We are using a QTableView with Qt 4.6.3, and need a column that only has a checkbox in each cell. We're using a custom subclass of QAbstractTableModel as the model for the QTableView. Right now, we have a checkbox by setting the Qt::ItemIsUserCheckable flag. But we can't figure out how to get rid of the blank textbox next to the checkbox!
How can we make the column only have a checkbox, nothing else?
Here is a solution. For this to work properly, your column should not have the Qt::ItemIsEditable or Qt::ItemIsUserCheckable flags set. This reads the boolean values from Qt::DisplayRole and calls setData() with Qt::EditRole (i.e. not Qt::CheckStateRole.)
#include "check_box_delegate.h" #include #include static QRect CheckBoxRect(const QStyleOptionViewItem &view_item_style_options) { QStyleOptionButton check_box_style_option; QRect check_box_rect = QApplication::style()->subElementRect( QStyle::SE_CheckBoxIndicator, &check_box_style_option); QPoint check_box_point(view_item_style_options.rect.x() + view_item_style_options.rect.width() / 2 - check_box_rect.width() / 2, view_item_style_options.rect.y() + view_item_style_options.rect.height() / 2 - check_box_rect.height() / 2); return QRect(check_box_point, check_box_rect.size()); } CheckBoxDelegate::CheckBoxDelegate(QObject *parent) : QStyledItemDelegate(parent) { } void CheckBoxDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const { bool checked = index.model()->data(index, Qt::DisplayRole).toBool(); QStyleOptionButton check_box_style_option; check_box_style_option.state |= QStyle::State_Enabled; if (checked) { check_box_style_option.state |= QStyle::State_On; } else { check_box_style_option.state |= QStyle::State_Off; } check_box_style_option.rect = CheckBoxRect(option); QApplication::style()->drawControl(QStyle::CE_CheckBox, &check_box_style_option, painter); } // This is essentially copied from QStyledItemEditor, except that we // have to determine our own "hot zone" for the mouse click. bool CheckBoxDelegate::editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &option, const QModelIndex &index) { if ((event->type() == QEvent::MouseButtonRelease) || (event->type() == QEvent::MouseButtonDblClick)) { QMouseEvent *mouse_event = static_cast(event); if (mouse_event->button() != Qt::LeftButton || !CheckBoxRect(option).contains(mouse_event->pos())) { return false; } if (event->type() == QEvent::MouseButtonDblClick) { return true; } } else if (event->type() == QEvent::KeyPress) { if (static_cast(event)->key() != Qt::Key_Space && static_cast(event)->key() != Qt::Key_Select) { return false; } } else { return false; } bool checked = index.model()->data(index, Qt::DisplayRole).toBool(); return model->setData(index, !checked, Qt::EditRole); } Note: The answer of Dave works also for Python using PySide or PyQt4. I translated it, and it works great. Additionally, I added the functionality that the checkbox does not accept user input and is shown in a ReadOnly state if the cell is not editable. Thanks Dave for your code!
class CheckBoxDelegate(QStyledItemDelegate): def createEditor(self, parent, option, index): ''' Important, otherwise an editor is created if the user clicks in this cell. ''' return None def paint(self, painter, option, index): ''' Paint a checkbox without the label. ''' checked = bool(index.model().data(index, Qt.DisplayRole)) check_box_style_option = QStyleOptionButton() if (index.flags() & Qt.ItemIsEditable) > 0: check_box_style_option.state |= QStyle.State_Enabled else: check_box_style_option.state |= QStyle.State_ReadOnly if checked: check_box_style_option.state |= QStyle.State_On else: check_box_style_option.state |= QStyle.State_Off check_box_style_option.rect = self.getCheckBoxRect(option) if not index.model().hasFlag(index, Qt.ItemIsEditable): check_box_style_option.state |= QStyle.State_ReadOnly QApplication.style().drawControl(QStyle.CE_CheckBox, check_box_style_option, painter) def editorEvent(self, event, model, option, index): ''' Change the data in the model and the state of the checkbox if the user presses the left mousebutton or presses Key_Space or Key_Select and this cell is editable. Otherwise do nothing. ''' if not (index.flags() & Qt.ItemIsEditable) > 0: return False # Do not change the checkbox-state if event.type() == QEvent.MouseButtonRelease or event.type() == QEvent.MouseButtonDblClick: if event.button() != Qt.LeftButton or not self.getCheckBoxRect(option).contains(event.pos()): return False if event.type() == QEvent.MouseButtonDblClick: return True elif event.type() == QEvent.KeyPress: if event.key() != Qt.Key_Space and event.key() != Qt.Key_Select: return False else: return False # Change the checkbox-state self.setModelData(None, model, index) return True def setModelData (self, editor, model, index): ''' The user wanted to change the old state in the opposite. ''' newValue = not bool(index.model().data(index, Qt.DisplayRole)) model.setData(index, newValue, Qt.EditRole) def getCheckBoxRect(self, option): check_box_style_option = QStyleOptionButton() check_box_rect = QApplication.style().subElementRect(QStyle.SE_CheckBoxIndicator, check_box_style_option, None) check_box_point = QPoint (option.rect.x() + option.rect.width() / 2 - check_box_rect.width() / 2, option.rect.y() + option.rect.height() / 2 - check_box_rect.height() / 2) return QRect(check_box_point, check_box_rect.size()) They had the same issue at qtcentre. There they came to a solution with delegates, maybe you should have a look at those.