Develop Reference

Dynamically add QTableView to dynamically created tab pages (QTabWidget)

I am trying to have a series of QTableView created at runtime and added to newly created pages of a multipage QTabWidget.
All seems to go fine, but the QTableView don't show up.
The QTabWidget gets zeroed (reset to no pages) and refurbished (...) flawlessly (at least it looks like so) depending on the selection of a combobox (and the dictionaries therein related).
I am also using a delegate callback to include a column of checkboxes to the QTableView (thanks to https://stackoverflow.com/a/50314085/7710452), which works fine stand alone.
Here is the code.
Main Window
EDIT
as recommended by eyllanesc, here is the standalone module (jump to the end of the post for details on the part I think is problematic):
"""
qt5 template
"""
import os
import sys
from PyQt5 import QtWidgets as qtw
from PyQt5 import QtCore as qtc
from PyQt5 import QtGui as qtg
from PyQt5 import uic
from configparser import ConfigParser, ExtendedInterpolation
from lib.SearchControllers import findGuis, get_controller_dict, show_critical, show_exception
import resources.resources
from lib.CheckBoxesDelegate import CheckBoxDelegate
myForm_2, baseClass = uic.loadUiType('./forms/setup.ui')
class MainWindow(baseClass):
def __init__(self, config_obj: ConfigParser,
config_name: str,
proj_name: str,
*args,
**kwargs):
super().__init__(*args, **kwargs)
self.ui = myForm_2()
self.ui.setupUi(self)
# your code begins here
self.setWindowTitle(proj_name + " Setup")
self.ui.logo_lbl.setPixmap(qtg.QPixmap(':/logo_Small.png'))
self.config_obj = config_obj
self.config_name = config_name
self.proj_filename = proj_name
self.proj_config = ConfigParser(interpolation=ExtendedInterpolation())
self.proj_config.read(proj_name)
self.guis_dict = {}
self.components = {}
self.cdp_signals = {}
self.root_path = self.config_obj['active']['controllers']
self.tableViews = []
self.tabs = []
self.iniControllersBox()
self.setActSignals()
self.load_bulk()
self.set_signals_table()
self.update_CurController_lbl()
self.update_ControllersTab() # here is where the action gets hot
# your code ends here
self.show() # here crashes if I passed the new tab to the instance of
# QTabView. otherwise it shows empty tabs
#########################################################
def load_bulk(self):
# get the list of running components into a dictionary
for i in self.list_controllers:
i_path = os.path.join(self.root_path, i)
print(i)
self.components[i] = get_controller_dict(i_path,
self.config_obj,
'Application.xml',
'Subcomponents/Subcomponent',
'Name',
'src')
for j in self.components[i]:
print(j)
signals_key = (i , j)
tgt = os.path.join(self.root_path, self.components[i][j])
self.cdp_signals[signals_key] = get_controller_dict(i_path,
self.config_obj,
self.components[i][j],
'Signals/Signal',
'Name',
'Type',
'Routing')
def set_signals_table(self):
self.ui.MonitoredDevicesTable.setHorizontalHeaderItem(0, qtw.QTableWidgetItem('GUI caption'))
self.ui.MonitoredDevicesTable.setHorizontalHeaderItem(1, qtw.QTableWidgetItem('Monitored Signal'))
def setActSignals(self):
self.ui.controllersBox.currentIndexChanged.connect(self.update_guis_list)
self.ui.controllersBox.currentIndexChanged.connect(self.update_CurController_lbl)
self.ui.controllersBox.currentIndexChanged.connect(self.update_ControllersTab)
def update_ControllersTab(self):
self.ui.componentsTab.clear() # this is the QTabWidget
self.tabs = []
self.tableViews = []
curr_controller = self.ui.controllersBox.currentText()
for i in self.components[curr_controller]:
if len(self.cdp_signals[curr_controller, i]) == 0:
continue
self.tabs.append(qtw.QWidget())
tabs_index = len(self.tabs) - 1
header_labels = ['', 'Signal', 'Type', 'Routing', 'Input']
model = qtg.QStandardItemModel(len(self.cdp_signals[curr_controller, i]), 5)
model.setHorizontalHeaderLabels(header_labels)
# in the next line I try to create a new QTableView passing
# the last tab as parameter, in the attempt to embed the QTableView
# into the QWidget Tab
self.tableViews.append(qtw.QTableView(self.tabs[tabs_index]))
tbw_Index = len(self.tableViews) - 1
self.tableViews[tbw_Index].setModel(model)
delegate = CheckBoxDelegate(None)
self.tableViews[tbw_Index].setItemDelegateForColumn(0, delegate)
rowCount = 0
for row in self.cdp_signals[curr_controller, i]:
for col in range(len(self.cdp_signals[curr_controller, i][row])):
index = model.index(rowCount, col, qtc.QModelIndex())
model.setData(index, self.cdp_signals[curr_controller, i][row][col])
try:
self.ui.componentsTab.addTab(self.tabs[tabs_index], i) # no problems, some controllers ask up to
