我正在使用 QTableView 的复选框标记 Qt::ItemIsUserCheckable 来在表格单元格中显示复选框。
尝试通过阅读有关对齐方式的一些内容来居中显示单元格中的复选框，因此我从模型的 data() 函数返回 Qt::AlignCenter 作为 TextAlignmentRole。
QVariant ExampleModel::data(const QModelIndex &index, int role) const
{
if(!index.isValid())
return QVariant();
if (role == Qt::TextAlignmentRole)
return Qt::AlignCenter | Qt::AlignVCenter;
}
然而这并没有对齐我的复选框。
有人知道如何在此模式下对齐复选框吗？
editorEvent处理鼠标和键盘事件，同时设置具有适当状态的模型。void drawCheck(QPainter* painter, QStyleOptionViewItem const& option, QRect const& rect, Qt::CheckState state) const
并且
bool editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &option, const QModelIndex &index)
同时可以参考这个类似的问题链接...
Python（PySide，PyQt）的解决方案以使复选框居中，并允许进行编辑：
class BooleanDelegate(QItemDelegate):
def __init__(self, *args, **kwargs):
super(BooleanDelegate, self).__init__(*args, **kwargs)
def paint(self, painter, option, index):
# Depends on how the data function of your table model is implemented
# 'value' should recive a bool indicate if the checked value.
value = index.data(Qt.CheckStateRole)
self.drawCheck(painter, option, option.rect, value)
self.drawFocus(painter, option, option.rect)
def editorEvent(self, event, model, option, index):
if event.type() == QEvent.MouseButtonRelease:
value = bool(model.data(index, Qt.CheckStateRole))
model.setData(index, not value)
event.accept()
return super(BooleanDelegate, self).editorEvent(event, model, option, index)
class MyTableModel(QAbstractTableModel):
...
def flags(self, index):
if not index.isValid():
return Qt.ItemIsEnabled
if index.column() in self.columns_boolean:
return Qt.ItemIsEnabled | Qt.ItemIsUserCheckable
return Qt.ItemFlags(QAbstractTableModel.flags(self, index) | Qt.ItemIsEditable)
最后，在您的表格中设置BooleanDelagate
self.boolean_delegate = BooleanDelegate()
self.input_gui.setItemDelegateForColumn(5, self.boolean_delegate)
也许不是你想要的答案，但我发现在使用qtableviews时，实现自己的复选框项目代理要容易得多。
TextAlignmentRole确实是它所说的意思。不幸的是，正如您可能已经注意到的那样，似乎没有可用的图标/小部件对齐角色。
错误报告：http://bugreports.qt-project.org/browse/QTBUG-9047
同样的问题有一些答案：http://lists.trolltech.com/qt-interest/2006-06/msg00476.html
class CenteredCheckboxDelegate final : public QStyledItemDelegate
{
public:
using QStyledItemDelegate::QStyledItemDelegate;
void paint(QPainter * painter, const QStyleOptionViewItem & o, const QModelIndex & index ) const override
{
auto option2 = o;
initStyleOption(&option2, index);
auto * widget = option2.widget;
auto * style = widget ? widget->style() : QApplication::style();
// Turn off all features and just draw the background
option2.state.setFlag(QStyle::State_HasFocus, false);
option2.features.setFlag(QStyleOptionViewItem::HasDisplay, false);
option2.features.setFlag(QStyleOptionViewItem::HasDecoration, false);
option2.features.setFlag(QStyleOptionViewItem::HasCheckIndicator, false);
style->drawControl(QStyle::CE_ItemViewItem, &option2, painter, widget);
// Then just draw the a checkbox centred in the cell
option2.rect = getCheckboxRect(option2);
auto stateFlag = option2.checkState == Qt::Checked ? QStyle::State_On : QStyle::State_Off;
option2.state.setFlag(stateFlag, true);
style->drawPrimitive(QStyle::PE_IndicatorViewItemCheck, &option2, painter, widget);
}
bool editorEvent(QEvent * event, QAbstractItemModel * model, const QStyleOptionViewItem & option, const QModelIndex & index) override
{
auto flags = index.flags();
if (!flags.testFlag(Qt::ItemIsUserCheckable) || !flags.testFlag(Qt::ItemIsEnabled))
{
return false;
}
if(event->type() == QEvent::MouseButtonRelease)
{
auto * mouseEvent = static_cast<QMouseEvent*>(event);
bool mouseOverCheckbox = getCheckboxRect(option).contains(mouseEvent->pos());
