I want to have a QListView which displays custom widgets. I guess the best way to do this would be a QItemDelegate. Unfortunately I don't quite understand how to subclass it correctly and how to implement the paint() method, which seems to be the most important one. I couldn't find anything about using a delegate to create another widget.
I already tried to implement something similar without a delegate, but that didn't work out that well, because QListView is not supposed to display widgets.
import sys
from PyQt4 import QtCore
from PyQt4 import QtGui
class Model(QtCore.QAbstractListModel):
def __init__(self, parent=None):
super(QtCore.QAbstractListModel, self).__init__(parent)
self._widgets = []
def headerData(self, section, orientation, role):
""" Returns header for columns """
return "Header"
def rowCount(self, parentIndex=QtCore.QModelIndex()):
""" Returns number of interfaces """
return len(self._widgets)
def data(self, index, role):
""" Returns the data to be displayed """
if role == QtCore.Qt.DisplayRole:
row = index.row()
return self._widgets[row]
def insertRow(self, widget, parentIndex=QtCore.QModelIndex()):
""" Inserts a row into the model """
self.beginInsertRows(parentIndex, 0, 1)
self._widgets.append(widget)
self.endInsertRows()
class Widget(QtGui.QWidget):
def __init__(self, parent=None, name="None"):
super(QtGui.QWidget, self).__init__(parent)
self.layout = QtGui.QHBoxLayout()
self.setLayout(self.layout)
self.checkbox = QtGui.QCheckBox()
self.button = QtGui.QPushButton(self)
self.label = QtGui.QLabel(self)
self.label.setText(name)
self.layout.addWidget(self.checkbox)
self.layout.addWidget(self.button)
self.layout.addWidget(self.label)
class Window(QtGui.QMainWindow):
def __init__(self, parent=None):
super(QtGui.QMainWindow, self).__init__(parent)
self.view = QtGui.QListView(self)
self.model = Model()
self.view.setModel(self.model)
self.setCentralWidget(self.view)
self.model.insertRow(
widget=Widget(self)
)
self.model.insertRow(
widget=Widget(self)
)
self.model.insertRow(
widget=Widget(self)
)
self.model.insertRow(
widget=Widget(self)
)
self.show()
app = QtGui.QApplication(sys.argv)
window = Window()
sys.exit(app.exec_())
So, how would I need to implement a delegate in order to do what I want?
Here's an example of a QTableWidget with a button and text on each row. I defined an add_item method to add a whole row at once: insert a new row, put a button in column 0, put a regular item in column 1.
import sys
from PyQt4 import QtGui,QtCore
class myTable(QtGui.QTableWidget):
def __init__(self,parent=None):
super(myTable,self).__init__(parent)
self.setColumnCount(2)
def add_item(self,name):
#new row
row=self.rowCount()
self.insertRow(row)
#button in column 0
button=QtGui.QPushButton(name)
button.setProperty("name",name)
button.clicked.connect(self.on_click)
self.setCellWidget(row,0,button)
#text in column 1
self.setItem(row,1,QtGui.QTableWidgetItem(name))
def on_click(self):
# find the item with the same name to get the row
text=self.sender().property("name")
item=self.findItems(text,QtCore.Qt.MatchExactly)[0]
print("Button click at row:",item.row())
if __name__=='__main__':
app = QtGui.QApplication(sys.argv)
widget = myTable()
widget.add_item("kitten")
widget.add_item("unicorn")
widget.show()
sys.exit(app.exec_())
Bonus: how to know on which button did the user clicked ? A button doesn't have a row property, but we can create one when we instantiate the buttons, like so:
button.setProperty("row",row)
Problem is, if you sort your table or delete a row, the row numbers will not match any more. So instead we set a "name" property, same as the text of the item in column 1. Then we can use findItems to get the row (see on_click).
