Develop Reference

How to have multiple columns in a QComboBox with a QAbstractTableModel

I've seen questions similar to this one but they are aimed at QTableView. This is not using that,, this is just for a dropdown (QComboBox) with a custom QAbstractTableModel, which needs to have 2 columns.
BIG UPDATE
(Note: Legacy code has been deleted as this is a better approach on the same question, and legacy code was confusing as hell).
Okay, so trying to catch up with what #eyllanesc explained, I changed this from a QAbstractListModel to a QAbstractTableModel. The result is:
class ModelForComboboxesWithID(QAbstractTableModel):
"""Create our basic model"""
def __init__(self, program, records):
super(ModelForComboboxesWithID, self).__init__()
self._data = records
self.program = program
self.path_images = program.PATH_IMAGES
def rowCount(self, index: int = 0) -> int:
"""The length of the outer list. Structure: [row, row, row]"""
if not self._data:
return 0 # Doubt: Do we need to return this if self._data is empty?
return len(self._data)
def columnCount(self, index: int = 0) -> int:
"""The length of the sub-list inside the outer list. Meaning that Columns are inside rows
Structure: [row [column], row [column], row [column]]"""
if not self._data:
return 0 # Doubt: Do we need to return this if self._data is empty?
return len(self._data[0])
def data(self, index, role=None):
"""return the data on this index as data[row][column]"""
# 1 - Display data based on its content (this edits the text that you visually see)
if role == Qt.DisplayRole:
value = self._data[index.row()][index.column()]
return value
# 2 - Tooltip displayed when hovering on it
elif role == Qt.ToolTipRole:
return f"ID: {self._data[index.row()][1]}"
Which I set this way:
def eventFilter(self, target, event: QEvent):
if event.type() == QEvent.MouseButtonPress:
if target == self.Buscadorcombo_cliente:
records = ... # my query to the database
set_combo_records_with_ids(self.program, target, records)
target.currentIndexChanged.connect(self.test)
def set_combo_records_with_ids(program, combobox: QComboBox, records):
"""Clear combobox, set model/data and sort it"""
combobox.clear()
model = ModelForComboboxesWithID(program, records)
combobox.setModel(model)
combobox.model().sort(0, Qt.AscendingOrder)
combobox.setModelColumn(0)
The result of this works almost perfect:
On the dropdown(Combobox) it displays the name.
If you hover on an item, it displays the ID.
Now I am able to get any data of it this way.
def test(self, index):
data_id = self.Buscadorcombo_cliente.model().index(index, 1).data()
data_name = self.Buscadorcombo_cliente.model().index(index, 0).data()
print(data_id)
print(data_name)

You have to set a QTableView as a view:
from PySide2 import QtGui, QtWidgets
def main():
import sys
app = QtWidgets.QApplication(sys.argv)
w = QtWidgets.QWidget()
combo = QtWidgets.QComboBox()
model = QtGui.QStandardItemModel(0, 2)
for i in range(10):
items = []
for j in range(model.columnCount()):
it = QtGui.QStandardItem(f"it-{i}{j}")
items.append(it)
model.appendRow(items)
combo.setModel(model)
view = QtWidgets.QTableView(
combo, selectionBehavior=QtWidgets.QAbstractItemView.SelectRows
)
combo.setView(view)
view.verticalHeader().hide()
view.horizontalHeader().hide()
header = view.horizontalHeader()
for i in range(header.count()):
header.setSectionResizeMode(i, QtWidgets.QHeaderView.Stretch)
lay = QtWidgets.QVBoxLayout(w)
lay.addWidget(combo)
lay.addStretch()
w.resize(640, 480)
w.show()
sys.exit(app.exec_())
if __name__ == "__main__":
main()

