Is there a way to create a custom animated / gif QCursor? - python

I am trying to create a custum animated cursor that replaces the regular cursor for when lengthy processes are taking place similar to here and here, however, I woud like mine to be animated, for example using a gif, just as it is the case with the standard Qt.WaitCursor. How can I do this? I found this solution regarding animated system tray icons, however, I didn't manage to adapt it for it to work with the cursor icon.
As a side note: When I try to execute pm.setAlphaChannel(bm) as stated in the first link it does not work for me and I get the following error:
'AttributeError: QPixmap' object has no attribute 'setAlphaChannel'
Which is odd because according to the documentation, QPixmap does have a setAlphaChannel method.

One possible solution is to create a class that handles the update of the cursor of a given widget. In the following example the cursor is set when the start button is pressed and the cursor is restored when the stop button is pressed:
from PyQt5 import QtCore, QtGui, QtWidgets
class ManagerCursor(QtCore.QObject):
def __init__(self, parent=None):
super(ManagerCursor, self).__init__(parent)
self._movie = None
self._widget = None
self._last_cursor = None
def setMovie(self, movie):
if isinstance(self._movie, QtGui.QMovie):
if not self._movie != QtGui.QMovie.NotRunning:
self._movie.stop()
del self._movie
self._movie = movie
self._movie.frameChanged.connect(self.on_frameChanged)
self._movie.started.connect(self.on_started)
self._movie.finished.connect(self.restore_cursor)
def setWidget(self, widget):
self._widget = widget
#QtCore.pyqtSlot()
def on_started(self):
if self._widget is not None:
self._last_cursor = self._widget.cursor()
#QtCore.pyqtSlot()
def restore_cursor(self):
if self._widget is not None:
if self._last_cursor is not None:
self._widget.setCursor(self._last_cursor)
self._last_cursor = None
#QtCore.pyqtSlot()
def start(self):
if self._movie is not None:
self._movie.start()
#QtCore.pyqtSlot()
def stop(self):
if self._movie is not None:
self._movie.stop()
self.restore_cursor()
#QtCore.pyqtSlot()
def on_frameChanged(self):
pixmap = self._movie.currentPixmap()
cursor = QtGui.QCursor(pixmap)
if self._widget is not None:
if self._last_cursor is None:
self._last_cursor = self._widget.cursor()
self._widget.setCursor(cursor)
class Widget(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Widget, self).__init__(parent)
start_btn = QtWidgets.QPushButton("start", clicked=self.on_start)
stop_btn = QtWidgets.QPushButton("stop", clicked=self.on_stop)
self._manager = ManagerCursor(self)
movie = QtGui.QMovie("loading-icon.gif")
self._manager.setMovie(movie)
self._manager.setWidget(self)
lay = QtWidgets.QVBoxLayout(self)
lay.addWidget(start_btn)
lay.addWidget(stop_btn)
lay.addStretch()
#QtCore.pyqtSlot()
def on_start(self):
self._manager.start()
#QtCore.pyqtSlot()
def on_stop(self):
self._manager.stop()
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
w = Widget()
w.resize(640, 480)
w.show()
sys.exit(app.exec_())

Related

Move focus to another widget when the return or right arrow key is pressed?

