Add widget right aligned to a QTableWidget cell

[VRonin]

@hbatalha said in Add widget right aligned to a QTableWidget cell:

I getting this error when trying to create a signal in the delegate:

Can you show your code?

what's so wrong with setIndexWidget, creating a delegate seems so complex so I am asking what are the advantages of it over setIndexWidget?

Try creating 1000 rows and scroll through them. You'll realise very quick what the problem is. setIndexWidget is a HOG on resources

[hbatalha]

@VRonin Sorry for the really late reply, I have been working offline due to internet cut.

@VRonin said in Add widget right aligned to a QTableWidget cell:

Try creating 1000 rows and scroll through them. You'll realise very quick what the problem is. setIndexWidget is a HOG on resources

I Will try that, I am curious to see it

Can you show your code?

#ifndef TAILBUTTONSDELEGATE_H
#define TAILBUTTONSDELEGATE_H

#include <QApplication>
#include <QTableView>
#include <QStandardItemModel>
#include <QStyledItemDelegate>
#include <QHeaderView>
#include <QPushButton>

class TailButtonsDelegate : public QStyledItemDelegate
{
    Q_OBJECT
    Q_DISABLE_COPY(TailButtonsDelegate)

public:
    explicit TailButtonsDelegate(QObject* parent = Q_NULLPTR)
        :QStyledItemDelegate(parent)
    {}
    void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        Q_ASSERT(index.isValid());
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        const QWidget *widget = option.widget;
        QStyle *style = widget ? widget->style() : QApplication::style();
        style->drawControl(QStyle::CE_ItemViewItem, &opt, painter, widget);


        QStyleOptionButton editButtonOption;
        editButtonOption.text = QString(); //use emoji for text, optionally you can use icon + iconSize
        editButtonOption.rect = QRect(option.rect.left()+option.rect.width()-(2*option.rect.height()),option.rect.top(),option.rect.height(),option.rect.height());
        editButtonOption.features = QStyleOptionButton::None;
        editButtonOption.direction = option.direction;
        editButtonOption.fontMetrics = option.fontMetrics;
        editButtonOption.palette = option.palette;
        editButtonOption.styleObject = option.styleObject;
        QStyleOptionButton removeButtonOption(editButtonOption);
        removeButtonOption.text = QString(); //use emoji for text, optionally you can use icon + iconSize
        removeButtonOption.rect = QRect(option.rect.left()+option.rect.width()-option.rect.height(),option.rect.top(),option.rect.height(),option.rect.height());
        style->drawControl(QStyle::CE_PushButton, &editButtonOption, painter, widget);
        style->drawControl(QStyle::CE_PushButton, &removeButtonOption, painter, widget);
    }
    QSize sizeHint(const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        const QSize baseSize = QStyledItemDelegate::sizeHint(option,index);
        return QSize(baseSize.width()+(2*baseSize.height()),baseSize.height());
    }
    QWidget* createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QWidget* result = new QWidget(parent);
        result->setGeometry(option.rect);
        QWidget* baseEditor = QStyledItemDelegate::createEditor(result,option,index);
        baseEditor->setObjectName("baseEditor");
        baseEditor->setGeometry(0,0,option.rect.width()-(2*option.rect.height()),option.rect.height());
        QPushButton* editButton = new QPushButton(result);
        editButton->setObjectName("editButton");
        editButton->setGeometry(option.rect.width()-(2*option.rect.height()), 0, option.rect.height(),option.rect.height());
        connect(editButton,&QPushButton::clicked,[]()
        {
            qDebug("Edit");
        });
        QPushButton* removeButton = new QPushButton(result);
        removeButton->setObjectName("removeButton");
        removeButton->setGeometry(option.rect.width()-option.rect.height(), 0, option.rect.height(),option.rect.height());
        connect(editButton,&QPushButton::clicked,this,std::bind(&TailButtonsDelegate::clicked,this,index));
        return result;
    }
    void setEditorData(QWidget *editor, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        QStyledItemDelegate::setEditorData(baseEditor,index);
    }
    void setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        QStyledItemDelegate::setModelData(baseEditor,model,index);
    }
    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        Q_UNUSED(index)
        editor->setGeometry(option.rect);
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        baseEditor->setGeometry(0,0,option.rect.width()-(2*option.rect.height()),option.rect.height());
        QWidget* editButton = editor->findChild<QWidget*>("editButton");
        Q_ASSERT(editButton);
        editButton->setGeometry(option.rect.width()-(2*option.rect.height()), 0, option.rect.height(),option.rect.height());
        QWidget* removeButton = editor->findChild<QWidget*>("removeButton");
        Q_ASSERT(removeButton);
        removeButton->setGeometry(option.rect.width()-option.rect.height(), 0, option.rect.height(),option.rect.height());
        editor->setGeometry(option.rect);
    }