Related
I am making a QtreeWidget with item editable,but the problem is with the Item Editor or QAbstractItemDelegate(might be called like this,not sure).I am unable to change the stylesheet,actually i dont know how to do this.And also i want the selected lines(blue in editor) should be according to my wish.like below picture
here i want that blue selected line upto ".jpg",so that anyone cant change that ".jpg". Only ,one can change upto this".jpg"
Here is my code:
import sys
from PyQt5 import QtCore, QtWidgets
class Window(QtWidgets.QWidget):
def __init__(self):
super().__init__()
self.button = QtWidgets.QPushButton('Edit')
self.button.clicked.connect(self.edittreeitem)
self.tree = QtWidgets.QTreeWidget()
self.tree.setStyleSheet('background:#333333;color:grey')
layout = QtWidgets.QVBoxLayout(self)
layout.addWidget(self.tree)
layout.addWidget(self.button)
columns = 'ABCDE'
self.tree.setColumnCount(len(columns))
for index in range(50):
item=QtWidgets.QTreeWidgetItem(
self.tree, [f'{char}{index:02}.jpg' for char in columns])
item.setFlags(item.flags()|QtCore.Qt.ItemIsEditable)
def edittreeitem(self):
getSelected = self.tree.selectedItems()
self.tree.editItem(getSelected[0],0)
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
window = Window()
window.setWindowTitle('Test')
window.setGeometry(800, 100, 540, 300)
window.show()
sys.exit(app.exec_())
You can create your own delegate that only considers the base name without the extension, and then set the data using the existing extension.
class BaseNameDelegate(QtWidgets.QStyledItemDelegate):
def setEditorData(self, editor, index):
editor.setText(QtCore.QFileInfo(index.data()).completeBaseName())
def setModelData(self, editor, model, index):
name = editor.text()
if not name:
return
suffix = QtCore.QFileInfo(index.data()).suffix()
model.setData(index, '{}.{}'.format(name, suffix))
class Window(QtWidgets.QWidget):
def __init__(self):
# ...
self.tree.setItemDelegate(BaseNameDelegate(self.tree))
The only drawback of this is that the extension is not visible during editing, but that would require an implementation that is a bit more complex than that, as QLineEdit (the default editor for string values of a delegate) doesn't provide such behavior.
I have a Qgroupbox which contains Qcombobox with Qlabels, I want to select a value from Qcombobox and display the value as Qlabel. I have the complete code, even I do print value before and after within function every thing works as it should, Only display setText wont set text to Qlabel and update it.
Current screen
What I want
I've corrected signal code, when Qgroupbox in it Qcombobox appears or value would be changed, self.activation.connect(......) would emit an int of the index. to ensure that would work I print it-value inside the def setdatastrength(self, index), see figure below indeed it works, then argument would be passed to function self.concreteproperty.display_condata(it) would be called and do a print of value inside def display_condata(self, value) to make sure about value passing, as shown figure below, it does work. This line code self.con_strength_value.setText(fmt.format(L_Display))
wont assign value to Qlabel.
The script
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
class secondtabmaterial(QtWidgets.QWidget):
def __init__(self, parent=None):
super(secondtabmaterial, self).__init__(parent)
self.concretewidgetinfo = ConcreteStrengthInFo()
Concrete_Group = QtWidgets.QGroupBox(self)
Concrete_Group.setTitle("&Concrete")
Concrete_Group.setLayout(self.concretewidgetinfo.grid)
class ConcreteStrengthComboBox(QtWidgets.QComboBox):
def __init__(self, parent = None):
super(ConcreteStrengthComboBox, self).__init__(parent)
self.addItems(["C12/15","C16/20","C20/25","C25/30","C30/37","C35/45"
,"C40/50","C45/55","C50/60","C55/67","C60/75","C70/85",
"C80/95","C90/105"])
self.setFont(QtGui.QFont("Helvetica", 10, QtGui.QFont.Normal, italic=False))