if(!mouseOverCheckbox) return false;
}
else if(event->type() == QEvent::KeyPress)
{
auto * keyEvent = static_cast<QKeyEvent*>(event);
if(keyEvent->key() != Qt::Key_Space) return false;
}
else
{
return false;
}
auto checkState = index.data(Qt::CheckStateRole).value<Qt::CheckState>();
auto toggledCheckState = checkState == Qt::Checked ? Qt::Unchecked : Qt::Checked;
return model->setData(index, toggledCheckState, Qt::CheckStateRole);
}
private:
QRect getCheckboxRect(const QStyleOptionViewItem & option) const
{
auto * widget = option.widget;
auto * style = widget ? widget->style() : QApplication::style();
auto checkboxSize = style->subElementRect(QStyle::SE_CheckBoxIndicator, &option, widget).size();
return QStyle::alignedRect(option.direction, Qt::AlignCenter, checkboxSize, option.rect);
}
};
基于Parker Coates惊人的C++版本，使用PyQt5 / Pyside2版本
class QTableviewEditableDelegate(QStyledItemDelegate):
def __init__(self, alignment: Qt.Alignment, parent: Optional[QWidget] = None):
super().__init__(parent)
self.alignment: Qt.Alignment = alignment
self.parent = parent
if self.parent:
self.style = self.parent.style()
else:
self.style = QApplication.style()
def editorEvent(self, event: QMouseEvent, model: QAbstractItemModel, option: QStyleOptionViewItem,
index: QModelIndex) -> bool:
checkbox_data = index.data(Qt.CheckStateRole)
flags = index.flags()
if not (flags & Qt.ItemIsUserCheckable) or not (flags & Qt.ItemIsEnabled) or checkbox_data is None:
return False
else:
if event.type() == QEvent.MouseButtonRelease:
mouseover_checkbox: bool = self.get_checkbox_rect(option).contains(event.pos())
if not mouseover_checkbox:
return False
elif event.type() == QEvent.KeyPress and event.key() != Qt.Key_Space:
return False
else:
return False
if checkbox_data == Qt.Checked:
checkbox_toggled: int = Qt.Unchecked
else:
checkbox_toggled: int = Qt.Checked
return model.setData(index, checkbox_toggled, Qt.CheckStateRole)
def get_checkbox_rect(self, option: QStyleOptionViewItem) -> QRect:
widget = option.widget
if widget:
style = widget.style()
else:
style = self.style()
checkbox_size: QSize = style.subElementRect(QStyle.SE_CheckBoxIndicator, option, widget).size()
return QStyle.alignedRect(option.direction, Qt.AlignCenter, checkbox_size, option.rect)
def paint(self, painter: QPainter, option: QStyleOptionViewItem, index: QModelIndex):
try:
self.initStyleOption(option, index)
painter.save()
flags: Qt.ItemFlags = index.model().flags(index)
widget: Optional[QWidget] = option.widget
checkbox_data = index.data(Qt.CheckStateRole)
if widget:
style = widget.style()
else:
style = self.style()
if option.HasCheckIndicator and checkbox_data is not None:
option_checkbox = option
self.initStyleOption(option_checkbox, index)
option_checkbox.state = option_checkbox.state & ~QStyle.State_HasFocus
option_checkbox.features = option_checkbox.features & ~QStyleOptionViewItem.HasDisplay
option_checkbox.features = option_checkbox.features & ~QStyleOptionViewItem.HasDecoration
option_checkbox.features = option_checkbox.features & ~QStyleOptionViewItem.HasCheckIndicator
style.drawControl(QStyle.CE_ItemViewItem, option_checkbox, painter, widget)
# Then just draw the a checkbox centred in the cell
option_checkbox.rect = self.get_checkbox_rect(option_checkbox)
if option_checkbox.checkState == Qt.Checked:
state_flag = QStyle.State_On
else:
state_flag = QStyle.State_Off
option_checkbox.state = option_checkbox.state | state_flag
style.drawPrimitive(QStyle.PE_IndicatorViewItemCheck, option_checkbox, painter, widget)
else:
QStyledItemDelegate.paint(self, painter, option, index)
painter.restore()
except Exception as e:
print(repr(e))