    Q_SIGNAL void clicked(const QModelIndex &index);
};

#endif // TAILBUTTONSDELEGATE_H

Also I want to set the button size to setFixedSize(10, 10); but I have been having problems controlling the size. For the time being I have being using this version using setIndexWidget

    QWidget* widget = new QWidget;

    QPushButton* detailsButton = new QPushButton;
    detailsButton->setFixedSize(10, 10);

    QHBoxLayout* hLayout = new QHBoxLayout;
    hLayout->addStretch();
    hLayout->addWidget(detailsButton);
    widget->setLayout(hLayout);

    ui->tableWidget->setIndexWidget(ui->tableWidget->model()->index(row, 0), widget);

So above is what I am trying to achieve using delegate.

[hbatalha]

Also the button is still not clickable

[VRonin]

Sorry for the delay in getting back to you, I've been offline for a few days. Try this:

#ifndef TAILBUTTONDELEGATE_H
#define TAILBUTTONDELEGATE_H

#include <QApplication>
#include <QStyledItemDelegate>
#include <QPushButton>
#include <QMouseEvent>
class TailButtonDelegate : public QStyledItemDelegate
{
    Q_OBJECT
#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0)
    Q_DISABLE_COPY_MOVE(TailButtonDelegate)
#else
    Q_DISABLE_COPY(TailButtonDelegate)
#endif
public:
    explicit TailButtonDelegate(QObject* parent = Q_NULLPTR)
        :QStyledItemDelegate(parent)
    {}
    void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        Q_ASSERT(index.isValid());
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        const QWidget *widget = option.widget;
        QStyle *style = widget ? widget->style() : QApplication::style();
        style->drawControl(QStyle::CE_ItemViewItem, &opt, painter, widget);
        QStyleOptionButton buttonOption = buttonOptions(opt);
        style->drawControl(QStyle::CE_PushButton, &buttonOption, painter, widget);
    }
    QSize sizeHint(const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        const QSize baseSize = QStyledItemDelegate::sizeHint(option,index);
        const QRect butRect = buttonRect(opt);
        return QSize(baseSize.width()+butRect.width(),qMax(butRect.height(),baseSize.height()));
    }
    QWidget* createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QWidget* result = new QWidget(parent);
        result->setGeometry(option.rect);
        QWidget* baseEditor = QStyledItemDelegate::createEditor(result,option,index);
        result->setFocusProxy(baseEditor);
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        const QRect butRect = buttonRect(opt);
        baseEditor->setObjectName("baseEditor");
        baseEditor->setGeometry(0,0,opt.rect.width()-butRect.width(),opt.rect.height());
        QPushButton* extraButton = new QPushButton(result);
        extraButton->setObjectName("extraButton");
        extraButton->setText(m_buttonText);
        extraButton->setIcon(m_buttonIcon);
        extraButton->setGeometry(opt.rect.width()-butRect.width(), 0, butRect.width(),butRect.height());
        connect(extraButton,&QPushButton::clicked,this,&TailButtonDelegate::clickedHelper);
        return result;
    }
    void setEditorData(QWidget *editor, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        currentIndex = index;
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        QStyledItemDelegate::setEditorData(baseEditor,index);
    }
    void setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        QStyledItemDelegate::setModelData(baseEditor,model,index);
    }
    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        editor->setGeometry(opt.rect);
        const QRect butRect = buttonRect(opt);
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        baseEditor->setGeometry(0,0,opt.rect.width()-butRect.width(),opt.rect.height());
        QWidget* extraButton = editor->findChild<QWidget*>("extraButton");
        Q_ASSERT(extraButton);
        extraButton->setGeometry(opt.rect.width()-butRect.width(), 0, butRect.width(),butRect.height());
    }
    const QString buttonText() const
    {
