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How to get model index children in QSortFilterProxyModel of QFileSystemModel?

I have a file system folder with wollowing structure on a Hard disk:
So, I want to see the the folliwing structure in my QTreeView:
I try to use QSortFilterProxy model to do that.
My strategy:
identify 'Folder_1' item in filterAcceptsRow and decline insertion of 'Folder_1' and its children
recursively get children of 'Folder_1' (because it can has another folders)
insert children instead of 'Folder_1'
So, I stuck on step 2.
Is my strategy right?
How to get children of parent item in filterAcceptsRow ?
Do I have to use another method to do that?
Where (instance and method) I should do children insertion (step 3)?
import sys
from PyQt5 import QtWidgets
from PyQt5.QtCore import QSortFilterProxyModel
class MyFilterModel(QSortFilterProxyModel):
def __init__(self, *args, **kwargs):
super(MyFilterModel, self).__init__(*args, **kwargs)
def filterAcceptsRow(self, sourceRow, sourceParent):
index = self.sourceModel().index(sourceRow, 0, sourceParent)
print('data =', index.data())
if index.data() == 'Folder_1':
child_index = self.sourceModel().index(sourceRow+1, 0, sourceParent)
print(child_index.data())
rowCount = self.sourceModel().rowCount(index)
accepted = QSortFilterProxyModel.filterAcceptsRow(self, sourceRow,
sourceParent)
if rowCount > 0 and not accepted:
for row in range(rowCount):
if self.filterAcceptsRow(row, index):
return True
return accepted
class Myview(QtWidgets.QMainWindow):
def __init__(self, parent=None):
QtWidgets.QMainWindow.__init__(self)
self._root_path = r"C:\Users\Dmitriy.Kubarev\Documents\TEST_FILE_SYSTEM"
model = QtWidgets.QFileSystemModel()
sourceIndex = model.setRootPath(self._root_path)
proxy_model = MyFilterModel()
proxy_model.setSourceModel(model)
view = QtWidgets.QTreeView()
view.setModel(proxy_model)
central_widget = QtWidgets.QWidget()
main_layout = QtWidgets.QVBoxLayout()
button = QtWidgets.QPushButton('ok')
main_layout.addWidget(button)
main_layout.addWidget(view)
central_widget.setLayout(main_layout)
proxyIndex = proxy_model.mapFromSource(sourceIndex)
view.setRootIndex(proxyIndex)
self.setCentralWidget(central_widget)
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
myview = Myview()
myview.show()
sys.exit(app.exec_())