I have a Qt widget that looks like this:
class launchiiwidget(QtWidgets.QWidget):
def __init__(self):
super().__init__()
layout = QtWidgets.QVBoxLayout(self)
self.textbox = QtWidgets.QTextEdit(self)
self.textbox.setLineWrapMode(QtWidgets.QTextEdit.NoWrap)
self.textbox.setAlignment(QtCore.Qt.AlignCenter)
self.textbox.setFixedSize(QtCore.QSize(600, 100))
self.textbox.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
self.textbox.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
layout.addWidget(self.textbox)
font = self.textbox.font()
font.setPointSize(80)
self.textbox.setFont(font)
self.listwidget = QtWidgets.QListWidget(self)
self.listwidget.addItem("Red")
self.listwidget.addItem("Blue")
layout.addWidget(self.listwidget)
if __name__ == "__main__":
app = QtWidgets.QApplication([])
widget = launchiiwidget()
widget.setWindowFlags(QtCore.Qt.FramelessWindowHint)
widget.resize(600, 200)
widget.show()
sys.exit(app.exec())
How can I make it so when the "return" or "right arrow key" is pressed, focus moves from wherever it is currently to the first item in listwidget? This should also work while being focused inside of textbox, without triggering a newline.
Note: items get dynamically added to listwidget.
A possible solution could be to use QShorcut but because the OP requires "without triggering a newline". So in this case the solution is to implement an eventfilter to the QWindow:
import sys
from PyQt6 import QtCore, QtGui, QtWidgets
class KeyHelper(QtCore.QObject):
pressed = QtCore.pyqtSignal()
def __init__(self, window):
super().__init__(window)
self._window = window
self.window.installEventFilter(self)
#property
def window(self):
return self._window
def eventFilter(self, obj, event):
if event.type() == QtCore.QEvent.Type.KeyPress:
if event.key() in (
QtCore.Qt.Key.Key_Return,
QtCore.Qt.Key.Key_Enter,
QtCore.Qt.Key.Key_Right,
):
self.pressed.emit()
return True
return super().eventFilter(obj, event)
class Launchiiwidget(QtWidgets.QWidget):
def __init__(self):
super().__init__()
self.textbox = QtWidgets.QTextEdit()
self.textbox.setLineWrapMode(QtWidgets.QTextEdit.LineWrapMode.NoWrap)
self.textbox.setAlignment(QtCore.Qt.AlignmentFlag.AlignCenter)
self.textbox.setFixedSize(QtCore.QSize(600, 100))
self.textbox.setVerticalScrollBarPolicy(
QtCore.Qt.ScrollBarPolicy.ScrollBarAlwaysOff
)
self.textbox.setHorizontalScrollBarPolicy(
QtCore.Qt.ScrollBarPolicy.ScrollBarAlwaysOff
)
font = self.textbox.font()
font.setPointSize(80)
self.textbox.setFont(font)
self.listwidget = QtWidgets.QListWidget()
self.listwidget.addItem("Red")
self.listwidget.addItem("Blue")
layout = QtWidgets.QVBoxLayout(self)
layout.addWidget(self.textbox)
layout.addWidget(self.listwidget)
def update_focus(self):
self.listwidget.setFocus()
index = self.listwidget.model().index(0, 0)
if index.isValid():
self.listwidget.setCurrentIndex(index)
if __name__ == "__main__":
app = QtWidgets.QApplication([])
widget = Launchiiwidget()
widget.setWindowFlags(QtCore.Qt.WindowType.FramelessWindowHint)
widget.resize(600, 200)
widget.show()
key_helper = KeyHelper(widget.windowHandle())
key_helper.pressed.connect(widget.update_focus)
sys.exit(app.exec())

