QMouseEvent

.h

void mousePressEvent(QMouseEvent *event);

.cpp

bool pressed; //global

void MainWindow::mousePressEvent(QMouseEvent *event)
{
if (event->button()==Qt::RightButton)
{
    qDebug() << "right button is pressed";
    pressed=true;
}
}

Check Comport

quint16 serial_usb_vendor_id;
quint16 serial_usb_product_id;
QString vendor = "D:/vendor.txt";
bool chk_status_comport=true;

ui->setup

timer_A = new QTimer(this);

connect(timer_A,SIGNAL(timeout()),this,SLOT(check_usb_comport()));
timer_A->start(100);


serial = new QSerialPort(this);
connect(serial,SIGNAL(readyRead()),this,SLOT(readData()));
ui->bt_connect->click();

void MainWindow::check_usb_comport()

{

//    if(serial->isOpen())

//    {

//        serial->close();

//        ui->bt_connect->setText("Connect");

//    }

//    else

//    {

//        serial->setPortName("COM21");

//        serial->setBaudRate(QSerialPort::Baud115200);

//        serial->setDataBits(QSerialPort::Data8);

//        serial->setFlowControl(QSerialPort::NoFlowControl);

//        serial->setParity(QSerialPort::EvenParity);

//        serial->setStopBits(QSerialPort::OneStop);

//        if( serial->open(QIODevice::ReadWrite))

//        {

//            ui->bt_connect->setText("Disconnect");

//        }

//        else

//        {

//            // QMessageBox::critical(this,tr("Error"),serial->errorString());

//            QMessageBox::information(this,"Wrong com port" ,"Please check comport");

//        }

//    }

    if ( chk_status_comport == true)

    {

      bool serial_is_available = false;

      ui->btn_read_vendor_file->click();

      QString serial_uno_port_name;

      foreach (const QSerialPortInfo &serialPortInfo, QSerialPortInfo::availablePorts())

      {

        if (serialPortInfo.hasProductIdentifier() && serialPortInfo.hasVendorIdentifier()) {

          if ((serialPortInfo.productIdentifier() == serial_usb_product_id)

              && (serialPortInfo.vendorIdentifier() == serial_usb_vendor_id)) {

            serial_is_available = true; //    serial uno is available on this port

            serial_uno_port_name = serialPortInfo.portName();

          }

        }

      }

      if (serial_is_available)

      {

        //qDebug() << "++++++++++++++++++++++++++++++++++";

        serial->setPortName(serial_uno_port_name);

        serial->open(QSerialPort::ReadWrite);

        serial->setBaudRate(QSerialPort::Baud115200);

        serial->setDataBits(QSerialPort::Data8);

        serial->setFlowControl(QSerialPort::NoFlowControl);

        serial->setParity(QSerialPort::NoParity);

        serial->setStopBits(QSerialPort::OneStop);

        serial->setParity(QSerialPort::EvenParity);

         ui->label_status_comport->setText("Comport Connected");

      }

      else {

          qDebug() << "------------------------------------------";

        ui->label_status_comport->show();

        ui->label_status_comport->setText("Unable to Commicate with PLC");

        //QMessageBox::information(this, "Serial Port Error", "Unable to Commicate with MCU.");

        chk_status_comport = false;

      }

    }

    else {

      ui->btn_read_vendor_file->click();

      QString serial_uno_port_name;

      foreach (const QSerialPortInfo &serialPortInfo, QSerialPortInfo::availablePorts())

      {

        //  check if the serialport has both a product identifier and a vendor identifier

        if (serialPortInfo.hasProductIdentifier() && serialPortInfo.hasVendorIdentifier()) {

          if ((serialPortInfo.productIdentifier() == serial_usb_product_id)

              && (serialPortInfo.vendorIdentifier() == serial_usb_vendor_id)) {   //  serial_is_available = true;

            serial_uno_port_name = serialPortInfo.portName();