except Exception as ex:
print(ex)
def update_CurController_lbl(self):
self.ui.active_controller_lbl.setText(self.ui.controllersBox.currentText())
def iniControllersBox(self):
self.list_controllers = [os.path.basename(f.path) for f in os.scandir(self.root_path) if f.is_dir() and str(
f.path).upper().endswith('NC')]
self.ui.controllersBox.addItems(self.list_controllers)
for i in range(self.ui.controllersBox.count()):
self.ui.controllersBox.setCurrentIndex(i)
newKey = self.ui.controllersBox.currentText()
cur_cntrlr = os.path.join(self.config_obj['active']['controllers'], self.ui.controllersBox.currentText())
self.guis_dict[newKey] = findGuis(cur_cntrlr, self.config_obj)
self.ui.controllersBox.setCurrentIndex(0)
self.update_guis_list()
def update_guis_list(self, index=0):
self.ui.GuisListBox.clear()
self.ui.GuisListBox.addItems(self.guis_dict[self.ui.controllersBox.currentText()])
if __name__ == '__main__':
config = ConfigParser()
config.read('./config.ini')
app = qtw.QApplication([sys.argv])
w = MainWindow(config, './config.ini',
'./test_setup_1.proj')
sys.exit(app.exec_())
and here the external to add the checkboxes column:
class CheckBoxDelegate(QtWidgets.QItemDelegate):
"""
A delegate that places a fully functioning QCheckBox cell of the column to which it's applied.
"""
def __init__(self, parent):
QtWidgets.QItemDelegate.__init__(self, parent)
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.
"""
self.drawCheck(painter, option, option.rect, QtCore.Qt.Unchecked if int(index.data()) == 0 else QtCore.Qt.Checked)
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 and this cell is editable. Otherwise do nothing.
'''
if not int(index.flags() & QtCore.Qt.ItemIsEditable) > 0:
return False
if event.type() == QtCore.QEvent.MouseButtonRelease and event.button() == QtCore.Qt.LeftButton:
# Change the checkbox-state
self.setModelData(None, model, index)
return True
if event.type() == QtCore.QEvent.MouseButtonPress or event.type() == QtCore.QEvent.MouseMove:
return False
return False
def setModelData (self, editor, model, index):
'''
The user wanted to change the old state in the opposite.
'''
model.setData(index, 1 if int(index.data()) == 0 else 0, QtCore.Qt.EditRole)
The 1st picture shows the layout in QTDesigner, the 2nd the result (emtpy tabs) when avoiding the crashing.
the QTabWidget has no problems in zeroing, or scale up, back to as many tab as I need, it's just that I have no clue on how to show the QTabview. My approach was to try to embed the QTabView in the tabpage passing it as parameter to the line creating the new QTabView.
Since I am using rather convoluted dictionaries, calling an XML parser to fill them up, not to mention the config files, I know even this version of my script is hardly reproduceable/runnable.
If someone had the patience of focusing on the update_ControllersTab method though, and tell me what I am doing wrong handling the QWidgets, it'd be great.
Again the basic idea is to clear the QTabWidget any time the user selects a different controller (combo box on the left):
self.ui.componentsTab.clear() # this is the QTabWidget
self.tabs = [] # list to hold QTabView QWidgets (pages) throughout the scope
self.tableViews = [] # list to hold QTabView(s) thorughout the scope
count how many tabs (pages) and hence embedded TabViews I need with the new controllers selected.
and then for each tab needed:
create a new tab (page)
self.tabs.append(qtw.QWidget())
tabs_index = len(self.tabs) - 1
create a new QTabView using a model:
header_labels = ['', 'Signal', 'Type', 'Routing', 'Input']
model = qtg.QStandardItemModel(len(self.cdp_signals[curr_controller, i]), 5)
model.setHorizontalHeaderLabels(header_labels)
self.tableViews.append(qtw.QTableView(self.tabs[tabs_index]))
tbw_Index = len(self.tableViews) - 1
self.tableViews[tbw_Index].setModel(model)
populate the TableView with data, and then finally add the tab widget (with the suppposedly embedded QTableView to the QTabWidget (the i argument is a string from my dbases Names:
self.ui.componentsTab.addTab(self.tabs[tabs_index], i)
This method is called also by the __init__ to initialize and apparently all goes error free, until the last 'init' statement:
`self.show()`
at which point the app crashes with:
Process finished with exit code 1073741845
on the other hand, if here instead of trying to embed the QTableView:
self.tableViews.append(qtw.QTableView(self.tabs[tabs_index]))
I omit the parameter, that is:
self.tableViews.append(qtw.QTableView())
the app doesn't crash anymore, but of course no QtableViews are shown, only empty tabpages:

As stupid as this may sound the problem is in... the delegate class that creates the checkboxes in the first column (see https://stackoverflow.com/a/50314085/7710452)
I commented out those two lines:
delegate = CheckBoxDelegate(None)
self.tableViews[tbw_Index].setItemDelegateForColumn(0, delegate)
and... bingo!
the CheckBoxDelegate works fine in the example shown in the post (a single QTableView form). I also tinkered around adding columns and rows, and moving the checkbox column back and forth with no problems. In that standalone. But as soon as I add the class and set the delegate, i am back at square zero, app crashing with:
Process finished with exit code 1073741845
so I am left with this problem now. Thnx to whomever read this.

Problem solved, see comment to post above.

Pass an instance via Context menu for QTableView and QTableWidget in PyQt

Uh, okay, friends, now I'm trying to add "export to Excel" feature for every table in my app like this:
...
def update_exportable_tables(self, *window):
"""
Please don't ask why, here 'I know what I'm doing'
"""
if not window:
window = self.window
for obj in window.__dict__:
objname = obj.title().lower()
the_object_itself = window.__dict__[obj]
if isinstance(the_object_itself, (QTableWidget, QTableView)):
the_object_itself.setContextMenuPolicy(Qt.CustomContextMenu)
the_object_itself.customContextMenuRequested.connect(self.TableContextEvent)
def TableContextEvent(self, event):
menu = QMenu()
excelAction = menu.addAction(u"Export to Excel")
excelAction.triggered.connect(self.export)
action = menu.exec_(QCursor.pos())
def export(self):
print 'Here I should do export'
...
Yeah, it works fine, but.... The question is how should I pass the clicked table instance to my export() function?

There are several different ways to solve this. Here's one way:
def update_exportable_tables(self):
for widget in QtGui.qApp.allWidgets():
if isinstance(widget, QTableView):
widget.setContextMenuPolicy(Qt.CustomContextMenu)
widget.customContextMenuRequested.connect(self.showContextMenu)
def showContextMenu(self, pos):
table = self.sender()
pos = table.viewport().mapToGlobal(pos)
menu = QtGui.QMenu()
excelAction = menu.addAction("Export to Excel")
if menu.exec_(pos) is excelAction:
self.export(table)
def export(self, table):
print 'Here I should do export:', table
(NB: QTableWidget is a subclass of QTableView).

Okay, thanks to Eli Bendersky, I googled one way to do it.
if isinstance(the_object_itself, (QTableWidget, QTableView)):
the_object_itself.setContextMenuPolicy(Qt.CustomContextMenu)
tricky = lambda: self.TableContextEvent(the_object_itself)
the_object_itself.customContextMenuRequested.connect(tricky)
...
def TableContextEvent(self, table_instance):
print table_instance
# ^^^^^^^^^^^^^ And yes, we have it!
upd1: It's still wrong, due connecting to only one instance (only last table instance is passed everywhere)

Accessing property of dynamically created QStandardItems in PyQt5

I'm having a problem determining whether or not the checkboxes that are dynamically created have been checked or unchecked by the user in a simple GUI I've created.
I've adapted the relevant code and pasted it below. Although it may be easy to just create and name 4 QStandardItems, I'm dealing with many lists containing many different items that change quite a lot, so it isn't really feasible to create them myself.
Any help finding out how to access these properties would be much appreciated.
from PyQt5.QtWidgets import *
from PyQt5.QtGui import *
class Splash(QWidget):
def __init__(self):
super().__init__()
# imagine this is a very long list...
self.seasons = ['summer','autumn','winter','spring']
self.initUI()
def initUI(self):
layout = QVBoxLayout()
list = QListView()
model = QStandardItemModel()
list.setModel(model)
printbtn = QPushButton('print values')
printbtn.clicked.connect(self.print_action)
for season in self.seasons:
item = QStandardItem(season)
item.setCheckable(True)
model.appendRow(item)
model.dataChanged.connect(lambda: self.print_action(item.text()))
layout.addWidget(printbtn)
layout.addWidget(list)
self.setLayout(layout)
self.show()
def print_action(self, item):
print('changed', item)
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
ex = Splash()
sys.exit(app.exec_())
In short - I can detect when an item has been checked using model.dataChanged and connecting that to a function, but it cannot differentiate between the seasons.