self.compressive_strength = ["12","16","20","25","30","35","40",
"45","50","55","60","70","80","90"]
class ConcreteProperty(QtWidgets.QWidget):
def __init__(self, parent=None):
super(ConcreteProperty, self).__init__(parent)
self.setFont(QtGui.QFont("Helvetica", 10, QtGui.QFont.Normal, italic=False))
concretestrength_lay = QtWidgets.QHBoxLayout(self)
fctd = "\nfcd\n\nfctd\n\nEc"
con_strength = QtWidgets.QLabel(fctd)
self.con_strength_value = QtWidgets.QLabel(" ")
concretestrength_lay.addWidget(con_strength)
concretestrength_lay.addWidget(self.con_strength_value, alignment=QtCore.Qt.AlignRight)
self.setLayout(concretestrength_lay)
#QtCore.pyqtSlot(int)
def display_condata(self, value):
try:
L_Display = str(value)
print("-------- After ------")
print(L_Display, type(L_Display))
fmt = "{}mm"
self.con_strength_value.setText(fmt.format(L_Display))
except ValueError:
print("Error")
class ConcreteStrengthInFo(QtWidgets.QWidget):
def __init__(self, parent=None):
super(ConcreteStrengthInFo, self).__init__(parent)
self.concreteproperty = ConcreteProperty()
self.concretestrengthbox = ConcreteStrengthComboBox()
self.concretestrengthbox.activated.connect(self.setdatastrength)
hbox = QtWidgets.QHBoxLayout()
concrete_strength = QtWidgets.QLabel("Concrete strength: ")
hbox.addWidget(concrete_strength)
hbox.addWidget(self.concretestrengthbox)
self.grid = QtWidgets.QGridLayout()
self.grid.addLayout(hbox, 0, 0)
self.grid.addWidget(self.concreteproperty, 1, 0)
#QtCore.pyqtSlot(int)
def setdatastrength(self, index):
it = self.concretestrengthbox.compressive_strength[index]
self.concreteproperty.display_condata(it)
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
w = secondtabmaterial()
w.show()
sys.exit(app.exec_())
Above code is corrected and final. Now it works as it should.
I think the issue is that your receiving slot doesn't match any of the available .activated signals.
self.activated.connect(self.setdatastrength)
#QtCore.pyqtSlot()
def setdatastrength(self):
index = self.currentIndex()
it = self.compressive_strength[index]
print(it)
self.concreteproperty.display_condata(it)
The QComboBox.activated signal emits either an int of the index, or a str of the selected value. See documentation.
You've attached it to setdatastrength which accepts doesn't accept any parameters (aside from self, from the object) — this means it doesn't match the signature of either available signal, and won't be called. If you update the definition to add the index value, and accept a single int it should work.
self.activated.connect(self.setdatastrength)
#QtCore.pyqtSlot(int) # add the target type for this slot.
def setdatastrength(self, index):
it = self.compressive_strength[index]
print(it)
self.concreteproperty.display_condata(it)
After the update — the above looks now to be fixed, although you don't need the additional index = self.currentIndex() in setdatastrength it's not doing any harm.
Looking at your code, I think the label is being updated. The issue actually is that you can't see the label at all. Looking at the init for ConcreteProperty
class ConcreteProperty(QtWidgets.QWidget):
def __init__(self, parent=None):
super(ConcreteProperty, self).__init__(parent)
self.setFont(QtGui.QFont("Helvetica", 10, QtGui.QFont.Normal, italic=False))
self.concretestrength_lay = QtWidgets.QHBoxLayout()
fctd = "\nfcd\n\nfctd\n\nEc"
con_strength = QtWidgets.QLabel(fctd)
self.con_strength_value = QtWidgets.QLabel(" ")
self.concretestrength_lay.addWidget(con_strength)
self.concretestrength_lay.addWidget(self.con_strength_value, alignment=QtCore.Qt.AlignLeft)
The reason the changes are not appearing is that you create two ConcreteProperty objects, one in ConcreteStrengthInfo and one in ConcreteStrengthComboBox. Updates to the combo box trigger an update of the ConcreteProperty attached to the combobox, not the other one (they are separate objects). The visible ConcreteProperty is unaffected.
