I am using QSingalMapper for multiple QSlider and QCheckBox both are working fine.I want to check signal sources in slot.But QObject::sender(); always returns NULL;
void MainWindow::UpdateTempValues(int val)
{
QSlider *m_slider = qobject_cast<QSlider*>(QObject::sender());
if(m_slider)
ui->label_34->setText(QString::number(m_slider->value()));
}
QSignalMapper *checkBoxMapper = new QSignalMapper(this);
QList <QSlider *> SliderList = this->findChildren <QSlider *>();
QList <QCheckBox *>CheckBoxList = this->findChildren<QCheckBox *>();
connect(signalMapper, SIGNAL(mapped(int)), this, SLOT(UpdateTempValues(int)));
connect(checkBoxMapper, SIGNAL(mapped(int)), this, SLOT(UpdateInOuConfigRegisters(int)));
foreach(QSlider *w, SliderList) {
signalMapper->setMapping(w,SignalMaperID);
connect(w, SIGNAL(valueChanged(int)), signalMapper, SLOT(map()));
SignalMaperID++;
}
SignalMaperID = 0;
foreach(QCheckBox *c,CheckBoxList){
checkBoxMapper->setMapping(c,SignalMaperID);
connect(c, SIGNAL(stateChanged(int)), checkBoxMapper, SLOT(map()));
SignalMaperID++;
}
Related
I knew that QSignalMapper work well for the condition like this:
QSignalMapper *signalMapper = new QSignalMapper(this);
connect(signalMapper, SIGNAL(mapped(int)), this, SIGNAL(SetSlice(int)));
connect(this->ui->button_1, SIGNAL(slicked()), signalMapper, SLOT(map()));
connect(this->ui->button_2, SIGNAL(clicked()), signalMapper, SLOT(map()));
connect(this->ui->button_3, SIGNAL(clicked()), signalMapper, SLOT(map()));
Now I want to implement 3 sliders all have one SLOT like buttons:
QSignalMapper *signalMapper = new QSignalMapper(this);
connect(signalMapper, SIGNAL(mapped(int)), this, SIGNAL(SetSlice(int)));
connect(this->ui->verticalSlider_1, SIGNAL(valueChanged(int)), signalMapper, SLOT(map()));
connect(this->ui->verticalSlider_2, SIGNAL(valueChanged(int)), signalMapper, SLOT(map()));
connect(this->ui->verticalSlider_3, SIGNAL(valueChanged(int)), signalMapper, SLOT(map()));
As you can see, this is contradictory with the consistent rule between SIGNAL and SLOT.
Is there a workaround here? I am using Qt4.
QSignalMapper is not about sending arguments from signals to slots but to let signal receiver know "who" was that or what data use. If you need to know both value and sender you either can use some internal class mapping, or use QObject * mapper and then cast QObject * to slider.
QSignalMapper * mapper = new QSignalMapper(this);
connect(mapper, SIGNAL(map(QWidget *)), this, SLOT(SetSlice(QWidget *)));
mapper->setMapping(this->ui->verticalSlider_1, this->ui->verticalSlider_1);
mapper->setMapping(this->ui->verticalSlider_2, this->ui->verticalSlider_2);
mapper->setMapping(this->ui->verticalSlider_3, this->ui->verticalSlider_3);
And here's slot body:
void YourClass::SetSlice(QWidget *wgt)
{
QSlider * slider = qobject_cast<QSlider *>(wgt);
if(slider) {
SetSlice(slider->value());
}
}
I want to pass selected QRadioButton's value from one Window to another. I am confused with the function declaration to accept the text value in Second Window, here is my code.
Window1.cpp
void SelectOS :: processNextButton(){
if(ui->win32->isChecked()){
QString loc = "WIN/32Bit";
SelectSoftware *ss = new SelectSoftware (loc);
this->hide();
ss->show();
}
else
{
//QMessageBox:warning();
}
}
Window2.h
public:
SelectSoftware(const QString &text, QWidget *parent=0);
Window2.cpp
SelectSoftware::SelectSoftware(const QString &text, QWidget *parent):QMainWindow(parent),ui(new ui::SelectSoftware)
{
QString softpath = text;
qDebug << softpath;
}
But when I call
ss = new SelectSoftware();
or
ss= new SelectSoftware(const QString &text, QWidget *parent);
in Window2.cpp, I get the error : no matching function for call to SelectSoftware::SelectSoftware()
Where am I wrong?