Alerting QDataWidgetMapper to changes when using a custom Model & Delegate

I'm using a subclassed QAbstractTableModel with dataclasses as items. Each dataclass contains a field "field1" with a list, which I'd like to display in a listview and have it automatically change whenever I edit or add an item in the listview.
To do that I set a custom delegate to the QDataWidgetMapper which will retrieve and set the values from that dataclass. This works the way I want it to.
My problem is that I want to add additional items to that listview with the press of a button and have the QDataWidgetMapper add them automatically to the model.
This is what I have so far:
import sys
import dataclasses
from typing import List, Any
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
#dataclasses.dataclass()
class StorageItem:
field1: List[str] = dataclasses.field(default_factory=list)
class StorageModel(QAbstractTableModel):
def __init__(self, parent=None):
super().__init__(parent)
test = StorageItem()
test.field1 = ['Item °1', 'Item °2']
self._data: List[StorageItem] = [test]
def data(self, index: QModelIndex, role: int = ...) -> Any:
if not index.isValid():
return
item = self._data[index.row()]
col = index.column()
if role in {Qt.DisplayRole, Qt.EditRole}:
if col == 0:
return item.field1
else:
return None
def setData(self, index: QModelIndex, value, role: int = ...) -> bool:
if not index.isValid() or role != Qt.EditRole:
return False
item = self._data[index.row()]
col = index.column()
if col == 0:
item.field1 = value
self.dataChanged.emit(index, index)
print(self._data)
return True
def flags(self, index: QModelIndex) -> Qt.ItemFlags:
return Qt.ItemFlags(
Qt.ItemIsEnabled | Qt.ItemIsSelectable | Qt.ItemIsEditable
)
def rowCount(self, parent=None) -> int:
return len(self._data)
def columnCount(self, parent=None) -> int:
return len(dataclasses.fields(StorageItem))
class TestDelegate(QStyledItemDelegate):
def __init__(self, parent=None):
super().__init__(parent)
def setEditorData(self, editor: QWidget, index: QModelIndex) -> None:
if isinstance(editor, QListView):
data = index.model().data(index, Qt.DisplayRole)
editor.model().setStringList(data)
else:
super().setEditorData(editor, index)
def setModelData(
self, editor: QWidget,
model: QAbstractItemModel,
index: QModelIndex
) -> None:
if isinstance(editor, QListView):
data = editor.model().stringList()
model.setData(index, data, Qt.EditRole)
else:
super().setModelData(editor, model, index)
class CustomListView(QListView):
item_added = pyqtSignal(name='itemAdded')
def __init__(self, parent=None):
super().__init__(parent)
self.setModel(QStringListModel())
def add_item(self, item: str):
str_list = self.model().stringList()
str_list.append(item)
self.model().setStringList(str_list)
self.item_added.emit()
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super().__init__(parent)
cent_widget = QWidget()
self.setCentralWidget(cent_widget)
# Vertical Layout
v_layout = QVBoxLayout()
v_layout.setContentsMargins(10, 10, 10, 10)
# Listview
self.listview = CustomListView()
v_layout.addWidget(self.listview)
# Button
self.btn = QPushButton('Add')
self.btn.clicked.connect(lambda: self.listview.add_item('New Item'))
v_layout.addWidget(self.btn)
cent_widget.setLayout(v_layout)
# Set Mapping
self.mapper = QDataWidgetMapper()
self.mapper.setItemDelegate(TestDelegate())
self.mapper.setSubmitPolicy(QDataWidgetMapper.AutoSubmit)
self.mapper.setModel(StorageModel())
self.mapper.addMapping(self.listview, 0)
self.mapper.toFirst()
self.listview.itemAdded.connect(self.mapper.submit)
def main():
app = QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec()
if __name__ == '__main__':
main()
Currently, I'm using the signal itemAdded from inside the custom ListView to manually submit the QDataWidgetMapper.
Is there a way to do this within CustomListView, without using a custom signal?
Somehow the delegate knows when data in the listview has been edited. How can I trigger that same mechanism when new items are added?

TL; DR; It can not.
The submitPolicy QDataWidgetMapper::AutoSubmit indicates that the model will be updated when focus is lost. The model is also updated when the commitData or closeEditor signal of the delegate is invoked, which happens by default when some specific keys are pressed.
A better implementation would be to create a signal that is emitted every time a change is made in the QListView model and connect it to submit, not just the method of adding elements. Also it is better to use a custom qproperty.
class CustomListView(QListView):
items_changed = pyqtSignal(name="itemsChanged")
def __init__(self, parent=None):
super().__init__(parent)
self.setModel(QStringListModel())
self.model().rowsInserted.connect(self.items_changed)
self.model().rowsRemoved.connect(self.items_changed)
self.model().dataChanged.connect(self.items_changed)
self.model().layoutChanged.connect(self.items_changed)
def add_item(self, item: str):
self.items += [item]
#pyqtProperty(list, notify=items_changed)
def items(self):
return self.model().stringList()
#items.setter
def items(self, data):
if len(data) == len(self.items) and all(
x == y for x, y in zip(data, self.items)
):
return
self.model().setStringList(data)
self.items_changed.emit()
# Set Mapping
self.mapper = QDataWidgetMapper()
self.mapper.setModel(StorageModel())
self.mapper.addMapping(self.listview, 0, b"items")
self.mapper.toFirst()
self.listview.items_changed.connect(self.mapper.submit)