To make this work, you need to move the signal attachment + the slot out of the combo box object. The following is a replacement for the two parts —
class ConcreteStrengthComboBox(QtWidgets.QComboBox):
def __init__(self, parent = None):
super(ConcreteStrengthComboBox, self).__init__(parent)
self.addItems(["C12/15","C16/20","C20/25","C25/30","C30/37","C35/45","C40/50","C45/55",
"C50/60","C55/67","C60/75","C70/85","C80/95","C90/105"])
self.setFont(QtGui.QFont("Helvetica", 10, QtGui.QFont.Normal, italic=False))
self.compressive_strength = ["12","16","20","25","30","35","40","45","50","55",
"60","70","80","90"]
class ConcreteStrengthInFo(QtWidgets.QWidget):
def __init__(self, parent=None):
super(ConcreteStrengthInFo, self).__init__(parent)
hbox = QtWidgets.QHBoxLayout()
concrete_strength = QtWidgets.QLabel("Concrete strength: ")
hbox.addWidget(concrete_strength)
self.concreteproperty = ConcreteProperty()
self.concretestrengthbox = ConcreteStrengthComboBox()
hbox.addWidget(self.concretestrengthbox)
self.concretestrengthbox.activated.connect(self.setdatastrength)
self.vlay = QtWidgets.QVBoxLayout()
self.vlay.addLayout(hbox)
self.vlay.addLayout(self.concreteproperty.concretestrength_lay)
#QtCore.pyqtSlot(int)
def setdatastrength(self, index):
it = self.concretestrengthbox.compressive_strength[index]
print(it)
self.concreteproperty.display_condata(it)
This works for me locally.
I am having troubled using the QHeaderView drag & drop feature. When I subclass a QHeaderView, I am able to accept drops with no issue. However, when I click on the QHeaderView and try to drag from one of the columns, nothing appears to happen.
Below I have re-implemented several drag events to simply print if they were called. However, only the dragEnterEvent is successful. No other event such as startDrag is ever called. My ultimate goal is to have a QTableView where I can drag columns from and to a QListWidget (essentially hiding the column) and the user can then drag the QListWidget item back onto the QTableView if they want the column and its data to be visible again. However, I can’t move forward until I can understand why the QHeaderView is not allowing me to drag. Any help would be greatly appreciated.
class MyHeader(QHeaderView):
def __init__(self, parent=None):
super().__init__(Qt.Horizontal, parent)
self.setDragEnabled(True)
self.setAcceptDrops(True)
def startDrag(self, *args, **kwargs):
print('start drag success')
def dragEnterEvent(self, event):
print('drag enter success')
def dragLeaveEvent(self, event):
print('drag leave success')
def dragMoveEvent(self, event):
print('drag move success')
class Form(QDialog):
def __init__(self, parent=None):
super().__init__(parent)
listWidget = QListWidget()
listWidget.setDragEnabled(True)
listWidget.setAcceptDrops(True)
listWidget.addItem('item #1')
listWidget.addItem('item #2')
tableWidget = QTableWidget()
header = MyHeader()
tableWidget.setHorizontalHeader(header)
tableWidget.setRowCount(5)
tableWidget.setColumnCount(2)
tableWidget.setHorizontalHeaderLabels(["Column 1", "Column 2"])
splitter = QSplitter(Qt.Horizontal)
splitter.addWidget(listWidget)
splitter.addWidget(tableWidget)
layout = QHBoxLayout()
layout.addWidget(splitter)
self.setLayout(layout)
if __name__=='__main__':
import sys
app = QApplication(sys.argv)
form= Form()
form.show()
sys.exit(app.exec_())
The QHeaderView class does not use the drag and drop methods inherited from QAbstractItemView, because it never needs to initiate a drag operation. Drag and drop is only used for rearranging columns, and it is not necessary to use the QDrag mechanism for that.
Given this, it will be necessary to implement custom drag and drop handling (using mousePressEvent, mouseMoveEvent and dropEvent), and also provide functions for encoding and decoding the mime-data format that Qt uses to pass items between views. An event-filter will be needed for the table-widget, so that dropping is still possible when all columns are hidden; and also for the list-widget, to stop it copying items to itself.
