This is my updated code to display the temperature and humidity in nextion display and also to control the relay switching in nextion display. It works good.

#include "NexDualStateButton.h" #include "Nextion.h" #include "DHT.h"

#define DHTPIN 27 #define DHTTYPE DHT22

DHT dht(DHTPIN, DHTTYPE);

int R1 = 2; NexDSButton bt0 = NexDSButton(0, 8, "bt0"); NexText tTempC = NexText(0, 4, "tTempC"); NexText tHumidity = NexText(0, 6, "tHumidity"); uint32_t dual_state=0;

void setup(){ dht.begin();
nexInit(); pinMode(R1, OUTPUT); } void loop(){ bt0.getValue(&dual_state);

if(dual_state==1) //When pressed dual state button dual_state =1 { digitalWrite(R1, HIGH); } else if(dual_state==0) { digitalWrite(R1,LOW ); } float t = dht.readTemperature(); float h = dht.readHumidity();

if (isnan(h) || isnan(t)) { Serial2.println(F("Failed to read from DHT sensor!")); return; }

static char temperatureCTemp[10]; dtostrf(t, 6, 2, temperatureCTemp); tTempC.setText(temperatureCTemp);

char hTemp[10] = {0}; utoa(int(h), hTemp, 10); tHumidity.setText(hTemp);

Serial.print(F("Humidity: ")); Serial.print(h); Serial.print(F("% Temperature: ")); Serial.print(t); Serial.print("°C ");

}

This is my updated code to display the temperature and humidity in Nextion display and also to control the relay switching in Nextion display. It works good.

#include "NexDualStateButton.h"
#include "Nextion.h"
#include "DHT.h"

#define DHTPIN 27
#define DHTTYPE DHT22

DHT dht(DHTPIN, DHTTYPE);

int R1 = 2;
NexDSButton bt0 = NexDSButton(0, 8, "bt0");
NexText tTempC = NexText(0, 4, "tTempC");
NexText tHumidity = NexText(0, 6, "tHumidity");
uint32_t dual_state=0;

void setup(){
  dht.begin();  
  nexInit();
  pinMode(R1, OUTPUT);
}

void loop(){
  bt0.getValue(&dual_state);

  if(dual_state==1) //When pressed dual state button dual_state =1
  {
    digitalWrite(R1, HIGH);
  }
  else if(dual_state==0)
  {
    digitalWrite(R1,LOW ); 
  }
  float t = dht.readTemperature();
  float h = dht.readHumidity();
 
  if (isnan(h) || isnan(t)) {
    Serial2.println(F("Failed to read from DHT sensor!"));
    return;
  }

  static char temperatureCTemp[10];
  dtostrf(t, 6, 2, temperatureCTemp);
  tTempC.setText(temperatureCTemp);

  char hTemp[10] = {0}; 
  utoa(int(h), hTemp, 10);
  tHumidity.setText(hTemp);

  Serial.print(F("Humidity: "));
  Serial.print(h);
  Serial.print(F("%  Temperature: "));
  Serial.print(t);
  Serial.print("°C ");

}