I have added checkboxes in QtreeWidget ,How can i add functions to that checkboxes ?

Hello

I have added checkboxes in QtreeQidget , I can check or uncheck them . But How can i add functions to that checkboxes ?
for example if i click one check box then a certain function is performed.

I have attached Image file
Your suugestions would be highly appreciated ...
thanks
Attachment 11236

By connecting signals to slots. Read the docs.

I have seen Signals and slots but could not figure it out how to use them in this case.

Here is txt file which i want to open and load it in qtreewidget

1200,Shahbaz,Ifc,laja
2001,ali,Step,kdh
1992,ikaka,psp,ayaj


Here is my code

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

ui->label_OrigName->setText("File Name :");
ui->label_FilePath->setText("File Path :");

//set the number of columns

ui->treeWidget->setColumnCount(5);
addRoot ("ID","Type","Name","UID","Check");

//set the headers
// ui->treeWidget->setHeaderLabels(QStringList()<<"ID"<<"Type"<<"Nam e"<<"GUID");

}

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

void QT_ApplicationWindow::on_pushButton_Openfile_click ed()
{
QString fileName = QFileDialog::getOpenFileName(
this, tr ("Open File"), "C:\\",
"All files (*.*);; Text File (*.txt);; IFC File (*.ifc);; STEP File (*.step);;XML files (*.xml);;Image files (*.jpg *.png)");
if (!fileName.isEmpty())
ui->label_FileName->setText(QFileInfo(fileName).fileName());
QDir dir = QFileInfo(fileName).absoluteDir();
ui->lineEdit_FileDir->setText(dir.absolutePath());

QFile file(fileName);

if (!file.open(QIODevice::ReadOnly | QIODevice ::Text))
QMessageBox::critical(this,tr("STOP"),tr("Error with loading"));

QTextStream in(&file);
QString line;
// ui->textBrowser->setText(in.readAll());
do
{
line = in.readLine();
if(line.isEmpty())
continue;
QTreeWidgetItem *item = new QTreeWidgetItem (ui->treeWidget);
item->setFlags(item->flags() | Qt::ItemIsUserCheckable | Qt::ItemIsSelectable | Qt::ItemIsEditable);

QList <QString> parts = line.split(",", QString::KeepEmptyParts);
QString L;
QListIterator<QString> Iter (parts);

while (Iter.hasNext())
{
for (int i=0 ; i<4; i++)
{
L = Iter.next();
item->setText(i,L);
item->setCheckState(4,Qt::Unchecked);
}
}
} while (!in.atEnd());

}



void QT_ApplicationWindow :: addRoot(QString ID, QString Type, QString Name, QString UID, QString A)
{

}

When do you want to perform these actions;

1. immediately after the check state changes on each item, or
2. for all checked items when an "OK" button is clicked?

1. Connect to the dataChanged() signal from the tree widget's model()
2. In your button slot, iterate over the column of the tree checking the check state and acting on those that are checked/unchecked.

I want to know
when i check the particular checkbox , message box appears .....