The demo script below implements all of that. There are probably some more refinements needed, but it should be enough to get you started:
import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class MyHeader(QHeaderView):
MimeType = 'application/x-qabstractitemmodeldatalist'
columnsChanged = pyqtSignal(int)
def __init__(self, parent=None):
super().__init__(Qt.Horizontal, parent)
self.setDragEnabled(True)
self.setAcceptDrops(True)
self._dragstartpos = None
def encodeMimeData(self, items):
data = QByteArray()
stream = QDataStream(data, QIODevice.WriteOnly)
for column, label in items:
stream.writeInt32(0)
stream.writeInt32(column)
stream.writeInt32(2)
stream.writeInt32(int(Qt.DisplayRole))
stream.writeQVariant(label)
stream.writeInt32(int(Qt.UserRole))
stream.writeQVariant(column)
mimedata = QMimeData()
mimedata.setData(MyHeader.MimeType, data)
return mimedata
def decodeMimeData(self, mimedata):
data = []
stream = QDataStream(mimedata.data(MyHeader.MimeType))
while not stream.atEnd():
row = stream.readInt32()
column = stream.readInt32()
item = {}
for count in range(stream.readInt32()):
key = stream.readInt32()
item[key] = stream.readQVariant()
data.append([item[Qt.UserRole], item[Qt.DisplayRole]])
return data
def mousePressEvent(self, event):
if event.button() == Qt.LeftButton:
self._dragstartpos = event.pos()
super().mousePressEvent(event)
def mouseMoveEvent(self, event):
if (event.buttons() & Qt.LeftButton and
self._dragstartpos is not None and
(event.pos() - self._dragstartpos).manhattanLength() >=
QApplication.startDragDistance()):
column = self.logicalIndexAt(self._dragstartpos)
data = [column, self.model().headerData(column, Qt.Horizontal)]
self._dragstartpos = None
drag = QDrag(self)
drag.setMimeData(self.encodeMimeData([data]))
action = drag.exec(Qt.MoveAction)
if action != Qt.IgnoreAction:
self.setColumnHidden(column, True)
def dropEvent(self, event):
mimedata = event.mimeData()
if mimedata.hasFormat(MyHeader.MimeType):
if event.source() is not self:
for column, label in self.decodeMimeData(mimedata):
self.setColumnHidden(column, False)
event.setDropAction(Qt.MoveAction)
event.accept()
else:
event.ignore()
else:
super().dropEvent(event)
def setColumnHidden(self, column, hide=True):
count = self.count()
if 0 <= column < count and hide != self.isSectionHidden(column):
if hide:
self.hideSection(column)
else:
self.showSection(column)
self.columnsChanged.emit(count - self.hiddenSectionCount())
class Form(QDialog):
def __init__(self, parent=None):
super().__init__(parent)
self.listWidget = QListWidget()
self.listWidget.setAcceptDrops(True)
self.listWidget.setDragEnabled(True)
self.listWidget.viewport().installEventFilter(self)
self.tableWidget = QTableWidget()
header = MyHeader(self)
self.tableWidget.setHorizontalHeader(header)
self.tableWidget.setRowCount(5)
self.tableWidget.setColumnCount(4)
labels = ["Column 1", "Column 2", "Column 3", "Column 4"]
self.tableWidget.setHorizontalHeaderLabels(labels)
for column, label in enumerate(labels):
if column > 1:
item = QListWidgetItem(label)
item.setData(Qt.UserRole, column)
self.listWidget.addItem(item)
header.hideSection(column)
header.columnsChanged.connect(
lambda count: self.tableWidget.setAcceptDrops(not count))
self.tableWidget.viewport().installEventFilter(self)
splitter = QSplitter(Qt.Horizontal)
splitter.addWidget(self.listWidget)
splitter.addWidget(self.tableWidget)
layout = QHBoxLayout()
layout.addWidget(splitter)
self.setLayout(layout)
def eventFilter(self, source, event):
if event.type() == QEvent.Drop:
if source is self.tableWidget.viewport():
self.tableWidget.horizontalHeader().dropEvent(event)
return True
else:
event.setDropAction(Qt.MoveAction)
return super().eventFilter(source, event)
if __name__=='__main__':
app = QApplication(sys.argv)
form = Form()
form.setGeometry(600, 50, 600, 200)
form.show()
sys.exit(app.exec_())
I'm having issues getting items with custom widgets to show up in a list widget. The items show up blank in the example below...