PyQt5 passing argument between two classes: lambda vs partial

I am trying to pass an argument between two PyQt5 classes. I used three methods:
Using lambda functions.
Wrapper function (similar to lambda function).
partial from functools module.
In the example below, I have two windows:
MainWindow has QLineEdit mw_line_edit and a QPushButton mw_open_new_dialog_button.
Dialog: has a QLineEdit line_edit and aQPushButton push_button.
When I click the button push_button, I want it to insert the content of line_edit to mw_line_edit.
Here is a minimal example:
import sys
from functools import partial
from PyQt5 import QtWidgets, QtGui, QtCore
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.central_widget = QtWidgets.QWidget(self)
self.setCentralWidget(self.central_widget)
self.mw_open_new_dialog_button = QtWidgets.QPushButton('Open New dialog', self)
self.mw_line_edit = QtWidgets.QLineEdit(self)
self.hlayout = QtWidgets.QHBoxLayout(self)
self.hlayout.addWidget(self.mw_open_new_dialog_button)
self.hlayout.addWidget(self.mw_line_edit)
self.central_widget.setLayout(self.hlayout)
self.mw_open_new_dialog_button.clicked.connect(self.open_new_dialog)
def open_new_dialog(self):
self.dlg = Dialog()
#self.dlg.clicked.connect(partial(self.write_something, self.dlg.line_edit.text())) # <<<<<<< This does not work
self.dlg.clicked.connect(lambda: self.write_something(self.dlg.line_edit.text())) # this works
#self.dlg.clicked.connect(self.wrapper(self.dlg.line_edit.text()))# <<<<<<<<<<This does not work
self.dlg.exec()
#QtCore.pyqtSlot()
def write_something(self, text):
self.mw_line_edit.setText(text)
def wrapper(self, text):
return lambda: self.write_something(text)
class Dialog(QtWidgets.QDialog):
clicked = QtCore.pyqtSignal()
def __init__(self, parent=None):
super(QtWidgets.QDialog, self).__init__(parent)
self.hlayout = QtWidgets.QHBoxLayout(self)
self.line_edit = QtWidgets.QLineEdit(self)
self.push_button = QtWidgets.QPushButton('Click me', self)
self.hlayout.addWidget(self.line_edit)
self.hlayout.addWidget(self.push_button)
self.label = QtWidgets.QLabel('I am a Qlabel', self)
self.hlayout.addWidget(self.label)
self.setLayout(self.hlayout)
self.push_button.clicked.connect(self.clicked)
def write_something(self, text):
print(text)
app = QtWidgets.QApplication(sys.argv)
main_window = MainWindow()
main_window.show()
sys.exit(app.exec())
As you can see in the commented lines, only the following method works:
self.dlg.clicked.connect(lambda: self.write_something(self.dlg.line_edit.text()))
Why the other two do not work, i.e:
self.dlg.clicked.connect(partial(self.write_something, self.dlg.line_edit.text())) # <<<<<<< This does not work
self.dlg.clicked.connect(self.wrapper(self.dlg.line_edit.text()))# <<<<<<<<<<This does not work
Thanks
1) functools.partial()
What arguments are you passing to partial? You are passing the method write_something and the text of self.dlg.line_edit at the time the connection is made.
And what is the value of that text? it is an empty string, this explains the failure.
Is there any solution for this case? Yes, instead of passing the text, pass the QLineEdit, and in the method write_something get the text and set it in the other QLineEdit:
def open_new_dialog(self):
self.dlg = Dialog()
self.dlg.clicked.connect(partial(self.write_something, self.dlg.line_edit))
self.dlg.exec()
def write_something(self, le):
self.mw_line_edit.setText(le.text())
2) wrapper
It is the same problem, you are passing the empty text that you have at the moment of the connection
Is there any solution? Yes, the same solution as the previous one.
def open_new_dialog(self):
self.dlg = Dialog()
self.dlg.clicked.connect(self.wrapper(self.dlg.line_edit))
self.dlg.exec()
def write_something(self, text):
self.mw_line_edit.setText(text)
def wrapper(self, line):
return lambda: self.write_something(line.text())
Will there be a clean solution? Yes, create a signal that transports the text when you click.
from PyQt5 import QtWidgets, QtGui, QtCore
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
central_widget = QtWidgets.QWidget()
self.setCentralWidget(central_widget)
self.mw_open_new_dialog_button = QtWidgets.QPushButton('Open New dialog')
self.mw_line_edit = QtWidgets.QLineEdit()
hlayout = QtWidgets.QHBoxLayout(central_widget)
hlayout.addWidget(self.mw_open_new_dialog_button)
hlayout.addWidget(self.mw_line_edit)
self.mw_open_new_dialog_button.clicked.connect(self.open_new_dialog)
#QtCore.pyqtSlot()
def open_new_dialog(self):
self.dlg = Dialog()
self.dlg.textSignal.connect(self.mw_line_edit.setText)
self.dlg.exec()
class Dialog(QtWidgets.QDialog):
textSignal = QtCore.pyqtSignal(str)
def __init__(self, parent=None):
super(QtWidgets.QDialog, self).__init__(parent)
hlayout = QtWidgets.QHBoxLayout(self)
self.line_edit = QtWidgets.QLineEdit()
self.push_button = QtWidgets.QPushButton('Click me')
hlayout.addWidget(self.line_edit)
hlayout.addWidget(self.push_button)
self.label = QtWidgets.QLabel('I am a Qlabel')
hlayout.addWidget(self.label)
self.push_button.clicked.connect(self.sendText)
#QtCore.pyqtSlot()
def sendText(self):
self.textSignal.emit(self.line_edit.text())
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
main_window = MainWindow()
main_window.show()
sys.exit(app.exec())

