was not declared in this scope error

svncple

hi i am doing some qt examples i found online i am doing one for threading but keep getting the error was not declared in this scop

#ifndef DIALOG_H
#define DIALOG_H

#include <QDialog>
#include <QString>
#include "mythread.h"

namespace Ui {
class Dialog;
}

class Dialog : public QDialog
{
Q_OBJECT

public:
explicit Dialog(QWidget *parent = 0);
~Dialog();
MyThread *mythread;

private:
Ui::Dialog *ui;

public slots:
void onValueChanged(int);

private slots:
// for Start Button
void on_pushButton_clicked();

// for Stop Button
void on_pushButton_2_clicked();
};

#endif // DIALOG_H


#ifndef MYTHREAD_H
#define MYTHREAD_H

#include <QThread>

class MyThread : public QThread
{
Q_OBJECT
public:
explicit MyThread(QObject *parent = 0, bool b = false);
void run();

/*if Stop = true the thread will break
 *out of the loop, and will be disposed
 */
bool Stop;

signals:
//to communicat with gui thread we need to emit a signal
void valueChanged(int);

public slots:

} ;

#endif // MYTHREAD_H

next is the file with the error says mThread is not declared

#include "dialog.h"
#include "ui_dialog.h"

#include "mythread.h"

Dialog::Dialog(QWidget *parent) :
QDialog(parent),
ui(new Ui::Dialog)
{
ui->setupUi(this);

//create an instance of MyThread
mTheard = new MyThread;

// connect signal/slot
connect(mThread, SIGNAL(valueChanged(int)), this, SLOT(onValueChanged(int)));
}

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

/*Abosrb the signal emitted from a run() method
 *and reflect the count change to the count label
 *in our dialog
 */

void Dialog::onValueChanged(int count)
{
ui->label->setText(QString::number(count));
}

// Start Button
void Dialog::on_pushButton_clicked()
{
mThread->Stop = true;
}

//Stop Button
void Dialog::on_pushButton_2_clicked()
{
mThread->Stop = true;
} 


#include "mythread.h"
#include <QDebug>
MyThread::MyThread(QObject *parent) :
QThread(parent), Stop(b)
{

}

//run() will be called when a thread starts
void MyThread::run()
{
for(int i = 0; i <= 100; i++)
{
 QMutex mutex;
 //prevents other threads from changing "Stop" value
  mutex.lock();

    //emit the signal for the count label
    emit valueCahnged(i);

    // slowdown the count change, msec
    this->msleep(500);
}
}


#include <QApplication>
#include "dialog.h"

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
Dialog w;
w.show();

return a.exec();
}

mchinand

You have a typo:

//create an instance of MyThread
mTheard = new MyThread;

svncple

thanks for catching that dude, i fixed it but am still getting the error.

SGaist

Hi and welcome to devnet,

In your header you declared mythread not mThread

On a side note, your mutex won't work like you expect it to. First thing, you create a new mutex each time that function is called and second you never unlock it.