from PySide2 import QtWidgets
class ItemWidget(QtWidgets.QWidget):
def __init__(self,parent = None):
super(ItemWidget, self).__init__(parent)
layout = QtWidgets.QHBoxLayout()
self.setLayout(layout)
self.checkBox = QtWidgets.QCheckBox()
self.label = QtWidgets.QLabel('test')
layout.addWidget(self.checkBox)
layout.addWidget(self.label)
class ListWidget(QtWidgets.QListWidget):
def __init__(self,parent = None):
super(ListWidget,self).__init__(parent)
self.initUI()
def initUI(self):
for i in range(10):
item = QtWidgets.QListWidgetItem()
self.addItem(item)
widget = ItemWidget(self)
self.setItemWidget(item,widget)
self.show()
lister = ListWidget()
It looks like QlistWidget won't do what you want, so you'll need to approach it from a lower level.
PySide.QtGui.QListWidget.setItemWidget(item, widget)
This function should only be used to display static content in the place of a list widget item. If you want to display custom dynamic content or implement a custom editor widget, use PySide.QtGui.QListView and subclass PySide.QtGui.QItemDelegate instead.
I'm trying to implement the QAbstractListModel class in order to display several similar widgets.
The following code shows my problem:
import sys
from PyQt4 import QtCore
from PyQt4 import QtGui
class Model(QtCore.QAbstractListModel):
def __init__(self, parent=None):
super(QtCore.QAbstractListModel, self).__init__(parent)
self._widgets = []
def headerData(self, section, orientation, role):
""" Returns header for columns """
return "bla"
def rowCount(self, parentIndex=QtCore.QModelIndex()):
""" Returns number of interfaces """
return len(self._widgets)
def data(self, index, role):
""" Returns the data to be displayed """
if role == QtCore.Qt.DisplayRole:
row = index.row()
return self._widgets[row]
def insertRow(self, widget, parentIndex=QtCore.QModelIndex()):
""" Inserts a row into the model """
self.beginInsertRows(parentIndex, 0, 1)
self._widgets.append(widget)
self.endInsertRows()
class Widget(QtGui.QWidget):
def __init__(self, parent=None, name="None"):
super(QtGui.QWidget, self).__init__(parent)
self.layout = QtGui.QHBoxLayout()
self.setLayout(self.layout)
self.checkbox = QtGui.QCheckBox()
self.button = QtGui.QPushButton(self)
self.label = QtGui.QLabel(self)
self.label.setText(name)
self.layout.addWidget(self.checkbox)
self.layout.addWidget(self.button)
self.layout.addWidget(self.label)
class Window(QtGui.QMainWindow):
def __init__(self, parent=None):
super(QtGui.QMainWindow, self).__init__(parent)
self.view = QtGui.QListView(self)
self.model = Model()
self.view.setModel(self.model)
self.setCentralWidget(self.view)
self.model.insertRow(
widget=Widget(self)
)
self.model.insertRow(
widget=Widget(self)
)
self.model.insertRow(
widget=Widget(self)
)
self.model.insertRow(
widget=Widget(self)
)
self.show()
app = QtGui.QApplication(sys.argv)
window = Window()
sys.exit(app.exec_())
It works, there are four clickable entries in the list, but in only one of them the widget is actually displayed. Why is that?
I guess this behaviour is either caused by data() or how I'm using beginInsertRows(), but I can't figure out where the error is.
ìnsertRow() function now looks like that
def insertRow(self, widget, parentIndex=QtCore.QModelIndex()):
""" Inserts a row into the model """
self.beginInsertRows(parentIndex, len(self._widgets), len(self._widgets))
self._widgets.append(widget)
self.endInsertRows()
but it still does not work.
Actually, the four widgets are displayed. The issue is, they're all displayed in the top left corner. You can see they overlap if you put names, here "1", "2", "3", "4":
Fixing the row numbers doesn't solve the issue. The widgets will be in the correct rows but will still be displayed on the top left. It is because data is supposed to return text for the display role.
To display simple widgets, I suggest using QListWidget and the setItemWidget method. Otherwise you'll have to use delegates.
self.beginInsertRows(parentIndex, 0, 1)
0 - start
1 - end
You refresh only first row during insert
self.beginInsertRows(parentIndex, len(self._widgets), len(self._widgets))
must be work. Don't remember this method
self.model.reset()
this refresh all list, without specific rows