Calling a model method through a subclass

What I'm trying to do, is to create a subclass of QTableView that will accept a standardized model (which is the result of a mysql query), and populate it. With it, I'd like to define a custom context menu which allows me to add or remove a row. This approach allows me to define the model and subclass once, and then call them both to populate them with a number of different queries without duplicating code.
The add_row and remove_row QActions would essentially call the model methods insertRows and removeRows.
Here's a functioning example (apart from the mariadb module which is separate):
from PySide2 import QtWidgets, QtCore, Qt, QtGui
import maria_db
import numpy
app = QtWidgets.QApplication([])
#Define model for tablePersonnel
class TableModel(QtCore.QAbstractTableModel):
def __init__(self, db,query,tableName,id):
super(TableModel, self).__init__()
self.db=db
self.query=query
self.tableName=tableName
self.id=id
self.pullData()
def pullData(self):
self.datasheet=self.db.RunQuery(self.query)
self.rows = numpy.array(self.datasheet.fetchall())
self.headers = numpy.array(self.datasheet.column_names)
self.idIndex=int(numpy.where(self.headers==self.id)[0])
def data(self, index, role):
if role == QtCore.Qt.DisplayRole:
return str(self.rows[index.row()][index.column()])
def rowCount(self, parent):
return len(self.rows)
def columnCount(self, parent):
return len(self.headers)
def headerData(self, section, orientation, role=QtCore.Qt.DisplayRole):
if orientation == QtCore.Qt.Horizontal and role == QtCore.Qt.DisplayRole:
return self.headers[section]
def flags(self,index):
if index.column()!=self.idIndex:
return QtCore.Qt.ItemIsEnabled | QtCore.Qt.ItemIsEditable | QtCore.Qt.ItemIsSelectable
else:
return QtCore.Qt.ItemIsSelectable
def setData(self, index,value,role=QtCore.Qt.EditRole):
if index.isValid():
sel_id=self.rows[index.row()][0]
sel_column=self.headers[index.column()]
if self.db.UpdateCell(self.tableName,sel_id,self.id,sel_column,value)==True:
self.rows[self.idFinder(self.rows,sel_id)][1]=value
self.dataChanged.emit(index,index)
return True
def insertRows(self):
print("inserting row!!!")
def removeRows(self):
pass
#find index of selected ID
def idFinder(self,data, search):
for i in range(len(data)):
for j in range(len(data[i])):
if data[i][j] == search:
return i
else:
return False
class EditTable(QtWidgets.QTableView):
def __init__(self):
super(EditTable, self).__init__()
self.setContextMenuPolicy(QtCore.Qt.CustomContextMenu)
self.customContextMenuRequested.connect(self.context_menu)
def context_menu(self):
context=QtWidgets.QMenu()
add_row=context.addAction("Add row")
add_row.triggered.connect(lambda: self.personnelTableModel.insertRows())
rem_row=context.addAction("Remove row")
rem_row.triggered.connect(lambda: self.personnelTableModel.removeRows())
cursor=QtGui.QCursor()
context.exec_(cursor.pos())
class MainWindow(QtWidgets.QMainWindow):
def __init__(self):
super(MainWindow, self).__init__()
widget = QtWidgets.QWidget()
layout = QtWidgets.QVBoxLayout()
widget.setLayout(layout)
button = QtWidgets.QPushButton("Push me")
self.db = maria_db.ConnectDb("localhost", "root", "1234", "test")
self.personnelTableModel = TableModel(self.db,"SELECT * FROM personnel","personnel","personnel_id")
table = EditTable()
table.setModel(self.personnelTableModel)
layout.addWidget(table)
layout.addWidget(button)
self.setCentralWidget(widget)
window = MainWindow()
window.show()
app.exec_()
So my problem is that when I call add_row.triggered.connect(lambda: self.personnelTableModel.insertRows()), I get a 'EditTable' object has no attribute 'personnelTableModel' which essentially means that there is no method insertRows in self. How can I refer to the model assigned to the object that is constructed using the subclass of the QTableView EditTable, through the subclass itself? Am I going about this the wrong way?

What is personnelTableModel for EditTable? the model, and how can I access the model from the view? Using the model() method. On the other hand, a lambda method is not necessary.
def context_menu(self):
context=QtWidgets.QMenu()
add_row=context.addAction("Add row")
add_row.triggered.connect(self.model().insertRows)
rem_row=context.addAction("Remove row")
rem_row.triggered.connect(self.model().removeRows)
cursor=QtGui.QCursor()
context.exec_(cursor.pos())

How to use QDataWidgetMapper in Qt or PyQt?