UPDATE
Window2.cpp
#include "selectsoftware.h"
#include "ui_selectsoftware.h"
SelectSoftware *ss;
QStringList selectedModuleList;
SelectSoftware::SelectSoftware(const QString &text, QWidget *parent) :
QMainWindow(parent),
ui(new Ui::SelectSoftware)
{
ui->setupUi(this);
softpath = text;
setWindowPosition();
getSoftwareDetails();
initializeUi();
}
SelectSoftware::~SelectSoftware()
{
delete ui;
}
void SelectSoftware::setWindowPosition()
{
QDesktopWidget *desktop = QApplication::desktop();
int x = (desktop->width() - size().width())/2;
int y = (desktop->height() - size().height())/2;
move(x, y-50);
setFixedSize(size().width(), size().height());
}
void SelectSoftware::cancel()
{
qApp->exit(0);
}
void SelectSoftware::showMainPage()
{
ss = new SelectSoftware(softpath); // here its creating problem, not going forward and app is crashing!!!
for(int j = 0; j < softwareList.size(); j++){
if(checkBox[j]->isChecked()){
if(!comboBox[j]->currentIndex()){
QMessageBox::warning(this, "Select version !", "Select version number for all selected software");
return;
}
}
}
for(int i = 0; i < softwareList.size(); i++){
if(checkBox[i]->isChecked()){
ss->selectedSoftList.push_back(checkBox[i]->text());
ss->selectedVerList.push_back(comboBox[i]->currentText());
}
}
if(!ss->selectedSoftList.size()){
QMessageBox::warning(this, "No product Selected !", "Select one");
return;
}
else{
SelectionPage* sp = new SelectionPage;
this->hide();
sp->show();
}
}
void SelectSoftware::test(const int id)
{
if(checkBox[id]->isChecked()){
comboBox[id]->setEnabled(true);
comboBox[id]->addItem(" Select anyone ");
QString path = qApp->applicationDirPath() + "/products/" + checkBox[id]->text();
QDir dir;
dir.cd(path);
dir.setFilter(QDir::Dirs | QDir::NoDotAndDotDot);
QFileInfoList list = dir.entryInfoList();
for (int i = 0; i < list.size(); ++i) {
QFileInfo fileInfo = list.at(i);
comboBox[id]->addItem(fileInfo.fileName());
}
}else{
comboBox[id]->clear();
comboBox[id]->setDisabled(true);
}
}
void SelectSoftware::getSoftwareDetails()
{
QString fileName = qApp->applicationDirPath() + "/abc/" + SOFTWARELIST;
QFile file(fileName);
if (!file.open(QIODevice::ReadOnly | QIODevice::Text)){
QString msg = "Could not find the file " + fileName;
errorExit(msg);
}
QTextStream in(&file);
while (!in.atEnd()) {
QString line = in.readLine();
processLine(line.toLower());
}
}
void SelectSoftware::processLine(QString str)
{
QStringList list = str.split(",");
QDir path = qApp->applicationDirPath() + "/products/" + list[0];
if(path.exists() && (list.size() == 2)){
QString tmp = list[0];
tmp = tmp.toLower();
softwareList.push_back(tmp);
}
}
void SelectOption::initializeUi()
{
this->setWindowTitle("Window2");
QGridLayout *gridLayout1 = new QGridLayout();
gridLayout1->setMargin(5);
gridLayout1->setSpacing(5);
QSignalMapper* signalMapper = new QSignalMapper();
for(int i = 0; i < list.size(); i++){
radioButton[i] = new QRadioButton();
radioButton[i]->setText(softwareList[i]);
signalMapper->setMapping(radioButton[i], i);
gridLayout1->addWidget(radioButton[i], i/1, i%1);
connect(radioButton[i], SIGNAL(clicked()),signalMapper, SLOT(map()));
}
connect(signalMapper, SIGNAL(mapped(const int &)),this, SIGNAL(radioChecked(const int &)));
connect(this, SIGNAL(radioChecked(const int &)),this, SLOT(test(const int)));
QGridLayout *gridLayout2 = new QGridLayout();
gridLayout2->setMargin(5);
gridLayout2->setSpacing(5);
for(int j = 0; j < list.size(); j++){
comboBox[j] = new QComboBox();
comboBox[j]->setDisabled(true);
gridLayout2->addWidget(comboBox[j], j/1, j%1);
}
QPushButton *nextButton = new QPushButton("Next >");
nextButton->setDefault(true);
connect(nextButton, SIGNAL(clicked()), this, SLOT(showMainPage()));
QPushButton *backButton = new QPushButton("< Back");
backButton->setDefault(true);
connect(backButton, SIGNAL(clicked()), this, SLOT(showSelectOS()));
QPushButton *cancelButton = new QPushButton("Cancel");