        return m_buttonText;
    }
    void setButtonText(const QString &newButtonText)
    {
        m_buttonText = newButtonText;
    }
    const QIcon &buttonIcon() const
    {
        return m_buttonIcon;
    }
    void setButtonIcon(const QIcon &newButtonIcon)
    {
        m_buttonIcon = newButtonIcon;
    }
Q_SIGNALS:
    void buttonClicked(const QModelIndex &index);
protected:
    bool editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &option, const QModelIndex &index) Q_DECL_OVERRIDE{
        Q_ASSERT(event);
        Q_ASSERT(model);
        Qt::ItemFlags flags = model->flags(index);
        if ((option.state & QStyle::State_Enabled) && (flags & Qt::ItemIsEnabled)){
            if (event->type() == QEvent::MouseButtonRelease) {
                QStyleOptionViewItem viewOpt(option);
                initStyleOption(&viewOpt, index);
                const QRect butRect = buttonRect(viewOpt);
                QMouseEvent *me = static_cast<QMouseEvent*>(event);
                if (me->button() == Qt::LeftButton && butRect.contains(me->pos())){
                    currentIndex = index;
                    clickedHelper();
                }
            }
        }
        return QStyledItemDelegate::editorEvent(event,model,option,index);
    }
    virtual QStyleOptionButton buttonOptions(const QStyleOptionViewItem &option, bool skipRct=false) const{
        const QWidget *widget = option.widget;
        QStyle *style = widget ? widget->style() : QApplication::style();
        int buttonIconSize = style->pixelMetric(QStyle::PM_ButtonIconSize, 0, widget);
        QStyleOptionButton buttonOption;
        buttonOption.text = m_buttonText;
        buttonOption.icon = m_buttonIcon;
        buttonOption.iconSize = (QSize(buttonIconSize,buttonIconSize));
        buttonOption.rect = skipRct ? QRect() : buttonRect(option);
        buttonOption.features = QStyleOptionButton::None;
        buttonOption.direction = option.direction;
        buttonOption.fontMetrics = option.fontMetrics;
        buttonOption.palette = option.palette;
        buttonOption.styleObject = option.styleObject;
        buttonOption.state = option.state;
        return buttonOption;
    }
    virtual QRect buttonRect(const QStyleOptionViewItem &option) const{
        const QStyleOptionButton buttonOption = buttonOptions(option,true);
        const QWidget *widget = option.widget;
        QStyle *style = widget ? widget->style() : QApplication::style();
        QSize buttonSize = style->sizeFromContents(QStyle::CT_PushButton, &buttonOption, QSize(), widget);
        buttonSize.setWidth(qMin(buttonSize.width(),option.rect.width()/2));
        return QRect(option.rect.left()+option.rect.width()-buttonSize.width(),option.rect.top(),buttonSize.width(),qMax(buttonSize.height(),option.rect.height()));
    }
private:
    mutable QModelIndex currentIndex;
    QString m_buttonText;
    QIcon m_buttonIcon;
    void clickedHelper(){buttonClicked(currentIndex);}
};

#endif // TAILBUTTONDELEGATE_H

Then you can use it with something like:

int main(int argc, char *argv[])
{
    QApplication app(argc,argv);
    QTableWidget wid(2,2);
    TailButtonDelegate *butDelegate = new TailButtonDelegate(&wid);
    butDelegate->setButtonText("Test");
    QPixmap bluePixmap(20,20);
    bluePixmap.fill(Qt::blue);
    QIcon blueIcon;
    blueIcon.addPixmap(bluePixmap);
    butDelegate->setButtonIcon(blueIcon);
    QObject::connect(butDelegate,&TailButtonDelegate::buttonClicked,[](const QModelIndex& index){qDebug() << "Clicked " << index;});
    wid.setItemDelegate(butDelegate);
    wid.show();
    return app.exec();

}

[VRonin]

@hbatalha said in Add widget right aligned to a QTableWidget cell:

Also I want to set the button size to setFixedSize(10, 10);

To do this in the example above you'd need to tweak the buttonRect() method to something like

virtual QRect buttonRect(const QStyleOptionViewItem &option) const{
    return QRect(option.rect.left()+option.rect.width()-10,option.rect.top(),10,10);
}

[hbatalha]