I can find some examples of how to use standard model with standard view.
http://doc.qt.io/qt-5/modelview.html
http://doc.qt.io/qt-5/qtwidgets-itemviews-simplewidgetmapper-example.html
but I just can not find ONE example of how to use QAbstractModel make my own model and to use it on my own view/widget.
After I update the model the stand view will update but not my own view.
Full code:
#!/usr/bin/env python
# -*- coding: utf-8 -*-
from PyQt5.QtWidgets import (QWidget, QLabel, QDataWidgetMapper,
QLineEdit, QApplication, QGridLayout)
from PyQt5.QtCore import QAbstractListModel, Qt
from PyQt5.QtWidgets import QListView
class Window(QWidget):
def __init__(self, model, parent=None):
super(Window, self).__init__(parent)
self.model = model
# Set up the widgets.
nameLabel = QLabel("Na&me:")
nameEdit = QLineEdit()
# Set up the mapper.
self.mapper = QDataWidgetMapper(self)
self.mapper.setModel(self.model)
self.mapper.addMapping(nameEdit, 0)
layout = QGridLayout()
layout.addWidget(nameLabel, 0, 0, 1, 1)
layout.addWidget(nameEdit, 0, 1, 1, 1)
self.setLayout(layout)
self.mapper.toFirst()
class MyModel(QAbstractListModel):
def __init__(self, status=[], parent=None):
super().__init__(parent)
self.status = status
def rowCount(self, index_parent=None, *args, **kwargs):
return len(self.status)
def data(self, index, role=Qt.DisplayRole, parent=None):
if not index.isValid():
return None
row = index.row()
if row == 0:
print(index)
if role == Qt.DisplayRole:
return self.status[row]
elif role == Qt.EditRole: # if it's editing mode, return value for editing
return self.status[row]
def flags(self, index):
return Qt.ItemIsEnabled | Qt.ItemIsEditable
def setData(self, index, value='', role=Qt.EditRole):
row = index.row()
if role == Qt.EditRole:
self.status[row] = value
self.dataChanged.emit(index, index) # inform the other view to request new data
return True
else:
return False
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
myModel_on_mywindow = MyModel([1, 2, 3])
mywindow = Window(myModel_on_mywindow)
mywindow.setWindowTitle('myModel_on_mywindow')
mywindow.show()
myModel_on_mywindow.status[0] = 2
myModel_on_qlistview = MyModel([1, 2, 3])
qlistview = QListView()
qlistview.show()
qlistview.setModel(myModel_on_qlistview)
qlistview.setWindowTitle('myModel_on_qlistview')
myModel_on_qlistview.status[0] = 2
sys.exit(app.exec_())

Your custom model needs to override some functions of the abstract model, depending on which one you subclass. This is a small example for subclassing the QAbstractListModel. You can read more about this in the Qt documentation: QAbstractListModel Details
class MyModel(QAbstractListModel):
def __init__(parent=None):
QAbstractListModel.__init__(parent)
self.content = [] # holds the data, you want to present
def rowCount(index):
return len(self.content)
# This defines what the view should present at given index
def data(index, role):
if index.isValid() and role == Qt.DisplayRole):
dataElement = self.content[index.row()]
if index.colum() == 0:
return dataElement.someBoolField
if index.colum() == 1:
return dataElement.someIntField
# ...
}
return QVariant() # this is like returning nothing
}
# If your items should be editable. Automatically called, when user changes the item.
def setData(index, value, role):
if index.isValid():
dataElement = self.content[index.row()].get()
if index.column() == 0:
return dataElement.tryToSetBoolField(value.toBool())
if index.column() == 1:
return dataElement.tryToSetIntField(value.toInt())
# ...
}
return True
}
};
# connecting your view with your model
model = MyModel()
myView = QTreeView() # or something else
myView.setModel(model)
EDIT
To update your view when using a custom Model in combination with a QDataMapper, call setCurrentIndex(changedIndex) or its wrappers after changing the model, like so in your case:
myModel_on_mywindow.status[0] = 2
myModel.mapper.toFirst()
The Qt documentation on QDataMapper mentions this in the detailed description:
The navigational functions toFirst(), toNext(), toPrevious(), toLast() and setCurrentIndex() can be used to navigate in the model and update the widgets with contents from the model.

