Separate QT Widget Instances

Question

I think my problem is very simple and I'm probably overlooking something incredibly obvious, but I haven't been able to solve this for a little while now.

In my current QT project, I have a 2 files, one of them is a window, another is a widget. My window calls upon my "custom" widget and creates an instance of it and injects it into the frame. This placing of the widget into the window is controlled by a button which can be clicked many times because I ultimately want many instances of the widget on the screen at once.

Here's the problem: Whenever a new instance of my widget is placed in the frame, they seem to just be mirroring each others values, meaning when I do stuff within the first instance of the widget, it happens in every instance of the widget (however, it sometimes doesn't appear to update right away, but I know that it happens). I want them to be separate instances which will in the future interact with each other.

Here's how I'm handling injecting the widget:

    void Window::on_btnNewCell_clicked()
    {
        ui->verLay->addWidget(new Neuron());
    }

And here's the main portion of my widget's code:

#include "neuron.h"
#include "ui_neuron.h"
#include "qtimer.h"

// Define Neuron Properties
int volt = -70;
int rest = -70;
int max = 40;

// Logic Contol
int excAmt = 10;
int inhAmt = -10;
bool refract = false;
bool timerActive;
bool st = true;

Neuron::Neuron(QWidget *parent):QWidget(parent), ui(new Ui::Neuron)
{
    ui->setupUi(this);
    //Homeostatic Voltage Changing Timer
    tiHom = new QTimer(this);
    connect(tiHom, SIGNAL(timeout()), this, SLOT(changeVoltage()),Qt::DirectConnection );

    //Duration of mouse depression timer
    tiPrs = new QTimer(this);
    connect(tiPrs, SIGNAL(timeout()), this, SLOT(chgVltg()),Qt::DirectConnection );
    timerActive = false;
}

Neuron::~Neuron()
{
    delete ui;
}

// CUSTOM METHODS
void Neuron::changeVoltage(int c)
{
    volt = (volt + c);

    if (volt >= max) // begin action potential
    {
        volt = rest;
        timerActive = false;
        tiHom->stop();
        ui->chkFired->setChecked(true);
    }

    if (volt <= rest) // to not drop below -40
    {
        if (timerActive == true)
        {
            timerActive = false;
            tiHom->stop();
        }
        volt = rest;
    }

    else if (volt >= rest) // to drop it to -40
    {
        if (timerActive == false)
        {
            timerActive = true;
            tiHom->start(100);
        }
    }
    ui->lblVolt->setText(QString::number(volt));
}

void Neuron::changeVoltage()
{
    changeVoltage(-1);
}

void Neuron::chgVltg()
{
    if (st == true)
    {
        changeVoltage(excAmt);
    }
    else
        changeVoltage(inhAmt);
}
void Neuron::updateGlow(int i, bool b)
{
    QPixmap pic;
    if (b == true) {
        if (st == true) pic.load(":/Images/Excitatory/" +QString::number(i) +".png");
        else pic.load(":/Images/Inhibitory/" +QString::number(i) +".png");
        ui->lblE->setPixmap(pic);
        ui->lblE->setEnabled(true);
        tiPrs->start(100);
    }
    else
    {
        ui->lblE->setEnabled(false);
        tiPrs->stop();
    }
}
//many additional redundant methods for a lack of an efficient way of implementing them

Answer 1

'volt' isn't a member variable - it's a file local variable. There's only one of them. Make it a member variable (put it in the class), and your problem will vanish.

Something like:

class Neuron {
private:
  int volt;
};

And in the constructor, set it's initial value:

Neuron::Neuron(QWidget *parent) : QWidget(parent), ui(new Ui::Neuron), volt(5) 
{ /* existing code */ }