pyqt adding column at a tableview using QThread

I have some problem adding rows at a qtableview using thread for preventing GUI blocking. The number of rows is quite large. (may be 1800 ~ 3000 and each row has graph consisting of large data plot.) So it is simply predicted that Main GUI Thread is block by adding large number of rows if I don't use QThread. Yeah, it is fine so far.
So I implements above to solve the problem that I mentioned, but the problem still remains.
class ColumnTableView(MyTableView):
HistogramColumnNum = 3
def __init__(self. *args, **kwargs)
MyTableView.__init__(*args, **kwargs)
def beginInsertMode(self, mIdx, sIdx, eIdx):
self.model().beginResetModel()
def endInsertMode(self):
self.model().endResetModel()
def setData(self, data, ):
if data is None:
return
data = data['outputs']
keys = list(data.keys())
try:
data = data[keys[0]]
except:
return
self.wholeData = data
model = self.model()
model.items = []
self.reset()
if data is not None:
dqData = data
model.beginResetModel()
model.endResetModel()
self.worker.requestBeginInsertMode.connect(self.beginInsertMode)
self.worker.requestEndInsertMode.connect(self.endInsertMode)
self.worker.setData(data, model)
self.worker.start()
class Worker(QThread):
requestBeginInsertMode = pyqtSignal()
requestEndInsertMode = pyqtSignal()
def __init__(self, parent=None):
QThread.__init__(self, parent)
self.data = None
self.model = None
def setData(self, data, model):
self.model = model
self.data = data
def run(self):
data = self.data.npData
model = self.model
cols = data.shape[1]
for idx in range(cols):
print(idx)
col = data[:, idx]
item = Column(str(self.data.header[idx]), str(col.dtype), str(countOmissionData(col)), col)
model.addColumn(item)
self.requestEndInsertMode.emit()
class ColumnModel(QAbstractTableModel):
def __init__(self):
super(ColumnModel, self).__init__()
def rowCount(self, index=QModelIndex()):
if not self.items:
return 0
else:
return len(self.items)
def addColumn(self, column):
self.items.append(column)
So I implements multithread that actually add rows(named Column in my code. Sorry for confusing.) but it is not work (adding column still block the main GUI thread.)
How can I solve this problem?

PyQt5 - Unexpected behaviour of QTreeView when a QSortFilterProxyModel is set as model