          }

        }

      }

      if (serial->isOpen())

      {

        serial->close();

      }

      else

      {

        serial->setPortName(serial_uno_port_name);

        serial->setBaudRate(QSerialPort::Baud115200);

        serial->setDataBits(QSerialPort::Data8);

        serial->setStopBits(QSerialPort::OneStop);

        serial->setFlowControl(QSerialPort::NoFlowControl);

        serial->setParity(QSerialPort::EvenParity);

        if ( serial->open(QIODevice::ReadWrite))

        {

          //qDebug() << "==========================";

          chk_status_comport = true;

          ui->label_status_comport->show();

          ui->label_status_comport->setText("Comport Connected");

        }

        else

        {

          ui->label_status_comport->show();

          ui->label_status_comport->setText("Unable to Commicate with PLC");

          //QMessageBox::information(this, "Serial Port Error", "Unable to Commicate with MCU.");

        }

      }

    }

}

Qt Serial

.pro
#-------------------------------------------------
#
# Project created by QtCreator 2015-12-10T22:35:58
#
#-------------------------------------------------

QT       += core gui serialport

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = SerialPlayqt
TEMPLATE = app


SOURCES += main.cpp\
        mainwindow.cpp

HEADERS  += mainwindow.h

FORMS    += mainwindow.ui








*****************************************************************


.h


#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QtSerialPort/QSerialPort>
#include <QDebug>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private slots:
    void on_bt_connect_clicked();
    void readData();


    void on_bt_connect_2_clicked();

private:
    Ui::MainWindow *ui;
    QSerialPort *serial;

};

#endif // MAINWINDOW_H





*****************************************************************


 ui->setupUi(this);


//---- COMPORT ------------------------------------------------
                foreach (const QSerialPortInfo &info, QSerialPortInfo::availablePorts()) {
                QStringList list;
                list << info.portName();
                ui->portnamebox->addItem(list.first(),list);
                }





*****************************************************************

void MainWindow::on_bt_connect_clicked()
{
    if(serial->isOpen())
    {
        serial->close();
        ui->bt_connect->setText("Connect");
    }

    else
    {
    serial->setPortName(ui->portnamebox->currentText()); 
    serial->setBaudRate(QSerialPort::Baud115200);
    serial->setDataBits(QSerialPort::Data8);
    serial->setFlowControl(QSerialPort::NoFlowControl);
    serial->setParity(QSerialPort::EvenParity);
    serial->setStopBits(QSerialPort::OneStop);

        if( serial->open(QIODevice::ReadWrite))
        {
            ui->bt_connect->setText("Disconnect");
        }

        else
        {
           // QMessageBox::critical(this,tr("Error"),serial->errorString());
            QMessageBox::information(this,"Wrong com port" ,"Please check comport");
        }
    }
}







void MainWindow::readData()
{
        responseData.append(serial->readAll());
        ui->logstext->append(responseData.toHex().toUpper());

        ReadTruck01(responseData);
        qDebug() << "recive = " << responseData.append(serial->readAll()) ;

}





void MainWindow::on_bt_connect_2_clicked()
{
    qDebug() << "click <----";
    QByteArray data;

    data[0] = 0x01;
    data[1] = 0x03;
    data[2] = 0x00;
    data[3] = 0x00;
    data[4] = 0x00;
    data[5] = 0x5F;

    serial->write(data);

}

Qt float

setStyleSheet

ui->label_tmt->setStyleSheet("background-color: rgb(0, 0, 0);");

QTimer signalSlot

//-------------------- .h -----------------------------

#ifndef MAINWINDOW_H

#define MAINWINDOW_H
#include <QMainWindow>
#include <QTimer>
#include <QDebug>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
   Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

   private slots:
    void updates();

private:
    Ui::MainWindow *ui;
    QTimer *timer;

};

#endif // MAINWINDOW_H

//------------------------ .cpp ----------------

#include "mainwindow.h"

