Getting changed values of a QTablewidget into a QStringList

Kushan

In my qt c++ application I want to get the changed values of a Qtablewidget into a qt stringList! I used the on_tableWidget_cellChanged() method for this! But I get all the values of the table widget into the qstringList

following is my code
MainWIndow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

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

private slots:
    void on_pushButton_clicked();

    void on_tableWidget_cellChanged(int row, int column);


private:
    QStringList changedValues;
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

MainWindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    ui->tableWidget->setColumnCount(1);
    ui->tableWidget->setRowCount(5);
    for(int i=0;i<5;i++){
        ui->tableWidget->setItem(i,0,new QTableWidgetItem(QString::number(i)));
    }
}

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



void MainWindow::on_tableWidget_cellChanged(int row, int column)
{
changedValues<<ui->tableWidget->item(row,column)->text();

}

void MainWindow::on_pushButton_clicked()
{
    QString concat;
    for(int i=0;i<changedValues.size();i++){
        concat+=changedValues[i];
    }
    ui->label->setText(concat);

}

though I changed 0(value of 0th row, 0th column) to 8 and clicked the button it displayed 012348! I want to display only 8 (the new value) how can i achieve this?

Charlie_Hdz

@Kushan said in getting changed values of a QTablewidget into a stringList:

In my qt c++ application I want to get the changed values of a Qtablewidget into a qt stringList! I used the on_tableWidget_cellChanged() method for this! But I get all the values of the table widget into the qstringList

Which is the signal that is connected to the on_tableWidget_cellChanged() slot?

Kushan

@Charlie_Hdz It automatically when you ight click the tablewidget and select slots there no need a signal

VRonin

Unfortunately I think this is a limitation of uic.
ui->setupUi(this); will do the connection to on_tableWidget_cellChanged and then it gets called when you do ui->tableWidget->setItem(i,0,new QTableWidgetItem(QString::number(i)));
Just rename on_tableWidget_cellChanged to onCellChanged and call QObject::connect(ui->tableWidget,&QTableWidget::cellChanged,this,&MainWindow::onCellChanged); at the end of the constructor

P.S.
ui->tableWidget->setItem(i,0,new QTableWidgetItem(QString::number(i))); this is just bad

QTableWidgetItem* const newItem= new QTableWidgetItem;
newItem->setData(Qt::EditRole,i);
ui->tableWidget->setItem(i,0,newItem);

Kushan

@VRonin I dont understand what you are saying can u edit in my code and show? its a great help

VRonin

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

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

private slots:
    void on_pushButton_clicked();

    void onCellChanged(int row, int column);


private:
    QStringList changedValues;
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    ui->tableWidget->setColumnCount(1);
    ui->tableWidget->setRowCount(5);
    for(int i=0;i<5;i++){
       QTableWidgetItem* const newItem= new QTableWidgetItem;
newItem->setData(Qt::EditRole,i);
ui->tableWidget->setItem(i,0,newItem);
    }
QObject::connect(ui->tableWidget,&QTableWidget::cellChanged,this,&MainWindow::onCellChanged);
}

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



void MainWindow::onCellChanged(int row, int column)
{
changedValues<<ui->tableWidget->item(row,column)->text();

}

void MainWindow::on_pushButton_clicked()
{
    QString concat;
    for(int i=0;i<changedValues.size();i++){
        concat+=changedValues[i];
    }
    ui->label->setText(concat);

}

Kushan

@VRonin now I get 0000011111222223333344444488888 :O

VRonin

This is strange. could you try if this snippet works for you?

#include <QApplication>
#include <QWidget>
#include <QVBoxLayout>
#include <QPushButton>
#include <QTableWidget>
#include <QLabel>
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QWidget mainWid;
    QStringList changedValues;
    QVBoxLayout* mainLay=new QVBoxLayout(&mainWid);
    QTableWidget* tableWidget = new QTableWidget(&mainWid);
    QPushButton* button = new QPushButton(QStringLiteral("Display list"),&mainWid);
    QLabel* resultLabel = new QLabel(&mainWid);
    mainLay->addWidget(tableWidget);
    mainLay->addWidget(button );
    mainLay->addWidget(resultLabel );
    tableWidget->setColumnCount(1);
    tableWidget->setRowCount(5);
    for(int i=0;i<5;i++){
        QTableWidgetItem* const newItem= new QTableWidgetItem;
        newItem->setData(Qt::EditRole,i);
        tableWidget->setItem(i,0,newItem);
    }
    QObject::connect(tableWidget,&QTableWidget::cellChanged,[&changedValues,tableWidget](int row, int column)->void{changedValues<<tableWidget->item(row,column)->text();});
    QObject::connect(button ,&QPushButton::clicked,[&changedValues,resultLabel ]()->void{resultLabel->setText(changedValues.join(','));});
    mainWid.show();
    return a.exec();

}