I am developing an application with PyQt5 5.7.1 on Python 3.5. I use a QTreeView to display some data with a hierachy. I would like to be able to filter this data, so I used a QSortFilterProxy model.
self.model = CustomTreeModel(data)
self.proxy = QSortFilterProxyModel(self.model)
self.ui.treeView.setModel(self.proxy)
This gives a strange behaviour:
By default, the treeView is collapsed. If I expand any item which is not the first one, and then click on any of its children, the first item of the treeView gets expanded (it shouldn't). Actually, whenever I click on any item which is not first level (a child of the root item), the first child of the root item gets expanded.
I thought there was an issue with my model, but if I don't use QSortFilterProxy model, like this :
self.model = CustomTreeModel(data)
self.ui.treeView.setModel(self.model)
The treeView behaves as expected, the first element doesn't expand when it shouldn't.
It seems to me that this is a bug in PyQt5, but I didn't find any information about it on the Internet. On the contrary, there are some examples of using QSortFilterProxyModel with a QTreeView and nobody seems to report such issue. So is it really a bug in PyQt or am I missing something ?
Here is a demo code:
from PyQt5.QtCore import QAbstractItemModel, QModelIndex, Qt
class CustomTreeModel(QAbstractItemModel):
# Based on http://trevorius.com/scrapbook/uncategorized/pyqt-custom-abstractitemmodel/
def __init__(self, headerData, nodes):
QAbstractItemModel.__init__(self)
self._headerData = headerData
self._root = CustomNode(None)
for node in nodes:
self._root.addChild(node)
def addChild(self, in_node, in_parent=QModelIndex()):
if not in_parent or not in_parent.isValid():
parent = self._root
else:
parent = in_parent.internalPointer()
parent.addChild(in_node)
def index(self, in_row, in_column, in_parent=QModelIndex()):
if not in_parent.isValid():
parent = self._root
else:
parent = in_parent.internalPointer()
if not QAbstractItemModel.hasIndex(self, in_row, in_column, in_parent):
return QModelIndex()
child = parent.child(in_row)
if child:
return QAbstractItemModel.createIndex(self, in_row, in_column, child)
else:
return QModelIndex()
def rowCount(self, in_index=QModelIndex()):
if in_index.isValid():
return in_index.internalPointer().childCount()
return self._root.childCount()
def child(self, row, index):
if index.isValid():
c = index.internalPointer().child(row)
return QAbstractItemModel.createIndex(self, row, 0, c)
return QModelIndex()
def parent(self, in_index):
if in_index.isValid():
p = in_index.internalPointer().parent()
if p:
return QAbstractItemModel.createIndex(self, p.row(),0,p)
return QModelIndex()
def columnCount(self, in_index):
if in_index.isValid():
return in_index.internalPointer().columnCount()
return self._root.columnCount()
def data(self, in_index, role):
if not in_index.isValid():
return None
node = in_index.internalPointer()
if role == Qt.DisplayRole:
return node.data(in_index.column())
return None
def headerData(self, section, orientation, role=Qt.DisplayRole):
if (section < 0) or (section > self.columnCount(QModelIndex())):
return None
if (orientation == Qt.Horizontal) and (role == Qt.DisplayRole):
return self._headerData[section]
return None
class CustomNode(object):
def __init__(self, in_data):
self._data = in_data
if type(in_data) == tuple:
self._data = list(in_data)
if type(in_data) == str or not hasattr(in_data, '__getitem__'):
self._data = [in_data]
self._columncount = len(self._data)
self._children = []
self._parent = None
self._row = 0
def data(self, in_column):
if in_column >= 0 and in_column < len(self._data):
return self._data[in_column]
return None
def columnCount(self):
return self._columncount
def childCount(self):
return len(self._children)
def child(self, in_row):
if in_row >= 0 and in_row < self.childCount():
return self._children[in_row]
return None
def parent(self):
return self._parent
def row(self):
return self._row
def addChild(self, in_child):
in_child._parent = self
in_child._row = len(self._children)
self._children.append(in_child)
self._columncount = max(in_child.columnCount(), self._columncount)
if __name__ == '__main__':
import sys
from PyQt5.QtCore import QSortFilterProxyModel
from PyQt5.QtWidgets import QApplication, QTreeView
app = QApplication(sys.argv)
header = ['Food']
fruits = CustomNode(['Fruit'])
fruits.addChild(CustomNode(['Apple']))
fruits.addChild(CustomNode(['Banana']))
fruits.addChild(CustomNode(['Orange']))
vegetables = CustomNode(['Vegetables'])
vegetables.addChild(CustomNode(['Carott']))
vegetables.addChild(CustomNode(['Potato']))
meat = CustomNode(['Meat'])
meat.addChild(CustomNode(['Beef']))
meat.addChild(CustomNode(['Chicken']))
meat.addChild(CustomNode(['Pork']))
nodes = [fruits, vegetables, meat]
v = QTreeView()
model = CustomTreeModel(header, nodes)
proxy = QSortFilterProxyModel()
proxy.setSourceModel(model)
v.setModel(proxy)
v.show()
sys.exit(app.exec_())

How to lazy load changing data into a QColumnView (with PyQt)?