cancelButton->setDefault(true);
connect(cancelButton, SIGNAL(clicked()), this, SLOT(cancel()));
QHBoxLayout *hboxlayout;
hboxlayout = new QHBoxLayout();
hboxlayout->addLayout(gridLayout1);
hboxlayout->addLayout(gridLayout2);
QHBoxLayout *layout;
layout = new QHBoxLayout();
layout->addStretch(10);
layout->addWidget(nextButton);
layout->addWidget(backButton);
layout->addWidget(cancelButton);
layout->addStretch(10);
QVBoxLayout *mainLayout;
mainLayout = new QVBoxLayout();
mainLayout->addLayout(hboxlayout);
mainLayout->addLayout(layout);
ui->centralwidget->setLayout(mainLayout);
}
QVector<QString> SelectSoftware::getSelectedSoftware()
{
return ss->selectedSoftList;
}
QVector<QString> SelectSoftware::getSelectedVersion()
{
return ss->selectedVerList;
}
QStringList SelectSoftware::getSelectedModules()
{
return selectedModuleList;
}
First of all - use signals and slots, Luke
Second of all, you cannot call ss = new SelectSoftware();, since you haven't declared SelectSoftware constructor without parameters, and calling ss= new SelectSoftware(const QString &text, QWidget *parent); is illegal in C++.
SelectSoftware *ss = new SelectSoftware (loc); is correct, though.
1. In void SelectSoftware::processLine(QString str) addressing to list[0] without checking that list is not empty might be dangerous. I recomend you to add:
if (!list.size())
return;
right after initialization.
2. In void SelectOption::initializeUi() what is list? Are you sure list.size() <= softwareList.size()? If not, it's a potential problem.
3. What is radioButton? I don't see it's initialization. If it is QList < QRadioButton * >, than radioButton[i] = new QRadioButton(); is a bad one and you should do this:
radioButton.append(new QRadioButton());
4. Same goes to comboBox.
Each of the list can cause the crash of your application. And I could easily miss something.
For my GUI i would like to have two pairs of buttons that scroll up and down a scrollarea. The first set of buttons should work on say scrollarea1 and the second set of buttons should work on a scrollarea2. The widgets that I put in the scrollarea are called viewport1 and viewport2.
Since both both set of buttons should do the same (scrolling up and down) I thought I would make two slots called scrollUp and scrollDown that would handle the scrolling for both sets of buttons. Unfortunately I cannot make this work and need some help. I have tried the following:
QPushButton up;
QPushButton down;
QPushButton up2;
QPushButton down2;
connect(&up,SIGNAL(clicked()),&up,SLOT(scrollUp()));
connect(&up2,SIGNAL(clicked()),&up,SLOT(scrollUp()));
connect(&down,SIGNAL(clicked()),&down,SLOT(scrollDown()));
connect(&down2,SIGNAL(clicked()),&down,SLOT(scrollDown()));
void MainWindow::scrollDown()
{
QScrollArea area;
QWidget view;
if((QPushButton) &sender = down)
{
area=scrollArea;
view=viewport;
}
if((QPushButton) &sender = down2)
{
area=scrollArea;
view=viewport;
}
int curpos = area.verticalScrollBar()->value();
area.verticalScrollBar()->setValue(curpos+15);
int newpos = area.verticalScrollBar()->value();
QPoint topLeft = area.viewport()->rect().topLeft();
view.move(topLeft.x(),topLeft.y()-(newpos));
}
void MainWindow::scrollUp()
{
QScrollArea area;
QWidget view;
if((QPushButton) &sender = up)
{
area=scrollArea;
view=viewport;
}
if((QPushButton) &sender = up2)
{
area=scrollArea2;
view=viewport2;
}
int curpos = area.verticalScrollBar()->value();
area.verticalScrollBar()->setValue(curpos-15);
int newpos = area.verticalScrollBar()->value();
QPoint topLeft = area.viewport()->rect().topLeft();
view.move(topLeft.x(),topLeft.y()-(newpos));
}
But this doesn´t work for several reasons. I also tried giving the slot some arguments, something like:
connect(&up,SIGNAL(clicked()),&up,SLOT(scrollUp(scrollarea1,viewport1)));
connect(&up2,SIGNAL(clicked()),&up,SLOT(scrollUp(scrollarea2,viewport2)));
But again, no succes. Can anybody help me?
