraries/ESP_NOW/examples/ESP_NOW_Network/ESP_NOW_Network.ino

@@ -98,7 +98,7 @@ std::vector<uint32_t> last_data(5);  // Vector that will store the last 5 data r
 
 /* Classes */
 
-// We need to create a class that inherits from ESP_NOW_Peer to implement the _onReceive and _onSent methods.
+// We need to create a class that inherits from ESP_NOW_Peer and implement the _onReceive and _onSent methods.
 // This class will be used to store the priority of the device and to send messages to the peers.
 // For more information about the ESP_NOW_Peer class, see the ESP_NOW_Peer class in the ESP32_NOW.h file.
 

Diff for: libraries/ESP_NOW/src/ESP32_NOW.cpp

@@ -2,7 +2,6 @@
 #include <string.h>
 #include "esp_system.h"
 #include "esp32-hal.h"
-#include "esp_mac.h"
 #include "esp_wifi.h"
 
 static void (*new_cb)(const esp_now_recv_info_t *info, const uint8_t * data, int len, void * arg) = NULL;

Diff for: libraries/ESP_NOW/src/ESP32_NOW.h

@@ -4,6 +4,7 @@
 #include "Print.h"
 #include "esp_now.h"
 #include "esp32-hal-log.h"
+#include "esp_mac.h"
 
 class ESP_NOW_Peer {
 private:
@@ -19,8 +20,9 @@ class ESP_NOW_Peer {
   bool remove();
   size_t send(const uint8_t * data, int len);
 
-public:
   ESP_NOW_Peer(const uint8_t *mac_addr, uint8_t channel=0, wifi_interface_t iface=WIFI_IF_AP, const uint8_t *lmk=NULL);
+
+public:
   virtual ~ESP_NOW_Peer() {}
 
   const uint8_t * addr() const;
@@ -37,11 +39,11 @@ class ESP_NOW_Peer {
 
   operator bool() const;
 
-  //must be implemented by the upper class
-  virtual void onReceive(const uint8_t * data, size_t len, bool broadcast) = 0;
-
-  //optional callback
-  virtual void onSent(bool success) { log_v("Message reported as sent %s", success ? "successfully" : "unsuccessfully"); }
+  //optional callbacks to be implemented by the upper class
+  virtual void onReceive(const uint8_t * data, size_t len, bool broadcast) {
+    log_i("Received %d bytes from " MACSTR " %s", len, MAC2STR(mac), broadcast ? "broadcast" : "");
+  }
+  virtual void onSent(bool success) { log_i("Message reported as sent %s", success ? "successfully" : "unsuccessfully"); }
 };
 
 class ESP_NOW_Class : public Print {