I have a hierarchical data source for a QColumnView I want to fill. The data source loads the data from a server using a REST interface.
Lets say the hierarchy looks like this:
Car_Manufacturer -> Car_Type -> Specific_Model -> Motor_Type
I have to use a QColumnView to display this (since it is a customer requirement). The behavior is supposed to be like this:
When the program starts, it loads the Car_Manufacturer from the server. When one of the Car_Manufacturer items is clicked, the Car_Type items for the selected Car_Manufacturer is loaded from the server and displayed in a new column. When the Car_Manufacturer is clicked again, the data has to be fetched again from the server and the column has to be updated. When Car_Type is clicked, the Specific_Model items for this Car_Manufacturer and Car_type have to be queried from the server and loaded into a new column... and so on.
The datasource has this api:
datasource.get_manufacturers(hierarchy) # hierarchy = []
datasource.get_car_type(hierarchy) # hierarchy = [manufacturer, ]
datasource.get_specific_model(hierarchy) # hierarchy = [manufacturer, car_type]
datasource.get_motor_type(hierarchy) # hierarchy = [manufacturer, car_type, specific_model ]
Where each element in the hierarchy is a string key representation of the item. When an item is clicked it has to inform a controller about this with the hierarchy of the curernt item.
How can I get the QColumnView to update the children of one item when the item is clicked using the datasource? How can this stay flexible when a new hierarchy layer is added or removed?

Here is an example which implements a custom DirModel.
The method _create_children is called lazily and should return a list of instances which implement AbstractTreeItem.
import sys
import os
import abc
from PyQt4.QtCore import QAbstractItemModel, QModelIndex, Qt, QVariant
from PyQt4.QtGui import QColumnView, QApplication
class TreeModel(QAbstractItemModel):
def __init__(self, root, parent=None):
super(TreeModel, self).__init__(parent)
self._root_item = root
self._header = self._root_item.header()
def columnCount(self, parent=None):
if parent and parent.isValid():
return parent.internalPointer().column_count()
else:
return len(self._header)
def data(self, index, role):
if not index.isValid():
return QVariant()
item = index.internalPointer()
if role == Qt.DisplayRole:
return item.data(index.column())
if role == Qt.UserRole:
if item:
return item.person
return QVariant()
def headerData(self, column, orientation, role):
if orientation == Qt.Horizontal and role == Qt.DisplayRole:
try:
return QVariant(self._header[column])
except IndexError:
pass
return QVariant()
def index(self, row, column, parent):
if not self.hasIndex(row, column, parent):
return QModelIndex()
if not parent.isValid():
parent_item = self._root_item
else:
parent_item = parent.internalPointer()
child_item = parent_item.child_at(row)
if child_item:
return self.createIndex(row, column, child_item)
else:
return QModelIndex()
def parent(self, index):
if not index.isValid():
return QModelIndex()
child_item = index.internalPointer()
if not child_item:
return QModelIndex()
parent_item = child_item.parent()
if parent_item == self._root_item:
return QModelIndex()
return self.createIndex(parent_item.row(), 0, parent_item)
def rowCount(self, parent=QModelIndex()):
if parent.column() > 0:
return 0
if not parent.isValid():
parent_item = self._root_item
else:
parent_item = parent.internalPointer()
return parent_item.child_count()
class AbstractTreeItem(object):
__metaclass__ = abc.ABCMeta
def __init__(self, parent=None):
self._children = None
self._parent = parent
#abc.abstractmethod
def header(self):
#return ["name"]
raise NotImplementedError(self.header)
#abc.abstractmethod
def column_count(self):
#return 1
raise NotImplementedError(self.column_count)
def parent(self):
return self._parent
#abc.abstractmethod
def _create_children(self):
# subclass this method
return []
def row(self):
if self._parent:
return self._parent._children.index(self)
return 0
#property
def children(self):
if self._children is None:
self._children = self._create_children()
return self._children
def child_at(self, row):
return self.children[row]
#abc.abstractmethod
def data(self, column):
#return ""
raise NotImplementedError(self.data)
def child_count(self):
count = len(self.children)
return count
class DirPathModel(AbstractTreeItem):
def __init__(self, root="/", parent=None):
super(DirPathModel, self).__init__(parent)
self._root = root
def _create_children(self):
print "walking into", self._root
children = []
try:
entries = os.listdir(self._root)
except OSError:
# no permission etc
entries = []
for name in entries:
fn = os.path.join(self._root, name)
if os.path.isdir(fn):
children.append(self.__class__(fn, self))
return children
def data(self, column):
#assert column == 0
return os.path.basename(self._root)
def header(self):
return ["name"]
def column_count(self):
return 1
def main():
app = QApplication(sys.argv)
view = QColumnView()
view.setWindowTitle("Dynamic Column view test")
view.resize(1024, 768)
root = DirPathModel("/")
model = TreeModel(root)
view.setModel(model)
view.show()
return app.exec_()
if __name__ == "__main__":
sys.exit(main() or 0)