@VRonin It's working greatly, thanks, but I want to access some QPushButton methods, namely setCheckable, isChecked, setChecked, setToolTip. Also I want to emit signal when the mouse enters the button, I tried doind that but it's not working.
This is what I have tried to get a signal when mouse enters the button

#ifndef TAILBUTTONSDELEGATE_H
#define TAILBUTTONSDELEGATE_H

#include <QApplication>
#include <QStyledItemDelegate>
#include <QPushButton>
#include <QMouseEvent>

class MyButton : public QPushButton
{
    Q_OBJECT

public:
    MyButton(QWidget* parent = 0) : QPushButton(parent) {}
    ~MyButton() {};

signals:
    void mouseIn();

protected:
    void enterEvent(QEnterEvent*) override
    {
        emit mouseIn();
    }
};

class TailButtonDelegate : public QStyledItemDelegate
{
    Q_OBJECT
#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0)
    Q_DISABLE_COPY_MOVE(TailButtonDelegate)
#else
    Q_DISABLE_COPY(TailButtonDelegate)
#endif
public:
    explicit TailButtonDelegate(QObject* parent = Q_NULLPTR)
        :QStyledItemDelegate(parent)
    {}
    void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        Q_ASSERT(index.isValid());
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        const QWidget *widget = option.widget;
        QStyle *style = widget ? widget->style() : QApplication::style();
        style->drawControl(QStyle::CE_ItemViewItem, &opt, painter, widget);
        QStyleOptionButton buttonOption = buttonOptions(opt);
        style->drawControl(QStyle::CE_PushButton, &buttonOption, painter, widget);
    }
    QSize sizeHint(const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        const QSize baseSize = QStyledItemDelegate::sizeHint(option,index);
        const QRect butRect = buttonRect(opt);
        return QSize(baseSize.width()+butRect.width(),qMax(butRect.height(),baseSize.height()));
    }
    QWidget* createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QWidget* result = new QWidget(parent);
        result->setGeometry(option.rect);
        QWidget* baseEditor = QStyledItemDelegate::createEditor(result,option,index);
        result->setFocusProxy(baseEditor);
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        const QRect butRect = buttonRect(opt);
        baseEditor->setObjectName("baseEditor");
        baseEditor->setGeometry(0,0,opt.rect.width()-butRect.width(),opt.rect.height());
        MyButton* myButton = new MyButton(result);
        myButton->setObjectName("myButton");
        myButton->setText(m_buttonText);
        myButton->setIcon(m_buttonIcon);
        myButton->setGeometry(opt.rect.width()-butRect.width(), 0, butRect.width(),butRect.height());
        connect(myButton, &MyButton::clicked, this, &TailButtonDelegate::clickedHelper);
        connect(myButton, &MyButton::mouseIn, this, &TailButtonDelegate::mouseInHelper);
        return result;
    }
    void setEditorData(QWidget *editor, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        currentIndex = index;
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        QStyledItemDelegate::setEditorData(baseEditor,index);
    }
    void setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        QStyledItemDelegate::setModelData(baseEditor,model,index);
    }
    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE
    {
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        editor->setGeometry(opt.rect);
        const QRect butRect = buttonRect(opt);
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        baseEditor->setGeometry(0,0,opt.rect.width()-butRect.width(),opt.rect.height());
        QWidget* myButton = editor->findChild<QWidget*>("myButton");
        Q_ASSERT(myButton);
        myButton->setGeometry(opt.rect.width()-butRect.width(), 0, butRect.width(),butRect.height());
    }
    const QString buttonText() const
    {
        return m_buttonText;
    }
    void setButtonText(const QString &newButtonText)
    {
        m_buttonText = newButtonText;
    }
    const QIcon &buttonIcon() const
    {
        return m_buttonIcon;
    }
    void setButtonIcon(const QIcon &newButtonIcon)
    {
        m_buttonIcon = newButtonIcon;
    }
Q_SIGNALS:
    void clicked(const QModelIndex &index);
    void mouseIn(const QModelIndex &index);
protected:
    bool editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &option, const QModelIndex &index) Q_DECL_OVERRIDE
    {
        Q_ASSERT(event);
        Q_ASSERT(model);
        Qt::ItemFlags flags = model->flags(index);
        if ((option.state & QStyle::State_Enabled) && (flags & Qt::ItemIsEnabled))
        {
            if (event->type() == QEvent::MouseButtonRelease)
            {
                QStyleOptionViewItem viewOpt(option);
                initStyleOption(&viewOpt, index);
                const QRect butRect = buttonRect(viewOpt);
                QMouseEvent *me = static_cast<QMouseEvent*>(event);
                if (me->button() == Qt::LeftButton && butRect.contains(me->pos()))
                {
                    currentIndex = index;
                    clickedHelper();
                }
            }
            if (event->type() == QEvent::Enter)
            {
                {
                    currentIndex = index;
                    mouseInHelper();
                }
            }
        }
        return QStyledItemDelegate::editorEvent(event,model,option,index);
    }
    virtual QStyleOptionButton buttonOptions(const QStyleOptionViewItem &option, bool skipRct=false) const
    {
        const QWidget *widget = option.widget;
        QStyle *style = widget ? widget->style() : QApplication::style();
        int buttonIconSize = style->pixelMetric(QStyle::PM_ButtonIconSize, 0, widget);
        QStyleOptionButton buttonOption;
        buttonOption.text = m_buttonText;
        buttonOption.icon = m_buttonIcon;
        buttonOption.iconSize = (QSize(buttonIconSize,buttonIconSize));
        buttonOption.rect = skipRct ? QRect() : buttonRect(option);
        buttonOption.features = QStyleOptionButton::None;
        buttonOption.direction = option.direction;
        buttonOption.fontMetrics = option.fontMetrics;
        buttonOption.palette = option.palette;
        buttonOption.styleObject = option.styleObject;
        buttonOption.state = option.state;
        return buttonOption;
    }
    virtual QRect buttonRect(const QStyleOptionViewItem &option) const
    {
        const QStyleOptionButton buttonOption = buttonOptions(option,true);
        const QWidget *widget = option.widget;
        QStyle *style = widget ? widget->style() : QApplication::style();
        QSize buttonSize = style->sizeFromContents(QStyle::CT_PushButton, &buttonOption, QSize(), widget);
        buttonSize.setWidth(qMin(buttonSize.width(),option.rect.width()/2));
        return QRect(option.rect.left()+option.rect.width()-10,option.rect.top(),10,10);
    }
private:
    mutable QModelIndex currentIndex;
    QString m_buttonText;
    QIcon m_buttonIcon;
    void clickedHelper()
    {
        clicked(currentIndex);
    }
    void mouseInHelper()
    {
        mouseIn(currentIndex);
    }
};

