Nextion Intelligent Display, Tracker SoM and CompButton

I could use a little help.

I have a project using a Particle Tracker and an HMI using a Nextion 7" Int. Display.

Most parts are working fine. I am using 0.0.18 of the included ITEADLIB libraries that were ported by ScruffR. I can send data to the display all day long and I have checked the continuity of the cables multiple times and RX <> TX. However, I cannot seem to get a button callback to work to save my life.

Some pertinent areas of code that might help:

From global section:

#include "Nextion.h"

USARTSerial& nexSerial = Serial1;

#include "Adafruit_ADS1X15.h"

Adafruit_ADS1115 ads;  /* Use this for the 16-bit version */

// Setup Nextion Objects

void test_callback(void *ptr);

NexText t_pre = NexText(1, 1, "pre");
NexText t_rc = NexText(1, 5, "run");
NexText nx_mode = NexText(1, 6, "gmMode");
NexText t_aJ = NexText(1, 16, "aJ");
NexText t_r0 = NexText(3,1,"r0");
NexText t_r1 = NexText(3,1,"r1");
NexText t_r2 = NexText(3,1,"r2");
NexText t_r3 = NexText(3,1,"r3");
NexText t_r4 = NexText(3,1,"r4");
NexText t_r5 = NexText(3,1,"r5");
NexText nx_date = NexText(1,25,"date");
NexText nx_time = NexText(1,26,"time");
NexText nx_run = NexText(1,26,"run");

NexButton nx_test = NexButton(1,27,"test");
//Setup Nextion Interupts for all possible touch events

NexTouch *nex_listen_list[] = 

The Callback function:

void test_callback(void *ptr){

   NexButton *btn = (NexButton *)ptr;

    nx_test.setText("Starting Test");


    Serial.println("<* FUNCTION TEST BUTTON PUSHED *>");


From Setup();



    nx_test.attachPop(test_callback, &nx_test);


Above, I have tried both nx_test.attachPOP and nx_test.attachPUSH. Neither has worked for me.

and I have the “nexLoop(nex_listen_list);” set up in loop();

I have tried to trigger a setText() function from the callback and I have resorted to just trying to get the program to Serial.Print(“TEST BUTTON”); whenever the button is pressed.

I have even tried to just Serial1.Read() and print whatever comes from the UART, but I get nothing. However, the display definitely updates when I send values from the program to the display via the objects.

Any help would be appreciated as always!

I do not have the editor in front of me but when you put the button on the screen did you check the box to send id (or something like that)?

1 Like

I am having someone else design the screens for me. This is a big project and we are dividing and conquering. I noticed this checkbox from another forum entry and I have enquired. I will hopefully get back to you with that answer sometime this weekend.


That has bit me several times when I have forgot to check that box.

Thanks, after talking with the screen designer over the weekend, this was exactly the problem.

Thanks for the quick response!