#include "ui_mainwindow.h"

int cnt =0;

MainWindow::MainWindow(QWidget *parent) :

    QMainWindow(parent),

    ui(new Ui::MainWindow)

{

    ui->setupUi(this);

    QTimer *timer = new QTimer(this);

       connect(timer, SIGNAL(timeout()), this, SLOT(updates()));

       timer->start(300);

}

MainWindow::~MainWindow()

{

    delete ui;

}

void MainWindow::updates(){

cnt++;

qDebug() << "Timer = " << cnt;

}

QFile and Cutter String ( , )

#include <QString>
#include <QStringRef>
#include <QFile>
#include <QStringList>
#include <QRegExp>

QString vendor = "/home/pi/hino/hino/vendor.txt";


void MainWindow::on_btn_write_vendor_file_clicked()

{

       QFile vendorFile(vendor);

       if(!vendorFile.open(QFile::WriteOnly | QFile::Text))

       {

          qDebug() << "could not open file vendor for write";

           return;

       }

       QTextStream data(&vendorFile);

         QString data1 =  ui->lineEdit_vendor_file->text();

         QString data2 =   "," ;

         QString data3 =   ui->lineEdit_product_file->text();

         QString datas = +"," +data1+data2+data3;

       data << datas;

       vendorFile.flush();

       vendorFile.close();

}

void MainWindow::on_btn_read_vendor_file_clicked()

{

    QFile vendorFile(vendor);

    if(!vendorFile.open(QFile::ReadOnly | QFile::Text))

    {

        qDebug() << "could not open file vendor for Read";

        return;

    }

    QTextStream data(&vendorFile);

    QString datas = data.readAll(); // 1234 , 5678

    QRegExp tagExp(",");

    QStringList firstList = datas.split(tagExp);

    QString requiredPart1 = firstList.value(firstList.length()-2);

    QString requiredPart2 = firstList.value(firstList.length()-1);

     qDebug() <<  "  requiredPart1 = " << requiredPart1;

     qDebug() <<  "  requiredPart2 = " << requiredPart2;

     bool ok1,ok2;

     serial_uno_vendor_id  = requiredPart1.toInt(&ok1,10);

     serial_uno_product_id = requiredPart2.toInt(&ok2,10);

 ui->lineEdit_vendor_file->setText( requiredPart1);

 ui->lineEdit_product_file->setText(requiredPart2);

    vendorFile.flush();

    vendorFile.close();

}

 void rl_write_file::WriteFile(QString data)
{
    qDebug() << "WriteFile";

    QFile gpsLog(pathFile);
    //if(!gpsLog.open(QFile::WriteOnly | QFile::Text))
    if (!gpsLog.open(QIODevice::WriteOnly | QIODevice::Append))
    {
        qDebug() << "could not open file vendor for write";
        return;
    }
    QTextStream save(&gpsLog);

    save << data;
    qDebug() << data;
    gpsLog.flush();
    gpsLog.close();


}

Dialog

==============================

void checkconcurrent::on_btn_export_clicked()
{
    QString textData;
    int rows = model->rowCount();
    int columns = model->columnCount();

    for (int i = 0; i < rows; i++)
    {
        for (int j = 0; j < columns; j++)
        {

                textData += model->data(model->index(i,j)).toString();
                textData += ", " ;     // for .csv file format
        }
        textData += "\n";             // (optional: for new line segmentation)
    }

    // [Save to file] (header file <QFile> needed)
    // .csv
     QString fileName = QFileDialog::getSaveFileName(this, tr("Save Address Book"), "",  tr("Address Book (*.csv);;All Files (*)"));
 
     QFile csvFile(fileName);
    if(csvFile.open(QIODevice::WriteOnly | QIODevice::Truncate)) {

        QTextStream out(&csvFile);
        out << textData; 
        csvFile.close();
    } 
}