#endif // TAILBUTTONSDELEGATE_H

but it is not working.

[hbatalha]

Also I would like have the button in the middle of the cell(top - bottom), this when set the size to (10,10)

[hbatalha]

Update: I was able to solve all the problems mentioned above except for the mouse over event signal.
So now I just want a way to signal when the mouse goes over the delegate, I have tried many "solutions" none has worked yet for me.

[VRonin]

Sorry for the choppy response. Your delegate code is doing the right thing (just minor note it should handle QEvent::HoverEnter instead of QEvent::Enter), the problem is that hover events are not passed by the view to the delegate. You need to subclass your view and reimplement viewportEvent to something like: (warning: untested code)

class HoverDelegateView : public QTableView{
    Q_OBJECT
#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0)
    Q_DISABLE_COPY_MOVE(HoverDelegateView)
#else
    Q_DISABLE_COPY(HoverDelegateView)
#endif
public:
    explicit HoverDelegateView(QWidget *parent = Q_NULLPTR)
        : QTableView(parent)
    {}
protected:
    bool viewportEvent(QEvent *event) Q_DECL_OVERRIDE
    {
        switch (event->type()){
        case QEvent::HoverMove:
        case QEvent::HoverEnter:
        case QEvent::HoverLeave:{
#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
            QModelIndex index = indexAt(static_cast<QHoverEvent*>(event)->position().toPoint());
            QStyleOptionViewItem options;
            initViewItemOption(&options);
#else
            QModelIndex index = indexAt(static_cast<QHoverEvent*>(event)->pos());
            QStyleOptionViewItem options = viewOptions();
#endif
            QModelIndex buddy = model()->buddy(index);
            options.rect = visualRect(buddy);
            options.state |= (buddy == currentIndex() ? QStyle::State_HasFocus : QStyle::State_None);
            QAbstractItemDelegate *delegate = itemDelegate(index);
            delegate->editorEvent(event, model(), options, buddy);
            break;
        }
        default:
            break;
        }
        return QAbstractItemView::viewportEvent(event);
    }
};

[hbatalha]

@VRonin I understood what you said, the concept behind it. In the code there are two undeclared identifiers: viewOptions and index though.

