How to create a combobox of checkboxes ?

[JonB]

@EJWA
But you need to understand that a combo box is only for selection of one item, do you want one item or multiple items to be selectable?

If it's multiple items but you don't like how much space a listbox takes up, you must make the listbox height smaller.

[A Former User]

I tried this example found in internet and it works :

from PyQt4 import QtGui, QtCore
import sys, os

class CheckableComboBox(QtGui.QComboBox):
    def __init__(self):
        super(CheckableComboBox, self).__init__()
        self.view().pressed.connect(self.handleItemPressed)
        self.setModel(QtGui.QStandardItemModel(self))

    def handleItemPressed(self, index):
        item = self.model().itemFromIndex(index)
        if item.checkState() == QtCore.Qt.Checked:
            item.setCheckState(QtCore.Qt.Unchecked)
        else:
            item.setCheckState(QtCore.Qt.Checked)

class Dialog_01(QtGui.QMainWindow):
    def __init__(self):
        super(QtGui.QMainWindow,self).__init__()
        myQWidget = QtGui.QWidget()
        myBoxLayout = QtGui.QVBoxLayout()
        myQWidget.setLayout(myBoxLayout)
        self.setCentralWidget(myQWidget)
        self.ComboBox = CheckableComboBox()
        for i in range(3):
            self.ComboBox.addItem("Combobox Item " + str(i))
            item = self.ComboBox.model().item(i, 0)
            item.setCheckState(QtCore.Qt.Unchecked)
        self.toolbutton = QtGui.QToolButton(self)
        self.toolbutton.setText('Select Categories ')
        self.toolmenu = QtGui.QMenu(self)
        for i in range(3):
            action = self.toolmenu.addAction("Category " + str(i))
            action.setCheckable(True)
        self.toolbutton.setMenu(self.toolmenu)
        self.toolbutton.setPopupMode(QtGui.QToolButton.InstantPopup)
        myBoxLayout.addWidget(self.toolbutton)
        myBoxLayout.addWidget(self.ComboBox)

if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    dialog_1 = Dialog_01()
    dialog_1.show()
    dialog_1.resize(480,320)
    sys.exit(app.exec_())

[jsulm]

@EJWA A list box does not have to be big: it will have a scroll bar if not all entries can be shown at the same time. Adding checkboxes to a combo box could irritate users as it a combo box is there to select one item from n, not m items from n.

[A Former User]

Hello again,

If I understand there is no solution to do a combobox with checkboxes even like this example :

from PyQt4 import QtGui, QtCore
import sys, os

class CheckableComboBox(QtGui.QComboBox):
    def __init__(self):
        super(CheckableComboBox, self).__init__()
        self.view().pressed.connect(self.handleItemPressed)
        self.setModel(QtGui.QStandardItemModel(self))

    def handleItemPressed(self, index):
        item = self.model().itemFromIndex(index)
        if item.checkState() == QtCore.Qt.Checked:
            item.setCheckState(QtCore.Qt.Unchecked)
        else:
            item.setCheckState(QtCore.Qt.Checked)

class Dialog_01(QtGui.QMainWindow):
    def __init__(self):
        super(QtGui.QMainWindow,self).__init__()
        myQWidget = QtGui.QWidget()
        myBoxLayout = QtGui.QVBoxLayout()
        myQWidget.setLayout(myBoxLayout)
        self.setCentralWidget(myQWidget)
        self.ComboBox = CheckableComboBox()
        for i in range(3):
            self.ComboBox.addItem("Combobox Item " + str(i))
            item = self.ComboBox.model().item(i, 0)
            item.setCheckState(QtCore.Qt.Unchecked)
        self.toolbutton = QtGui.QToolButton(self)
        self.toolbutton.setText('Select Categories ')
        self.toolmenu = QtGui.QMenu(self)
        for i in range(3):
            action = self.toolmenu.addAction("Category " + str(i))
            action.setCheckable(True)
        self.toolbutton.setMenu(self.toolmenu)
        self.toolbutton.setPopupMode(QtGui.QToolButton.InstantPopup)
        myBoxLayout.addWidget(self.toolbutton)
        myBoxLayout.addWidget(self.ComboBox)

if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    dialog_1 = Dialog_01()
    dialog_1.show()
    dialog_1.resize(480,320)
    sys.exit(app.exec_())

[mrjj]

@EJWA
The main issue is that it will close when you Check one item.
If you hax that, you then have the issue of how to close it.

