Add a minus sign to a number with Nextion

Other Hardware Displays
1

Hello,
I am using a Nextion 7" Intelligent display, and Seithan's EasyNextion Library to control it. I have a very simple program to control a stepper motor. If a switch component is on, I want to turn the number of steps negative to get the stepper to go counter-clockwise, but just can't get it to work. I think it's probably syntax, but I've tried every permutation I can think of, and still no go. It just runs the code as if there were no minus sign. Any ideas?

#include <EasyNextionLibrary.h>
#include <trigger.h>
#include <Stepper.h>

EasyNex myNex(Serial);

int in1Pin = 8;
int in2Pin = 9;
int in3Pin = 10;
int in4Pin = 11;

Stepper motor(2048, in1Pin, in2Pin, in3Pin, in4Pin);

int numStp1 = 1;
int numStp2 = 0;
int numStp3 = 1;
uint32_t numSpd1 = 1;
uint32_t swClk;

void setup() {
   myNex.begin(9600);// put your setup code here, to run once:
   pinMode(in1Pin, OUTPUT);
   pinMode(in2Pin, OUTPUT);
   pinMode(in3Pin, OUTPUT);
   pinMode(in4Pin, OUTPUT);
}

void loop() {
   myNex.NextionListen();// put your main code here, to run repeatedly:   
}

void trigger0() {
  numStp1 = myNex.readNumber("sStp.val");
  myNex.writeNum("nStp.val", numStp1 + numStp2);
}

void trigger1() {
  numStp2 = myNex.readNumber("sStpG.val");
  myNex.writeNum("nStp.val", numStp1 + numStp2);
}

void trigger2(){
  numSpd1 = myNex.readNumber("sSpd.val");
  myNex.writeNum("sSet.val", numSpd1);
}

void trigger5(){
  swClk = myNex.readNumber("swCl.val");
  if(swClk == 1)
  {
    numStp3 = myNex.readNumber("nStp.val");
    (numStp3 * -1);
  }
    else(swClk == 0);
    {
    numStp3 = myNex.readNumber("nStp.val");
    }
  motor.setSpeed(numSpd1);
  motor.step(numStp3);
  digitalWrite(in1Pin, LOW);
  digitalWrite(in2Pin, LOW);
  digitalWrite(in3Pin, LOW);
  digitalWrite(in4Pin, LOW);
}
2

This doesn't do anything:

    (numStp3 * -1);

Try:

    numStp3 =(numStp3 * -1);
3

That helped, but I also had to move the line

  numStp3 = myNex.readNumber("nStp.val");

out of the if:else.
Thanks!

4

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