If you keep a reference to the list (or the model), you can search for the items by their text, and then get their check-state:
def print_action(self):
model = self.list.model()
for text in 'summer', 'autumn', 'winter', 'spring':
items = model.findItems(text)
if items:
checked = items[0].checkState() == Qt.Checked
print('%s = %s' % (text, checked))

It seems you want to get notified when the checkState of a item has been changed.
In my opinion, there are possible two ways.
First way, QModel will emit "dataChanged" to refresh the view, so you can connect the signal which means the checkState of a item might be changed.
model.dataChanged.connect(self.test)
def test(self):
pass
Second way, use a timer to notify yourself and you check it by yourselves.
timer = QTimer()
timer.timeout.connect(self.test)
timer.start(1000)

PySide: How Could I trigger the current clicked QPushbutton, not other later added

I am new to PySide. In my program, I encountered a problem that when I click one button, it triggers other button later added. Thanks!
self.addContentButton = QtGui.QPushButton('Add')
self.addContentButton.clicked.connect(self.addContent)
def addContent(self):
'''
slot to add a row that include a lineedit, combobox, two buttons
'''
self.contentTabHBoxWdgt = QtGui.QWidget()
self.contentName = QtGui.QLineEdit('line edit')
self.conetentTypeBox = QtGui.QComboBox()
self.conetentTypeBox.addItem('elem1')
self.conetentTypeBox.addItem('elem2')
self.contentSave = QtGui.QPushButton('save',parent = self.contentTabHBoxWdgt)
self.contentSave.clicked.connect(self.contntSaveAct)
self.contentDelete = QtGui.QPushButton('delete',parent=self.contentTabHBoxWdgt)
self.contentDelete.clicked.connect(self.contntDel)
self.contentTabHBox = QtGui.QHBoxLayout()
self.contentTabHBox.addWidget(self.contentName)
self.contentTabHBox.addWidget(self.conetentTypeBox)
self.contentTabHBox.addWidget(self.contentSave)
self.contentTabHBox.addWidget(self.contentDelete)
self.contentTabHBoxWdgt.setLayout(self.contentTabHBox)
self.contentTabVBox.addWidget(self.contentTabHBoxWdgt)
def contntDel(self):
'''
slot to delete a row
'''
msgBox = QtGui.QMessageBox(QtGui.QMessageBox.Warning, '', 'Be sure to delete')
okBttn = msgBox.addButton('Yes', QtGui.QMessageBox.AcceptRole)
noBttn = msgBox.addButton('Cancel', QtGui.QMessageBox.RejectRole)
ret = msgBox.exec_()
if msgBox.clickedButton() == okBttn:
self.contentTabVBox.removeWidget(self.contentDelete.parentWidget());
When I Add one row and click its delete button, it does not work as expected.While I add two or three row , I click one delete button , it remove one row that is not the clicked delete button belong to. How could I achieve this function. Ths!

Your problem is because you aren't really taking advantage of object oriented programming properly.
All rows in your example call the same instance of the method contntDel. This method uses self.contentDelete which always contains a reference to the last row added.
What you need to do is separate out everything related to a row to a new class. When you add a row, create a new instance of this class and pass in the contentTabVBox. That way each row (or instance of the new class you will write) will have it's own delete method.
Without a complete code example, I can't provide a complete solution, but this should give you a rough idea:
class MyRow(object):
def __init__(self,contentTabVBox, rows):
self.contentTabVBox = contentTabVBox
self.my_list_of_rows = rows
self.addContent()
def addContent(self):
# The code for your existing addContent method here
def contntDel(self):
# code from your existing contntDel function here
# also add (if Ok button clicked):
self.my_list_of_rows.remove(self)
class MyExistingClass(??whatever you have here normally??):
def __init__(....):
self.addContentButton = QtGui.QPushButton('Add')
self.addContentButton.clicked.connect(self.addContent)
self.my_list_of_rows = []
def addContent(self):
my_new_row = MyRow(self.contentTabVBox,self.my_list_of_rows)
# You mustsave a reference to my_new_row in a list or else it will get garbage collected.
self.my_list_of_rows.append(my_new_row)
Hope that helps!