[VRonin]

@hbatalha said in Add widget right aligned to a QTableWidget cell:

@VRonin I understood what you said, the concept behind it. In the code there are two undeclared identifiers: viewOptions and index though.

Thanks, fixed those

[VRonin]

@hbatalha said in Add widget right aligned to a QTableWidget cell:

Also I would like have the button in the middle of the cell(top - bottom), this when set the size to (10,10)

Again this is managed by buttonRect, the 3rd argument to be precise:

virtual QRect buttonRect(const QStyleOptionViewItem &option) const{
    return QRect(option.rect.left()+option.rect.width()-10,option.rect.top()+qMax(0,(option.rect.height()-10)/2),10,10);
}

[hbatalha]

@VRonin I will test the code and get back to you.

[hbatalha]

@VRonin I figured that out.

[hbatalha]

@VRonin I thought you edited the reply to fix the undeclared identifiers errors in the code but they are still there.

[JonB]

@hbatalha
You wrote earlier

In the code there are two undeclared identifiers: viewOptions and index though.

Looking at those in @VRonin's code now they should be fine? If you have a compilation error show it.

[hbatalha]

This post is deleted!

[hbatalha]

@JonB

When I include it and tried to use it theses errors we thrown.

[VRonin]

@hbatalha I edited my post above to take care of these issues

[hbatalha]

@VRonin yeah it is compiling now but it's not emitting the HoverEnter signal unfortunately:
buttondelegate.h

#ifndef BUTTONDELEGATE_H
#define BUTTONDELEGATE_H

#include <QApplication>
#include <QStyledItemDelegate>
#include <QPushButton>
#include <QMouseEvent>
#include <QToolTip>
#include <QPainter>
#include <QPalette>
#include <QTableWidget>

class MyButton : public QPushButton
{
    Q_OBJECT

public:
    MyButton(QWidget* parent = 0) : QPushButton(parent) {}
    ~MyButton() {};

signals:
    void mouseIn();

protected:
    void enterEvent(QEnterEvent*) override
    {
        emit mouseIn();
    }
};

class ButtonDelegate : public QStyledItemDelegate
{
    Q_OBJECT
#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0)
    Q_DISABLE_COPY_MOVE(ButtonDelegate)
#else
    Q_DISABLE_COPY(ButtonDelegate)
#endif
public:
    explicit ButtonDelegate(QObject* parent)
        :QStyledItemDelegate(parent),
         tableWidget(qobject_cast<QTableWidget*>(parent))
    {
        mIsChecked = false;
        isDetailsButton = false;
        isEnabled = true;
        isHidden = false;
    }
    void update()
    {
        tableWidget->viewport()->update();
    }
    void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const override
    {
        Q_ASSERT(index.isValid());

        bool shouldPaint = false;
        if(isDetailsButton)
        {
            if(index.column() == 0)
                shouldPaint = true;
        }
        else
            shouldPaint = true;

        if(shouldPaint)
        {
            QStyleOptionViewItem opt = option;
            initStyleOption(&opt, index);
            const QWidget *widget = option.widget;

            QStyle *style = widget ? widget->style() : QApplication::style();
            style->drawControl(QStyle::CE_ItemViewItem, &opt, painter, widget);
            QStyleOptionButton buttonOption = buttonOptions(opt);