Asuming you can't bring all data at once and filter it out, you'll have to modify the item model (adding and removing rows) on the go based on whatever the user has selected from the QColumnView.
There's more than one way to remove the items:
You can use the index of the selected column and remove all items "on the left" of this column.
You can remove items based whose parent (or grandparent) matches the selection being made
Any option you take, you'll have to mirror the relationship between items in some way. That or implement from QAbstractItemModel, which I think would be an overkill.

PyQt4 : Drag and Drop in QTreeView

I make a UI with PyQt4. It has a treeView and I want to deal with it.
The treeView is made up with model-base. I create a data in .py file and import it.
So, I can see the data tree in my treeView.
But I can't drag and drop it, so can't change the order.
I referred some articles so add it in my script, but they couldn't work.
I plant some "print", so I chased my problem.
I found that when drag a item, it transferred to MIME data.
But when it is dropped, I can't find any outputs.
It seems that the script doesn't call "dropMimeData" method.
How can I fix my script?
from PyQt4 import QtCore, QtGui
from setting import *
from copy import deepcopy
from cPickle import dumps, load, loads
from cStringIO import StringIO
class PyMimeData(QtCore.QMimeData):
MIME_TYPE = QtCore.QString('text/plain')
def __init__(self, data=None):
QtCore.QMimeData.__init__(self)
self._local_instance = data
if data is not None:
try:
pdata = dumps(data)
except:
return
self.setData(self.MIME_TYPE, dumps(data.__class__) + pdata)
#classmethod
def coerce(cls, md):
if isinstance(md, cls):
return md
if not md.hasFormat(cls.MIME_TYPE):
return None
nmd = cls()
nmd.setData(cls.MIME_TYPE, md.data())
return nmd
def instance(self):
if self._local_instance is not None:
return self._local_instance
io = StringIO(str(self.data(self.MIME_TYPE)))
try:
load(io)
return load(io)
except:
pass
return None
def instanceType(self):
if self._local_instance is not None:
return self._local_instance.__class__
try:
return loads(str(self.data(self.MIME_TYPE)))
except:
pass
return None
class treeItem(QtGui.QStandardItem):
def __init__(self, data, parent=None):
super(treeItem, self).__init__(data)
self.parentItem = parent
self.itemData = data
self.childItems = []
def appendChild(self, item):
self.childItems.append(item)
def parent(self):
return self.parentItem
def childAtRow(self, row):
return self.childItems[row]
def rowOfChild(self, child):
for i, item in enumerate(self.childItems):
if item == child:
return i
return -1
class treeModel(QtGui.QStandardItemModel):
def __init__(self, name, parent=None):
super(treeModel, self).__init__(parent)
self.headerName = name
self.childItems = []
def appendChild(self, item):
self.childItems.append(item)
def removeRowAll(self):
pass
def addItemList(self, parent, elements):
for text, children in elements:
item = treeItem(text, parent)
self.addItems(parent, item)
if children:
self.addItemList(item, children)
def addItems(self, parent, inputItem):
parent.appendRow(inputItem)
parent.appendChild(inputItem)
def headerData(self, section, orientation, role):
if orientation == QtCore.Qt.Horizontal and role == QtCore.Qt.DisplayRole:
return self.headerName
def supportedDropActions(self):
return QtCore.Qt.MoveAction | QtCore.Qt.CopyAction
