#include <WiFi.h>
#include <PubSubClient.h>

#define PIN_BUTTON XX
int state_btn = HIGH;

const char* wifi_ssid = "xxxx";
const char* wifi_password = "xxxx";

void setup() {
  pinMode(PIN_BUTTON,INPUT_PULLUP);
  Serial.begin(9600); //starts serial monitor
  WiFi.mode(WIFI_STA);
  WiFi.begin(wifi_ssid, wifi_password);
  Serial.print("Connecting to WiFi.."); //writes the text on serial monitor
  while (WiFi.status() != WL_CONNECTED) {
    Serial.print('.');
    delay(1000);
  }
  Serial.println("");
  Serial.println(WiFi.localIP());
}

void loop() {
  // put your main code here, to run repeatedly:
int state_new = digitalRead(PIN_BUTTON);
if (state_btn && !state_new) {
Serial.println("pressed");
}
state_btn = state_new;
delay(1);
}