Adding A QComboBox to the header of QtreeView having multiple columns and a custom model

prady_80

Is it possible to add a QComboBox in the header item of the Qtreeview class backed up by a custom model. I have headerData overriden in the model and against the Qt:DisplayRole label text are returned back as QVariant. I am also able to add an Icon on the header using Qt:DecorationRole. How do I add a ComboBox??
Please help

SGaist

Hi and welcome to DevNet,

A quick google search turned "this":http://blog.qt.digia.com/blog/2012/09/28/qt-support-weekly-27-widgets-on-a-header/ up.

Hope it helps

prady_80

Thanks a lot SGaist...
That really helped.
For others that are trying to do the same, I am posting the sample code.

@#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QComboBox>
#include <QGridLayout>
#include <QCheckBox>
#include <QTableView>
#include <QStyledItemDelegate>
#include <QHeaderView>

#include <QtGui>
#include <QLabel>
#include <QDebug>

class MainWindow : public QMainWindow
{
Q_OBJECT

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

class HeaderObject : public QWidget{
Q_OBJECT
public:
HeaderObject(QWidget *parent = 0) : QWidget(parent){
QComboBox *c = new QComboBox(this);
// QCheckBox cb = new QCheckBox(this);
QLabel objLabel = new QLabel();
objLabel->setText("Testy");
c->addItem("test");
c->addItem("test2");
QHBoxLayout *h = new QHBoxLayout;
//l->addWidget(c);
// l->addWidget(cb);
h->addWidget(objLabel);
h->addWidget(c);
setLayout(h);
}
};

class CustomModel : public QAbstractTableModel{
Q_OBJECT
public:
CustomModel() : QAbstractTableModel(){
}

int rowCount(const QModelIndex &parent = QModelIndex()) const{return 5;}
int columnCount(const QModelIndex &parent = QModelIndex()) const {return 5;}
QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const{
    if (role == Qt::DisplayRole) return QVariant();
    return QVariant();
}

QVariant headerData(int section,
                                         Qt::Orientation orientation, int role) const
{
    qDebug() << "CSapActvtyTreeModel::headerData" << endl;
    if (orientation == Qt::Horizontal && role == Qt::DisplayRole) {
        return QVariant();
    }
    return QAbstractTableModel::headerData(section,orientation,role);
}

private:
};

class CustomHeader : public QHeaderView{
Q_OBJECT
public Q_SLOTS:
void handleSectionResized(int i)
{
qDebug() << "HandleSectionResized :" << i;
for (int j = i; j<5;j++) {
int logical = j;
headerSections[logical]->setGeometry(sectionViewportPosition(logical), 0,
sectionSize(logical) - 5, height());
}
}

void handleSectionMoved(int logical, int oldVisualIndex, int newVisualIndex)
{
    int ilogicalIndex = logical;
    for (int i=qMin(oldVisualIndex, newVisualIndex);i<count();i++){
        ilogicalIndex = logicalIndex(i);
        headerSections[ilogicalIndex]->setGeometry(sectionViewportPosition(ilogicalIndex), 0,
                                       sectionSize(ilogicalIndex) - 5, height());
    }
}

public:
CustomHeader(QWidget *parent = 0):QHeaderView(Qt::Horizontal, parent){

    for(int i = 0; i<5; i++){
        headerSections.insert(i,new HeaderObject(this));
        headerSections[i]->hide();
    }

    setMinimumSectionSize(headerSections[0]->minimumSizeHint().width());
    setDefaultSectionSize(headerSections[0]->minimumSizeHint().width());
    setSectionsMovable(true);
    connect(this, SIGNAL(sectionResized(int,int,int)), this,
                SLOT(handleSectionResized(int)));

}

protected:
void paintSection(QPainter *painter, const QRect &rect, int logicalIndex) const {
if (!rect.isValid())
return;
//qDebug() << logicalIndex;
//qDebug() << "QRect: " << rect << " AND OFFSET:" << offset();
// headerSections[logicalIndex]->setGeometry(rect);
// headerSections[logicalIndex]->show();
QHeaderView::paintSection(painter,rect,logicalIndex);
}

void showEvent(QShowEvent *e)
{
    for (int i=0;i<5;i++) {
       headerSections[i]->setGeometry(sectionViewportPosition(i), 0,
                                                 sectionSize(i) - 5, height());
       headerSections[i]->show();
    }
    QHeaderView::showEvent(e);
 }

QSize sizeHint() const {
    QSize s = size();
    s.setHeight(headerSections[0]->minimumSizeHint().height());
    return s;
}

private:
mutable QVector< QPointer <HeaderObject> > headerSections;
};

/// The call
int main(int argc, char *argv[])
{
QApplication a(argc, argv);

CustomModel *model = new CustomModel;
QTableView *view = new QTableView();
view->setModel(model);

view->setHorizontalHeader(new CustomHeader(view));
view->show();
return a.exec&#40;&#41;;

}

@

Please note here that you will need to update the header positions in the overriden method
void scrollContentsBy(int dx, int dy) so that when you scroll the headers also scroll

NeoQt

hi prady_80
i m trying similar solution i m new to Qt could you please post full owrking soltion where event can be handle for each of combox .and apply filter model..

NeoQt

hi prady_80
i m trying similar solution i m new to Qt could you please post full owrking soltion where event can be handle for each of combox .and apply filter model..

prady_80

Hi,
I have put a Git for you.
Pull the sample from there. I suggest you build a complex realistic model, modify with filter proxy to handle complexity and then learn. That way you will have a better understanding of Qt Model-View architecture.
Hope it helps.
"Git link":https://github.com/PSaraph/Qt-Header-view-combo.git
Happy learning

prady_80

Hi,
I have put a Git for you.
Pull the sample from there. I suggest you build a complex realistic model, modify with filter proxy to handle complexity and then learn. That way you will have a better understanding of Qt Model-View architecture.
Hope it helps.
"Git link":https://github.com/PSaraph/Qt-Header-view-combo.git
Happy learning