Creating a model/view interface with sliders using PyQt

I have a GUI that consists of a number of sliders, and instead of updating the sliders manually when the underlying data changes, I'd like to store the data in a subclass of QAbstractListModel and have the slider positions update automatically. My subclass looks like this:
from PyQt4 import QtCore
class myDataModel(QtCore.QAbstractListModel):
def __init__(self, initData, parent=None):
super(myDataModel, self).__init__(parent)
self.__data = initData
def data(self, index, role=QtCore.Qt.DisplayRole):
if not index.isValid():
return None
if index.row() > len(self.__data):
return None
if role == QtCore.Qt.DisplayRole or role == QtCore.Qt.EditRole:
return self.__data[index.row()]
return None
def rowCount(self, parent=QtCore.QModelIndex()):
return len(self.__data)
def setData(self, index, value, role=QtCore.Qt.EditRole):
if not index.isValid() or role != QtCore.Qt.EditRole:
return False
self.__data[index.row()] = value
self.dataChanged.emit(index, index)
return True
How can I connect this model to the sliders in my GUI so that when the data in the model is changed, the sliders change, and vice versa?
Edit: Here is a mockup of the basic interface I have been working on:
Edit: I still haven't been able to get this to work. Here is my model class:
class dataModel(QtCore.QAbstractListModel):
def __init__(self, initData, parent=None):
super(dataModel, self).__init__(parent)
self.__data = initData
def data(self, index, role=QtCore.Qt.DisplayRole):
if not index.isValid():
return None
if index.row() > len(self.__data):
return None
if role == QtCore.Qt.DisplayRole or role == QtCore.Qt.EditRole:
return self.__data[index.row()]
return None
def rowCount(self, parent=QtCore.QModelIndex()):
return len(self.__data)
def setData(self, index, value, role=QtCore.Qt.EditRole):
if not index.isValid() or role != QtCore.Qt.EditRole:
return False
self.__data[index.row()] = value
self.dataChanged.emit(index, index)
return True
Here is the Delegate class:
class sliderDelegate(QtGui.QItemDelegate):
'''
classdocs
'''
def __init__(self, parent=None):
'''
Constructor
'''
super(sliderDelegate, self).__init__(parent)
def setEditorData(self, editor, index):
editor.setValue(index.model().data(index, QtCore.Qt.EditRole))
def setModelData(self, editor, model, index):
model.setData(index, editor.value(), QtCore.Qt.EditRole)
And here is the setup code:
self._model = dataModel([0 for i in xrange(20)])
self._parameterMapper = QtGui.QDataWidgetMapper(mainWindowInstance)
self._parameterMapper.setModel(self._model)
self._parameterMapper.setItemDelegate(sliderDelegate(mainWindowInstance))
self._parameterMapper.addMapping(self._mainWindowInstance.ui.mySlider, 0)
self._parameterMapper.toFirst()
Unfortunately I get the following error when toFirst() is called:
editor.setValue(index.model().data(index, QtCore.Qt.EditRole))
AttributeError: 'NoneType' object has no attribute 'data'
Any help would be appreciated.

So I haven't used QDataWidgetMapper. It does look interesting, but looks more useful for when you want to have multiple widgets updated to a particular row in a model (and be able to switch between rows easily), rather than each row of a model corresponding to the value of a widget (which I think is what you are after).
So this is my rather rough implementation. Hopefully you'll be able to extend it to your application (might need a bit more error checking added, and maybe the ability to link multiple sliders to a single model row, and possibly then extending to other types of widgets)
When you drag the slider, the model is updated to the sliders new value. I've also added a text box where you can type in a number, and click the button, which will set the model to a specific value. You will notice the slider will update to this value!
import sys
from PyQt4 import QtGui
from PyQt4 import QtCore
class MainWindow(QtGui.QWidget):
def __init__(self):
super(MainWindow, self).__init__()
main_layout = QtGui.QVBoxLayout()
# Create the model
self.model = MyModel()
# Create a slider and link it to the model
self.slider1 = QtGui.QSlider()
self.model.add_slider(self.slider1)
main_layout.addWidget(self.slider1)
# Add a lineEdit and button to force update the model
# Note that the LineEdit is not linked to the model, so won't update with the slider
self.edit = QtGui.QLineEdit()
button = QtGui.QPushButton('update model')
button.clicked.connect(self.on_clicked)
main_layout.addWidget(self.edit)
main_layout.addWidget(button)
self.setLayout(main_layout)
def on_clicked(self):
self.model.update_model(int(self.edit.text()),self.slider1)
class MyModel(QtGui.QStandardItemModel):
def __init__(self,*args,**kwargs):
super(MyModel,self).__init__(*args,**kwargs)
self._slider_list = {}
self.itemChanged.connect(self.on_item_changed)
def add_slider(self,slider):
if slider in self._slider_list:
raise Exception('You cannot link a slider to the model twice')
item = QtGui.QStandardItem(str(slider.value()))
self._slider_list[slider] = item
self.appendRow(item)
slider.valueChanged.connect(lambda value: self.update_model(value,slider))
def update_model(self,value,slider):
if str(value) != self._slider_list[slider].text():
self._slider_list[slider].setText(str(value))
print 'update_model: %d'%value
def on_item_changed(self,item):
slider = self._slider_list.keys()[self._slider_list.values().index(item)]
if slider.value() != int(item.text()):
slider.setValue(int(item.text()))
print 'on_item_changed: %s'%item.text()
app = QtGui.QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
Hope that helps!