Basically it is that the items are not selectable, since that is the event that triggers the closing of the popup so the solution is to eliminate that flag in the model as I did in a previous answer.
On the other hand the option to be checkeable does not come by default in the QSqlQueryModel, so we have to implement it for that we based on another previous answer.
Finally, a class is created that inherits from QComboBox and we overwrite the hidePopup() method to emit a signal that sends the selected items.
Update:
If you want to also be marked when you press any part of the item you must create a delegate and overwrite the editorEvent() method so that it handles the MouseButtonRelease event. But this brings a small problem: to open the popup you have to press the item that is displayed so it will open marked.
from PyQt5 import QtCore, QtGui, QtWidgets, QtSql
class CheckSqlQueryModel(QtSql.QSqlQueryModel):
def __init__(self, *args, **kwargs):
QtSql.QSqlQueryModel.__init__(self, *args, **kwargs)
self.checks = {}
def checkState(self, pindex):
if pindex not in self.checks.keys():
self.checks[pindex] = QtCore.Qt.Unchecked
return self.checks[pindex]
def data(self, index, role=QtCore.Qt.DisplayRole):
if role == QtCore.Qt.CheckStateRole and index.isValid():
return self.checkState(QtCore.QPersistentModelIndex(index))
return QtSql.QSqlQueryModel.data(self, index, role)
def setData(self, index, value, role=QtCore.Qt.EditRole):
if role == QtCore.Qt.CheckStateRole and index.isValid():
self.checks[QtCore.QPersistentModelIndex(index)] = value
return True
return QtSql.QSqlQueryModel(self, index, value, role)
def flags(self, index):
fl = QtSql.QSqlQueryModel.flags(self, index) & ~QtCore.Qt.ItemIsSelectable
fl |= QtCore.Qt.ItemIsEditable | QtCore.Qt.ItemIsUserCheckable
return fl
class CheckComboBox(QtWidgets.QComboBox):
selectedChanged = QtCore.pyqtSignal(list)
def hidePopup(self):
results = []
for i in range(self.count()):
if self.itemData(i, QtCore.Qt.CheckStateRole) == QtCore.Qt.Checked:
results.append(self.itemText(i))
self.selectedChanged.emit(results)
QtWidgets.QComboBox.hidePopup(self)
class CheckDelegate(QtWidgets.QStyledItemDelegate):
def editorEvent(self, event, model, option, index):
if event.type() == QtCore.QEvent.MouseButtonRelease:
val = index.data(QtCore.Qt.CheckStateRole)
new_val = QtCore.Qt.Checked if val == QtCore.Qt.Unchecked else QtCore.Qt.Unchecked
model.setData(index, new_val, QtCore.Qt.CheckStateRole)
return True
return QtWidgets.QStyledItemDelegate.editorEvent(self, event, model, option, index)
class Widget(QtWidgets.QWidget):
def __init__(self, *args, **kwargs):
QtWidgets.QWidget.__init__(self, *args, **kwargs)
lay = QtWidgets.QVBoxLayout(self)
combo = CheckComboBox()
combo.setView(QtWidgets.QListView())
combo.setItemDelegate(CheckDelegate(combo))
model = CheckSqlQueryModel()
model.setQuery("SELECT name FROM categories")
combo.setModel(model)
self.lw = QtWidgets.QListWidget()
combo.selectedChanged.connect(self.on_selectedChanged)
lay.addWidget(combo)
lay.addWidget(self.lw)
def on_selectedChanged(self, items):
self.lw.clear()
self.lw.addItems(items)
def createConnection():
db = QtSql.QSqlDatabase.addDatabase("QSQLITE")
db.setDatabaseName(":memory:")
if not db.open():
QtWidgets.QMessageBox.critical(None, "Cannot open database",
"Unable to establish a database connection.\n"
"This example needs SQLite support. Please read "
"the Qt SQL driver documentation for information how "
"to build it.\n\n"
"Click Cancel to exit.", QMessageBox.Cancel)
return False
query = QtSql.QSqlQuery()
query.exec_("create table categories (id int primary key, name varchar(20))");
for i in range(1, 10):
query.exec_("insert into categories values({i}, 'categories-{i}')".format(i=i));
return True
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
if not createConnection():
sys.exit(-1)
w = Widget()
w.show()
sys.exit(app.exec_())