def flags(self, index):
defaultFlags = QtCore.QAbstractItemModel.flags(self, index)
if index.isValid():
return QtCore.Qt.ItemIsEditable | QtCore.Qt.ItemIsDragEnabled | QtCore.Qt.ItemIsDropEnabled | defaultFlags
else:
return QtCore.Qt.ItemIsDropEnabled | defaultFlags
def mimeTypes(self):
types = QtCore.QStringList()
types.append('text/plain')
return types
def mimeData(self, index):
node = self.nodeFromIndex(index[0])
mimeData = PyMimeData(node)
return mimeData
def dropMimeData(self, mimedata, action, row, column, parentIndex):
print mimedata, action, row, column, parentIndex
if action == QtCore.Qt.IgnoreAction:
return True
dragNode = mimedata.instance()
print dragNode
parentNode = self.nodeFromIndex(parentIndex)
# copy of node being moved
newNode = deepcopy(dragNode)
print newNode
newNode.setParent(parentNode)
self.insertRow(len(parentNode)-1, parentIndex)
self.emit(QtCore.SIGNAL("dataChanged(QtCore.QModelIndex,QtCore.QModelIndex)"), parentIndex, parentIndex)
return True
def nodeFromIndex(self, index):
##return index.internalPointer() if index.isValid() else self.root
return index.model() if index.isValid() else self.parent()
def insertRow(self, row, parent):
return self.insertRows(row, 1, parent)
def insertRows(self, row, count, parent):
self.beginInsertRows(parent, row, (row + (count - 1)))
self.endInsertRows()
return True
def removeRow(self, row, parentIndex):
return self.removeRows(row, 1, parentIndex)
def removeRows(self, row, count, parentIndex):
self.beginRemoveRows(parentIndex, row, row)
node = self.nodeFromIndex(parentIndex)
node.removeChild(row)
self.endRemoveRows()
return True
added script
here is ui creation (the script above is imported in this script)
class RigControlWindow(QtGui.QMainWindow, Ui_MainWindow):
def __init__(self, parent = getMayaWindow()):
super(RigControlWindow, self).__init__(parent)
self.setupUi(self)
self.bodyrig_treelist.setDragEnabled(1)
self.bodyrig_treelist.setAcceptDrops(1)
self.bodyrig_treelist.setDropIndicatorShown(1)
self.bodyrig_treelist.setDragDropMode(QtGui.QAbstractItemView.InternalMove)
QtCore.QObject.connect(self.finalize_button, QtCore.SIGNAL("clicked()"), self.AddData_treeList)
def AddData_treeList(self):
self.localtreeModel = treeModel("objects")
self.bodyrig_treelist.setModel(self.localtreeModel)
self.localtreeModel.addItemList(self.localtreeModel, data)
and data is
data = [("root",[("upper",[("hand",[]),
("head",[])
]),
("lower",[("leg",[]),
("foot",[])
])
])
]

The QTreeView.dragMoveEvent and QTreeView.dragEnterEvent methods both check the object returned by event.mimeData() to see if it can return data for any of the formats supported by the model (i.e. those returned by model.mimeTypes()).
But your PyMimeData subclass doesn't support any formats, because it never successfully sets the data passed to its constructor.
The problem is located in PyMimeData.__init__:
...
try:
pdata = dumps(data)
except:
return
self.setData(self.MIME_TYPE, dumps(data.__class__) + pdata)
The data is passed in from the treeModel.mimeData method:
def mimeData(self, index):
node = self.nodeFromIndex(index[0])
mimeData = PyMimeData(node)
return mimeData
But if you check the type of data/node you'll see that it is a treeModel instance, and so dumps(data) will fail because data can't be pickled. As a result of this, the PyMimeData object is not initialized properly, and so it is ignored by drag events.