First of all, "It doesn't work" does not mean anything, and it is hard to help you if you do not say what errors you get. Then, there are few problems.
All QObject's derived classes are not copiable, it means you can not do
QWidget a;
QWidget b;
b = a; // Wrong
You should use pointers (or perhaps references).
QWidget a;
QWidget * b = new QWidget(...);
QWidget * c;
c = & a; // Ok
c = b; // Ok
Then your connect calls are wrong:
connect(&up, SIGNAL(clicked()), &up, SLOT(scrollUp()));
The third argument is the object who has the slot. up is a QPushButton, it does not have a scrollUp() slot, it is your MainWindow who does:
connect(&up, SIGNAL(clicked()), this, SLOT(scrollUp()));
(since connect is called in MainWindow's constructor this points to the current MainWindow object).
Also in C++ the single = sign means assignment, for equality comparison use =='. Andsender` is a function.
Your approach should work if implemented in the right way:
class MainWindow: public QWidget
{
QScrollArea * scroll1;
QScrollArea * scroll2;
QWidget * view1;
QWidget * view2;
QPushButton * up1;
QPushButton * up2;
QPushButton * down1;
QPushButton * down2;
public:
MainWindow()
{
// Here initialize member variables.
...
connect(up1, SIGNAL(clicked()), this, SLOT(scrollUp()));
connect(up2, SIGNAL(clicked()), this, SLOT(scrollUp()));
connect(down1, SIGNAL(clicked()), this, SLOT(scrollDown()));
connect(down2, SIGNAL(clicked()), this, SLOT(scrollDown()));
}
public slots:
void scrollDown()
{
QScrollArea * area;
QWidget * view;
if(qobject_cast<QPushButton>(sender()) == down1) {
area = & scroll1;
view = & view1;
} else if(qobject_cast<QPushButton>(sender()) == down2) {
area = & scroll2;
view = & view2;
} else {
// Error.
}
// Now `area` and `view` point to the right widgets.
...
}
void scrollUp()
{
// The same as before.
}
};
Another approach would be to extract the actual scrolling instructions to a separate function:
class MainWindow: public QWidget
{
// Same variables as before
...
public:
MainWindow()
{
// Here initialize member variables.
...
connect(up1, SIGNAL(clicked()), this, SLOT(scrollUp1()));
connect(up2, SIGNAL(clicked()), this, SLOT(scrollUp2()));
connect(down1, SIGNAL(clicked()), this, SLOT(scrollDown1()));
connect(down2, SIGNAL(clicked()), this, SLOT(scrollDown2()));
}
public slots:
void scrollDown(QScrollArea * area, QWidget * view)
{
// Here you scroll over `area` and `view`.
}
void scrollDown1()
{
scrollDown(scroll1, area1);
}
void scrollDown2()
{
scrollDown(scroll2, area2);
}
// Again, the same for `scrollUp`.
};
There are several mistakes in your code :
About the sender of the signal : There is not a QObject called "sender" but a method QObject * QObject::sender() const; which returns a pointer on the sender of the signal.
In the if conditions : you are casting a QPushButton** into a QPushButton ((QPushButton) &sender) and you dont compare that thing with your buttons up(2) and down(2).
In your connections between slots and signals : the scrollUp and scrollDown slots do not belong to the QPushButton class but to your MainWindow class.
Finally, you should write something like this :
connect(&up, SIGNAL(clicked()), this, SLOT(scrollUp()));
connect(&up2, SIGNAL(clicked()), this, SLOT(scrollUp()));
connect(&down, SIGNAL(clicked()), this, SLOT(scrollDown()));
connect(&down2, SIGNAL(clicked()), this, SLOT(scrollDown()));
void MainVindow::scrollDown() {
// [...]
QPushButton * senderButton = qobject_cast<QPushButton *>(this->sender());
// QPushButton * senderButton = (QPushButton *) this->sender(); works too
if (senderButton == &down) {
// [...]
}
if (senderButton == &down2) {
// [...]
}
// [...]
}
void MainVindow::scrollUp() {
// [...]