            if(! isHidden)
            {
                style->drawControl(QStyle::CE_PushButton, &buttonOption, painter, widget);
            }
        }
        else
            QStyledItemDelegate::paint(painter, option, index);
    }
    QSize sizeHint(const QStyleOptionViewItem &option, const QModelIndex &index) const override
    {
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        const QSize baseSize = QStyledItemDelegate::sizeHint(option,index);
        const QRect butRect = buttonRect(opt);
        return QSize(baseSize.width()+butRect.width(),qMax(butRect.height(),baseSize.height()));
    }
    QWidget* createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const override
    {
        QWidget* result = new QWidget(parent);
        result->setGeometry(option.rect);
        QWidget* baseEditor = QStyledItemDelegate::createEditor(result,option,index);
        result->setFocusProxy(baseEditor);
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        const QRect butRect = buttonRect(opt);
        baseEditor->setObjectName("baseEditor");
        baseEditor->setGeometry(0,0,opt.rect.width()-butRect.width(),opt.rect.height());
        MyButton* myButton = new MyButton(result);
        myButton->setObjectName("myButton");
        myButton->setText(m_buttonText);
        myButton->setIcon(m_buttonIcon);
        myButton->setEnabled(false);
        myButton->setGeometry(opt.rect.width()-butRect.width(), 0, butRect.width(),butRect.height());
        connect(myButton, &MyButton::clicked, this, &ButtonDelegate::clickedHelper);
        connect(myButton, &MyButton::mouseIn, this, &ButtonDelegate::mouseInHelper);
        return result;
    }
    void setEditorData(QWidget *editor, const QModelIndex &index) const override
    {
        currentIndex = index;
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        QStyledItemDelegate::setEditorData(baseEditor,index);
    }
    void setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const override
    {
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        QStyledItemDelegate::setModelData(baseEditor,model,index);
    }
    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const override
    {
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);
        editor->setGeometry(opt.rect);
        const QRect butRect = buttonRect(opt);
        QWidget* baseEditor = editor->findChild<QWidget*>("baseEditor");
        Q_ASSERT(baseEditor);
        baseEditor->setGeometry(0,0,opt.rect.width()-butRect.width(),opt.rect.height());
        QWidget* myButton = editor->findChild<QWidget*>("myButton");
        Q_ASSERT(myButton);
        myButton->setGeometry(opt.rect.width()-butRect.width(), 0, butRect.width(),butRect.height());
    }
    const QString text() const
    {
        return m_buttonText;
    }
    void setText(const QString &newButtonText)
    {
        m_buttonText = newButtonText;
        update();
    }
    const QIcon &icon() const
    {
        return m_buttonIcon;
    }
    void setIcon(const QIcon &newButtonIcon)
    {
        m_buttonIcon = newButtonIcon;
        update();
    }
    void setChecked(bool checked)
    {
        mIsChecked = checked;
    }
    bool isChecked()
    {
        return mIsChecked;
    }
    void setToolTip(QString tooltip)
    {
        tooltipText = tooltip;
    }
    void setDetailsButton(bool idb)
    {
        isDetailsButton = idb;
        update();
    }
    void setEnabled(bool enabled)
    {
        isEnabled = enabled;
        update();
    }
    void setHidden(bool hide)
    {
        isHidden = hide;
        isEnabled = ! hide;
        update();
    }
    void click()
    {
        mIsChecked = ! mIsChecked;
        clickedHelper();
    }
Q_SIGNALS:
    void clicked(const QModelIndex &index);
    void mouseIn(const QModelIndex &index);
protected:
    bool editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &option, const QModelIndex &index) override
    {
        Q_ASSERT(event);
        Q_ASSERT(model);
        Qt::ItemFlags flags = model->flags(index);
        if ((option.state & QStyle::State_Enabled) && (flags & Qt::ItemIsEnabled))
        {
            if (event->type() == QEvent::MouseButtonRelease)
            {
                QStyleOptionViewItem viewOpt(option);
                initStyleOption(&viewOpt, index);
                QMouseEvent *me = static_cast<QMouseEvent*>(event);
                if (me->button() == Qt::LeftButton)
                {
                    mIsChecked = ! mIsChecked;
                    currentIndex = index;
                    clickedHelper();
                }
            }
        }

        if (event->type() == QEvent::HoverEnter)
        {
            currentIndex = index;
            mouseInHelper();
        }
        
        return QStyledItemDelegate::editorEvent(event,model,option,index);
    }
    virtual QStyleOptionButton buttonOptions(const QStyleOptionViewItem &option, bool skipRct=false) const
    {
        const QWidget *widget = option.widget;
        QStyle *style = widget ? widget->style() : QApplication::style();
        int buttonIconSize = style->pixelMetric(QStyle::PM_ButtonIconSize, 0, widget);
        QStyleOptionButton buttonOption;
        buttonOption.text = m_buttonText;
        buttonOption.icon = m_buttonIcon;
        buttonOption.iconSize = (QSize(buttonIconSize,buttonIconSize));
        buttonOption.rect = skipRct ? QRect() : buttonRect(option);
        buttonOption.features = QStyleOptionButton::None;
        buttonOption.direction = option.direction;
        buttonOption.fontMetrics = option.fontMetrics;
        buttonOption.palette = option.palette;
        buttonOption.styleObject = option.styleObject;

