ESP8266WebServer - Refactoring class, problems with std::bind and handleRoot - c++

Question

I'm having some trouble while putting my ESP8266WebServer standard connection procedure to its own class. I'm not able to pass the object server to my handleRoot function via bind::std.... I have tried multiple approaches, but right now, nothing succeeds. So maybe you could help me. Right now, the code compiles, I have commented out the corresponding lines. But in order to peform some actions on a client request, I need to have access to the server class methods in the functions handleRoot and handleForm. Here are the corresponding sketches. Thank you for your help.
Arduino sketch:
#include "WiFiHandler.h"
#include <ESP8266WebServer.h>
ESP8266WebServer server(80);
WiFiHandler myWiFiHandler;
void setup(){
Serial.begin(115200);
myWiFiHandler.setupWiFi(server); // Setup WiFi
}
void loop(){
myWiFiHandler.clientHandler(server); //Handle client requests
}
Header file:
#ifndef WiFiHandler_h
#define WiFiHandler_h
#include <WiFiSetup.h>
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include "handleHTML.h"
class WiFiHandler
{
private:
WiFiSetup myWiFiSetup; // Create object myWiFiSetup
handleHTML myHTMLhandler; // Create object myHTMLHandler
char* _ssid;
char* _password;
void handleRoot();
void handleForm();
public:
WiFiHandler();
~WiFiHandler();
void setupWiFi(ESP8266WebServer&);
void clientHandler(ESP8266WebServer&);
};
#endif
Source file:
#include <WiFiSetup.h>
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include "handleHTML.h"
#include "Arduino.h"
#include "WiFiHandler.h"
WiFiHandler::WiFiHandler()
: _ssid(myWiFiSetup.ssid()), _password(myWiFiSetup.passcode())
{
}
WiFiHandler::~WiFiHandler(){/*Nothing to destruct*/}
void WiFiHandler::setupWiFi(ESP8266WebServer& server_)
{
WiFi.begin(_ssid, _password);
// Wait for connection
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print("Status: \n");
Serial.println(WiFi.status());
}
//If connection successful show IP address in serial monitor
Serial.print("Connected to ");
Serial.println(_ssid);
Serial.print("IP address: ");
Serial.println(WiFi.localIP()); //IP address assigned to your ESP
server_.on("/", std::bind(&WiFiHandler::handleRoot, this)); // Which routine to handle at root location
server_.on("/", std::bind(&WiFiHandler::handleForm, this)); // Form action is handled here
server_.begin(); //Start server
Serial.println("HTTP server started");
}
void WiFiHandler::handleRoot()
{
Serial.print("WiFi-Request received");
// server_.send(200, "text/html", myHTMLhandler.getHTML()); //Send web page
}
void WiFiHandler::handleForm()
{
// String buttonState = server.arg("State");
Serial.print("State: ");
// Serial.println(buttonState);
String s = "<a href='/'> Go Back </a>";
// server_.send(200, "text/html", s); //Send web page
}
void WiFiHandler::clientHandler(ESP8266WebServer& server_)
{
server_.handleClient();
}

Answer 1

Changing the callback finally did the job.
server_.on("/", [&]() { handleRoot(server_); });
server_.on("/action_page", [&]() { handleForm(server_); });
and the corresponding function:
void WiFiHandler::handleRoot(ESP8266WebServer& server_)
{
server_.send(200, "text/html", myHTMLhandler.getHTML()); //Send web page
}

Answer 2

I do it the following way, the principle works by the way also with async webserver:
class MY_WebServer : public WebServer { // inherit from the lib class
public:
MY_WebServer();
void begin() {
MDNS.addService("http", "tcp", 80);
WebServer::begin();
}
void startWebServer(); // this function initializes wifi, all handlers and params
private:
void handleFileList();
//.... some 30 handlers ...
}
Works in a quite complex application stable for months.