QPushButton * senderButton = qobject_cast<QPushButton *>(this->sender());
// QPushButton * senderButton = (QPushButton *) this->sender(); works too
if (senderButton == &up) {
// [...]
}
if (senderButton == &up2) {
// [...]
}
// [...]
}
First of all the slot can have no other arguments than the signal hands to it. Clicked has no arguments and there fore the slot can have no arguments.
I would think that the easiest way to check whether scrollArea 1 or 2 has focus and decide from that which one should move.
I also think that there is an error in your code. Shouldn't this:
if((QPushButton) &sender = down2)
{
area=scrollArea;
view=viewport;
}
Be this:
if((QPushButton) &sender = down2)
{
area=scrollArea2;
view=viewport2;
}
First of all, this is pseudo code. It won't compile, but it should contain the necessary information.
I believe this problem can be most elegantly solved using the QSignalMapper class. It allows parameterless signals from multiple senders to connect to one slot.
In the header, write something like this:
class QSignalMapper;
class MainWindow : public QMainWindow
{
public:
void init();
public slots:
void handleScrollButtons(int id);
private:
enum { ScrollUp1, ScrollDown1, ScrollUp2, ScrollDown2 } // just makes it more convenient to use
QSignalMapper *m_scrollbuttonhandler;
}
In the source file, write something like this
#include <QSignalMapper>
void MainWindow::init()
{
m_scrollbuttonhandler = new QSignalMapper(this);
m_scrollbuttonhandler->setMapping(scrollup1button, ScrollUp1);
m_scrollbuttonhandler->setMapping(scrolldown1button, ScrollDown1);
m_scrollbuttonhandler->setMapping(scrollup2button, ScrollUp2);
m_scrollbuttonhandler->setMapping(scrolldown2button, ScrollDown2);
connect(scrollup1button, SIGNAL(clicked(bool)), m_scrollbuttonhandler, SLOT(map()));
connect(scrolldown1button, SIGNAL(clicked(bool)), m_scrollbuttonhandler, SLOT(map()));
connect(scrollup2button, SIGNAL(clicked(bool)), m_scrollbuttonhandler, SLOT(map()));
connect(scrolldown2button, SIGNAL(clicked(bool)), m_scrollbuttonhandler, SLOT(map()));
connect(m_scrollbuttonhandler, SIGNAL(mapped(int)), this, SLOT(handleScrollButtons(int)));
}
void MainWindow::handleScrollButtons(int id)
{
switch (id)
{
case ScrollUp1:
// stuff to do for scrollup1button
case ScrollDown1:
// stuff to do for scrolldown1button
case ScrollUp2:
// stuff to do for scrollup2button
case ScrollDown2:
// stuff to do for scrolldown2button
}
}
Hello all
I have class that inherited from Qtreeview and I implement simple ( empty ) mousePressEvent function
But whenever I try to do this , the selection of the items in the Qtreeview are disabled , when I remove this function everything is working fine
What im missing here ?
Here Is the code:
void MyTreeWidget::mousePressEvent(QMouseEvent *event)
{
QModelIndex index = this->indexAt(event->pos());
QAbstractItemModel *model = this->model();
QMap<int, QVariant> ItemData = model->itemData(index);
QMap<int, QVariant>::const_iterator i = ItemData.constBegin();
while (i != ItemData.constEnd()) {
QString k = QString::number(i.key());
QString v = i.value().toString();
++i;
}
if (event->button() == Qt::LeftButton) {
QByteArray itemData ;
QString urlTo;
itemData.append(urlTo);
QDrag *drag = new QDrag(this);
QMimeData *mimeData = new QMimeData;
mimeData->setData("application/x-dnditemdata", itemData);
drag->setMimeData(mimeData);
Qt::DropAction dropAction = drag->exec(Qt::MoveAction);
if (dropAction == Qt::MoveAction)
{
UT::getInstance()->LogToFile("dropAction");
}
}
QTreeView::mousePressEvent(event);
}
It's because that when you override a method, the original on is not called anymore. You would have to manually call the mousePressEvent method of QTreeView in the method you created.
Here is how to do it:
void YourClass::mousePressEvent ( QMouseEvent * event )
{
QTreeView::mousePressEvent(event);
}
Hope this helps.
Is there something similar to the (PyQT)
QTreeWidgetItem.setCheckState(0, Qt.Checked) but for the combo box?
I can't see anything in the reference, so how can I insert a custom QComboBox as one of the elements within QTreeWidgetItem?