        if(isEnabled)
            buttonOption.state = QStyle::State_Enabled;
        else
            buttonOption.state &= ~QStyle::State_Enabled;

        return buttonOption;
    }
    virtual QRect buttonRect(const QStyleOptionViewItem &option) const
    {
        const QStyleOptionButton buttonOption = buttonOptions(option, true);
        const QWidget *widget = option.widget;
        QStyle *style = widget ? widget->style() : QApplication::style();
        QSize buttonSize = style->sizeFromContents(QStyle::CT_PushButton, &buttonOption, QSize(), widget);
        buttonSize.setWidth(qMin(buttonSize.width(),option.rect.width()/2));

        QRect r = option.rect;
        int x = isDetailsButton ? (r.left()+ r.width() - 10) : (r.center().x() - 6);
        int y = isDetailsButton ? r.top() : r.top() + 10;
        int s = isDetailsButton ? 10 : 1;

        return QRect(x, y, s, s);
    }
    virtual bool helpEvent(QHelpEvent *event, QAbstractItemView *view, const QStyleOptionViewItem &option, const QModelIndex &index) override
    {
        if( !event || !view )
            return false;

        if( event->type() == QEvent::ToolTip )
        {
            QVariant tooltip = index.data( Qt::DisplayRole );
            if( QApplication::keyboardModifiers() == Qt::AltModifier )
            {
                QToolTip::showText( event->globalPos(), tooltipText);
            }
            else
            {
                QToolTip::showText( event->globalPos(), tooltipText);
            }

            if( !QStyledItemDelegate::helpEvent( event, view, option, index ) )
                QToolTip::hideText();
            return true;
        }

        return QStyledItemDelegate::helpEvent( event, view, option, index );
    }
private:
    mutable QModelIndex currentIndex;
    QPainter* mPainter;
    QString m_buttonText;
    QIcon m_buttonIcon;
    bool mIsChecked;
    bool isDetailsButton;
    bool isEnabled;
    bool isHidden;
    QString tooltipText;
    QTableWidget* tableWidget;

    void clickedHelper()
    {
        clicked(currentIndex);
    }
    void mouseInHelper()
    {
        mouseIn(currentIndex);
    }
};
#endif // BUTTONDELEGATE_H

tableWidgetDelegate.h

#ifndef TABLEWIDGETDELEGATE_H
#define TABLEWIDGETDELEGATE_H

#include <QTableWidget>
#include <QEvent>
#include <QModelIndex>
#include <QStyleOptionViewItem>
#include <QHoverEvent>

class TableWidgetDelegate : public QTableWidget
{
    Q_OBJECT
#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0)
    Q_DISABLE_COPY_MOVE(TableWidgetDelegate)
#else
    Q_DISABLE_COPY(TableWidgetDelegate)
#endif
public:
    explicit TableWidgetDelegate(QWidget *parent = Q_NULLPTR)
        : QTableWidget(parent)
    {}
protected:
    bool viewportEvent(QEvent *event) override
    {
        switch (event->type())
        {
        case QEvent::HoverMove:
        case QEvent::HoverEnter:
        case QEvent::HoverLeave:
        case QEvent::MouseMove:
        {
#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
            QModelIndex index = indexAt(static_cast<QHoverEvent*>(event)->position().toPoint());
            QStyleOptionViewItem options;
            initViewItemOption(&options);
#else
            QModelIndex index = indexAt(static_cast<QHoverEvent*>(event)->pos());
            QStyleOptionViewItem options = viewOptions();
#endif
            qDebug() << "QTableWidget -- viewport";

            QModelIndex buddy = model()->buddy(index);
            options.rect = visualRect(buddy);
            options.state |= (buddy == currentIndex() ? QStyle::State_HasFocus : QStyle::State_None);
            QAbstractItemDelegate *delegate = itemDelegateForIndex(index);
            delegate->editorEvent(event, model(), options, buddy);
            break;
        }
        default:
            break;
        }
        return QAbstractItemView::viewportEvent(event);
    }
};
#endif // TABLEWIDGETDELEGATE_H