Finding checked QRadioButton among many into a QVBoxLayout

I used the code below to dynamically create a group of radio buttons:
self.wPaymantType.qgbSomeSelectionGroup = QtGui.QGroupBox()
vbox = QtGui.QVBoxLayout()
for row in listOfChoices:
radio = QtGui.QRadioButton(row)
if bIsFirst:
radio.setChecked(True)
bIsFirst = False
if len(row.name) > nMaxLen:
nMaxLen = len(row.name)
vbox.addWidget(radio)
self.wPaymantType.qgbSomeSelectionGroup.setLayout(vbox)
How can I iterate through all radio buttons to find out which one is checked?
I tried something like this, but I didn't get anything good from it:
qvbl = self.qgbSomeSelectionGroup.children()[0]
for i in range(0, qvbl.count()):
child = qvbl.itemAt(i)
radio = QtGui.QRadioButton(child.widget())
if radio != None:
if radio.isChecked():
print "radio button num " + str(i) + " is checked"

Your code is not minimal and self-contained, so it's really hard to help you -- but I've anyway gone through the effort of building a near-minimal self-contained approximation of what you're trying to do and which does seem to work correctly -- here comes...:
from PyQt4 import QtGui
import sys
class MainWindow(QtGui.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.dowid()
self.setCentralWidget(self.thewid)
def dowid(self):
self.thewid = QtGui.QGroupBox()
vbox = QtGui.QVBoxLayout()
self.radiobuttons = []
listOfChoices = 'one two three'.split()
for i, row in enumerate(listOfChoices):
radio = QtGui.QRadioButton(row)
if i == 0:
radio.setChecked(True)
self.radiobuttons.append(radio)
vbox.addWidget(radio)
self.thewid.setLayout(vbox)
def examine(self):
for i, radio in enumerate(self.radiobuttons):
if radio.isChecked():
print "radio button num " + str(i) + " is checked"
else:
print "radio button num " + str(i) + " is NOT checked"
if __name__ == '__main__':
app = QtGui.QApplication([])
mainWin = MainWindow()
mainWin.show()
rc = app.exec_()
mainWin.examine()
This seems to do what you want. Key change is to keep the actual Python widget objects around rather than trying to restore them from the layout vbox -- that attempt seems to not be working as intended, at least as regards correct access to the crucial detail about whether a given radio button is checked or not, which is of course the heart of your Q.

I believe the reason why it's not working is your
radio = QtGui.QRadioButton(child.widget())
call at the code where you're checking if your checkbox is checked. I think what you're trying to do is typecast the child object to QtGui.QRadioButton and it doesn't work in this case. Instead you should be creating a new widget. Try changing it to smth. like this:
qvbl = self.qgbSomeSelectionGroup.layout()
for i in range(0, qvbl.count()):
widget = qvbl.itemAt(i).widget()
if (widget!=0) and (type(widget) is QtGui.QRadioButton):
if widget.isChecked():
print "radio button num " + str(i) + " is checked"
the code above should be iterating through child objects of the layout object, check their type and print "radio button..." in case it's radio buttong and it's checked
hope this helps, regards

I guess a better way to identify which button is checked is to use a QButtonGroup, as it provides a container to organize groups of button widgets. It is not a visual object, so it doesn't substitute the layout for visually arranging your radio buttons, but it does allow you to make them mutually exclusive and associate an integer "id" with them, letting you know which one is checked without the need to iterate through all the widgets present in the layout.
If you decide to use it, your code should turn into something like this:
self.wPaymantType.qgbSomeSelectionGroup = QtGui.QGroupBox()
vbox = QtGui.QVBoxLayout()
radioGroup = QtGui.QButtonGroup()
radioGroup.setExclusive(True)
for i,row in enumerate(listOfChoices):
radio = QtGui.QRadioButton(row)
radioGroup.addButton(radio, i)
if bIsFirst:
radio.setChecked(True)
bIsFirst = False
if len(row.name) > nMaxLen:
nMaxLen = len(row.name)
vbox.addWidget(radio)
self.wPaymantType.qgbSomeSelectionGroup.setLayout(vbox)
To identify the checked button, you can use QButtonGroup's checkedId method:
buttonId = radioGroup.checkedId()
or if you want to retrive the button object itself you can use the checkedButton method:
button = radioGroup.checkedButton()