Use QTreeWidget::setItemWidget ( QTreeWidgetItem * item, int column, QWidget * widget ) to put the combo box into the cells.
For example, let's make all rows of the second column of a 2-column QTreeWidget to all be combo boxes:
QTreeWidgetItemIterator it(ui->treeWidget);
while (*it) {
QComboBox *comboBox = new QComboBox(this);
comboBox->addItems(QStringList() << "item1" << "item2");
ui->treeWidget->setItemWidget(*it, 1, comboBox);
++it;
}
Our example widget now looks like this:
I know this is an old question but I think I have a more thorough answer. To get any functionality out of the QComboBox, you'll probably need to subclass it. Here's the solution that I came up with:
#ifndef COMBOBOXITEM_H
#define COMBOBOXITEM_H
#include
class ComboBoxItem : public QComboBox
{
Q_OBJECT
private:
QTreeWidgetItem *item;
int column;
public:
ComboBoxItem(QTreeWidgetItem*, int);
public slots:
void changeItem(int);
};
ComboBoxItem::ComboBoxItem(QTreeWidgetItem *item, int column)
{
this->item = item;
this->column = column;
connect(this, SIGNAL(currentIndexChanged(int)), SLOT(changeItem(int)));
}
void ComboBoxItem::changeItem(int index)
{
if(index >=0)
{
item->setData(this->column, Qt::UserRole, this->itemText(index));
qDebug() item->data(this->column, Qt::UserRole).toString();
}
}
#include "moc_ComboBoxItem.cpp"
#endif // COMBOBOXITEM_H
////// Sample implementation..
lst = new QTreeWidget;
// Snip
QTreeWidgetItem *itm = new QTreeWidgetItem;
// Snip
ComboBoxItem *cmb = new ComboBoxItem(itm, 1);
cmb->addItem("One");
cmb->addItem("Two");
cmb->addItem("Three");
cmb->addItem("Four");
lst->setItemWidget(itm, 1, cmb);
I hope that helps someone in need of a QComboBox inside of a QTreeWidgetItem!
Use
setItemWidget(QTreeWidgetItem( ), column, QWidget( ) )
.Just add your QComboBox() as a parameter, as it inherits QWidget() so it is compatible.
tree = QTreeWidget()
cmb = QComboBox()
cmb.addItem("Item1", 'value1')
cmb.addItem("Item2", 'value2')
cmb.addItem("Item3", 'value3')
item = QTreeWidgetItem(tree.invisibleRootItem())
column = 0
item.setData(column, Qt.EditRole, 'NameYouWant')
column += 1
tree.setItemWidget(item, column , cmb)
Here is small fix to the another posters method. I found that is uses Data to update the box How ever I made small change to setText updater for the method.
#ifndef COMBOBOXITEM_H
#define COMBOBOXITEM_H
#include <QtGui>
class ComboBoxItem : public QComboBox
{
Q_OBJECT
private:
QTreeWidgetItem *item;
int column;
public:
ComboBoxItem(QTreeWidgetItem*, int);
public slots:
void changeItem(int);
};
ComboBoxItem::ComboBoxItem(QTreeWidgetItem *item, int column)
{
this->item = item;
this->column = column;
connect(this, SIGNAL(currentIndexChanged(int)), SLOT(changeItem(int)));
}
void ComboBoxItem::changeItem(int index)
{
if(index >=0)
{
this->item->setText(this->column, this->currentText());
}
}
#include "moc_ComboBoxItem.cpp"
#endif // COMBOBOXITEM_H
////// Sample implementation..
lst = new QTreeWidget;
// Snip
QTreeWidgetItem *itm = new QTreeWidgetItem;
// Snip
ComboBoxItem *cmb = new ComboBoxItem(itm, 1);
cmb->addItem("One");
cmb->addItem("Two");
cmb->addItem("Three");
cmb->addItem("Four");
lst->setItemWidget(itm, 1, cmb);
This is easiest method:
QComboBox *cb = new QComboBox(this);
QStringList cbTexts;
cbTexts << tr("First") << tr("Second") << tr("Third");
cb->addItems(cbTexts);
QTreeWidgetItem *item = new QTreeWidgetItem(ui->treeWidget);
ui->treeWidget->addTopLevelItem(item);
ui->treeWidget->setItemWidget(item, [colum here], cb);
for (int col = 0; col < [num colums]; ++col) ui->treeWidget->resizeColumnToContents(col);