So overall as @jsulm says, its not a very good idea as
it breaks the standard for the operating system.

Unless you mean, you just want user to check one and then its fine it closes.

[A Former User]

So, it means that there is no solution other than using a list widget which can be open when you select multiple elements ?

[mrjj]

@EJWA
well you can hax it if you really feel like it

from PyQt4 import QtCore, QtGui    
app = QtGui.QApplication([])

class Combo(QtGui.QComboBox):
    def __init__(self, *args, **kwargs):
        super(Combo, self).__init__()
        self.addItems(['Item_1','Item_2','Item_3','Item_4','Item_5'])
        self.show()

    def hidePopup (self):
        pass

inst=Combo()
sys.exit(app.exec_())

https://stackoverflow.com/questions/25733891/how-to-cause-qcombobox-pull-down-menu-to-stay-open

[A Former User]

Thanks very much. What about the tool button ? It is a good idea ?

 self.toolbutton = QtGui.QToolButton(self)
        self.toolbutton.setText('Select Categories ')
        self.toolmenu = QtGui.QMenu(self)
        for i in range(3):
            action = self.toolmenu.addAction("Category " + str(i))
            action.setCheckable(True)
        self.toolbutton.setMenu(self.toolmenu)
        self.toolbutton.setPopupMode(QtGui.QToolButton.InstantPopup)

[mrjj]

@EJWA

You mean to use toolbutton to popup menu ?
or toolbutton inside combo box ?

Using a popup menu might suffer from same issue to close when one is selected/checked.

[A Former User]

the same functions as using a combobox with checkboxes

[mrjj]

@EJWA

Both ways can work even if not usual function.

Also if its rare user need to select multiple Categories its maybe ok.

[A Former User]

Can I keep the toolbutton menu open when selecting multiple categories ?

[mrjj]

@EJWA

well yes but its more haxy than combo box
https://stackoverflow.com/questions/2050462/prevent-a-qmenu-from-closing-when-one-of-its-qaction-is-triggered/11571550#11571550
you might need to use event filter

Why dont u just use a dialog ?
Click button.
Dialog opens with ListView,
use checks one or more Categories.
User press ok to close.

[A Former User]

Hello, it seems that this code doesn't work because I design the interface with QT creator, so I must generate the py file from the ui using the pyuic4 and then modify the py file. I am trying now this example and I

class CheckableComboBox(QtGui.QComboBox):
    def __init__(self):
        super(CheckableComboBox, self).__init__()
        self.view().pressed.connect(self.handleItemPressed)
        self.setModel(QtGui.QStandardItemModel(self))

    def handleItemPressed(self, index):
        item = self.model().itemFromIndex(index)
        if item.checkState() == QtCore.Qt.Checked:
            item.setCheckState(QtCore.Qt.Unchecked)
        else:
            item.setCheckState(QtCore.Qt.Checked)
self.imploc_extension = CheckableComboBox()
      
        for i in range(4):
            self.imploc_extension.addItem("csv")
            self.imploc_extension.addItem("xls")
            self.imploc_extension.addItem("mtx")
            self.imploc_extension.addItem("txt")
            item = self.imploc_extension.model().item(i, 0)
            item.setCheckState(QtCore.Qt.Unchecked)

[jsulm]

@EJWA Modifying generated code isn't a good idea as your modifications will be lost next time the code is generated...

[A Former User]

Finally,

I will use listwidget, it us easier. Thank you for all your help.