I am starting to write a library that needs to incorporate the painlessmesh library as its core function, essentially, a wrapper around it. I started putting it together but quickly hit a snag wrapping the painlessmesh lib. I know I am missing something in the declaration, just cant figure out what.
Any help would be great moving this on.

I have the following code:

myLib.h

#ifndef myLib_h
#define myLib_h

#include "Arduino.h"

   struct libNode{
   String deviceName;
   String nodeName;
   String Parameters;
    };

class myLib
{
  public:
    myLib(libNode node);
    //myLib(int node);
    void beginMesh(String meshPrefix, String meshPassword, int meshPort);
    void updateMesh();
  private:
    EscapeNode _node;
    void receivedCallback(uint32_t from, String &msg);
  //int _node;
};

#endif

and in my myLib.cpp

#include "Arduino.h"
#include "myLib.h"
#include "painlessMesh.h"
    
    Scheduler userScheduler;  // to control your personal task
    painlessMesh mesh;

// Constructor
myLib::myLib(EscapeNode thisNode)
{
    // Intialise the variable
    _node = thisNode; //{"testDevice", "TestNode", "Parameter JSON String"};
    
    // Start Up The Node
    Serial.begin(115200);
    //beginMesh();

}

void myLib::beginMesh(String MESH_PREFIX, String MESH_PASSWORD, int MESH_PORT) {
Serial.println('beginMesh');
Serial.println(MESH_PREFIX);
    Serial.println(MESH_PASSWORD);
    Serial.println(MESH_PORT);

      //mesh.setDebugMsgTypes( ERROR | MESH_STATUS | CONNECTION | SYNC | COMMUNICATION | GENERAL | MSG_TYPES | REMOTE ); // all types on
  mesh.setDebugMsgTypes(ERROR | STARTUP);  // set before init() so that you can see startup messages

  mesh.init(MESH_PREFIX, MESH_PASSWORD, &userScheduler, MESH_PORT);
  mesh.onReceive (&myLib::receivedCallback);
  //mesh.onNewConnection(&newConnectionCallback);
  //mesh.onChangedConnections(&changedConnectionCallback);
  //mesh.onNodeTimeAdjusted(&nodeTimeAdjustedCallback);

  //userScheduler.addTask(taskSendMessage);
  //taskSendMessage.enable();
    
}

I have a very simple test program:

#include <myLib.h>

void setup() {
  // put your setup code here, to run once:
  libNode node;
  node.deviceName = "TestDevice";
  node.nodeName = "TestNode";
  node.Parameters = "{XXXXX}";

  myLib thisNode = myLib(node);

#define MESH_PREFIX "xxxx"
#define MESH_PASSWORD "xxxx"
#define MESH_PORT 5555

  thisNode.beginMesh(MESH_PREFIX , MESH_PASSWORD , 5555);

}

void loop() {
  // put your main code here, to run repeatedly:

}

I get this error message when I try and compile:

d:UsersrichaDocumentsArduinolibrariesmyLibmyLib.cpp: In member function ‘void myLib::beginMesh(String, String, int)’:
d:UsersrichaDocumentsArduinolibrariesmyLibmyLib.cpp:39:51: error: no matching function for call to ‘painlessmesh::wifi::Mesh::onReceive(void (myLib::)(uint32_t, String&))’
mesh.onReceive (&myLib::receivedCallback);
^
In file included from d:UsersrichaDocumentsArduinolibrariesPainless_Meshsrc/painlessMeshSTA.h:6,
from d:UsersrichaDocumentsArduinolibrariesPainless_Meshsrc/painlessMesh.h:20,
from d:UsersrichaDocumentsArduinolibrariesmyLibmyLib.cpp:9:
d:UsersrichaDocumentsArduinolibrariesPainless_Meshsrc/painlessmesh/mesh.hpp:227:8: note: candidate: ‘void painlessmesh::Mesh::onReceive(painlessmesh::receivedCallback_t) [with T = painlessmesh::Connection; painlessmesh::receivedCallback_t = std::function<void(unsigned int, String&)>]’
void onReceive(receivedCallback_t onReceive) {
^~~~~~~~~
d:UsersrichaDocumentsArduinolibrariesPainless_Meshsrc/painlessmesh/mesh.hpp:227:8: note: no known conversion for argument 1 from ‘void (myLib::)(uint32_t, String&)’ {aka ‘void (myLib::*)(unsigned int, String&)’} to ‘painlessmesh::receivedCallback_t’ {aka ‘std::function<void(unsigned int, String&)>’}

exit status 1

Compilation error: exit status 1