PyQt5 context menu for QTableWidget column head

is there a way to get a context menu on a tables column head.
Find nothing about that in PyQt5's tuts.
the table's context menu is simple but the column heads don't affect.
# dlg is a QDialog object
self.tbl = QtWidgets.QTableWidget(dlg)
self.tbl.setContextMenuPolicy( Qt.CustomContextMenu )
You have to use the QHeaderView of the QTableWidget:
from PyQt5 import QtCore, QtWidgets
class Dialog(QtWidgets.QDialog):
def __init__(self, parent=None):
super(Dialog, self).__init__(parent)
self.tbl = QtWidgets.QTableWidget(10, 10, self)
for w in (self.tbl.horizontalHeader(), self.tbl.verticalHeader(), self.tbl):
w.setContextMenuPolicy(QtCore.Qt.CustomContextMenu)
w.customContextMenuRequested.connect(self.on_customContextMenuRequested)
lay = QtWidgets.QVBoxLayout(self)
lay.addWidget(self.tbl)
#QtCore.pyqtSlot(QtCore.QPoint)
def on_customContextMenuRequested(self, pos):
widget = self.sender()
if isinstance(widget, QtWidgets.QAbstractItemView):
widget = widget.viewport()
menu = QtWidgets.QMenu()
menu.addAction("Foo Action")
menu.exec_(widget.mapToGlobal(pos))
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
w = Dialog()
w.show()
sys.exit(app.exec_())
Update:
class Dialog(QtWidgets.QDialog):
def __init__(self, parent=None):
super(Dialog, self).__init__(parent)
self.tbl = QtWidgets.QTableWidget(10, 10, self)
self.tbl.setContextMenuPolicy(QtCore.Qt.CustomContextMenu)
self.tbl.customContextMenuRequested.connect(self.on_customContextMenuRequested_tw)
self.tbl.verticalHeader().setContextMenuPolicy(QtCore.Qt.CustomContextMenu)
self.tbl.verticalHeader().customContextMenuRequested.connect(self.on_customContextMenuRequested_vh)
self.tbl.horizontalHeader().setContextMenuPolicy(QtCore.Qt.CustomContextMenu)
self.tbl.horizontalHeader().customContextMenuRequested.connect(self.on_customContextMenuRequested_hh)
lay = QtWidgets.QVBoxLayout(self)
lay.addWidget(self.tbl)
#QtCore.pyqtSlot(QtCore.QPoint)
def on_customContextMenuRequested_tw(self, pos):
menu = QtWidgets.QMenu()
menu.addAction("Foo Action TW")
menu.exec_(self.tbl.viewport().mapToGlobal(pos))
#QtCore.pyqtSlot(QtCore.QPoint)
def on_customContextMenuRequested_vh(self, pos):
menu = QtWidgets.QMenu()
menu.addAction("Foo Action VH")
menu.exec_(self.tbl.verticalHeader().mapToGlobal(pos))
#QtCore.pyqtSlot(QtCore.QPoint)
def on_customContextMenuRequested_hh(self, pos):
menu = QtWidgets.QMenu()
menu.addAction("Foo Action HH")
menu.exec_(self.tbl.horizontalHeader().mapToGlobal(pos))
You need to set the context menu policy on the header itself (if I've understood correctly), so...
self.tbl = QtWidgets.QTableWidget(dlg)
self.tbl.horizontalHeader().setContextMenuPolicy(Qt.CustomContextMenu)
and connect to the `QHeaderView::customContextMenuRequested signal...
self.tbl.horizontalHeader().customContextMenuRequested.connect(self.handle_context_menu_request)

PyQt: How to get UI data from a QThread

I have the following code but it's complaining that I cannot access the UI data from my thread. In my example code below, What is the best way I can access the userInputString value so my threading can run?
self.nameField is a PyQt QLineEdit.
QObject::setParent: Cannot set parent, new parent is in a different thread
QPixmap: It is not safe to use pixmaps outside the GUI thread
QWidget::repaint: Recursive repaint detected
import myUI
class MainUIClass(QtGui.QMainWindow, myUI.Ui_MainWindow):
def __init__(self, parent=None):
super(MainUIClass, self).__init__(parent)
self.setupUi(self)
self.startbutton.clicked.connect(self.do_work)
self.workerThread = WorkerThread()
self.connect(self.workerThread, SIGNAL("myThreading()"), self.myThreading, Qt.DirectConnection)
def do_work(self):
self.userInputString = self.nameField.Text()
self.workerThread.start()
def myThreading(self):
if userInputString is not None:
#Do something
class WorkerThread(QThread):
def __init__(self, parent=None):
super(WorkerThread, self).__init__(parent)
def run(self):
self.emit(SIGNAL("myThreading()"))
if __name__ == '__main__':
a = QtGui.QApplication(sys.argv)
app = MainUIClass()
app.show()
a.exec_()
Not sure if it's what you need but here is a working QThread exemple using Qt5
import time
import sys
from PyQt5 import QtWidgets, QtGui, QtCore
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.worker_thread = WorkerThread()
self.worker_thread.job_done.connect(self.on_job_done)
self.create_ui()
def create_ui(self):
self.button = QtWidgets.QPushButton('Test', self)
self.button.clicked.connect(self.start_thread)
layout = QtWidgets.QVBoxLayout(self)
layout.addWidget(self.button)
def start_thread(self):
self.worker_thread.gui_text = self.button.text()
self.worker_thread.start()
def on_job_done(self, generated_str):
print("Generated string : ", generated_str)
self.button.setText(generated_str)
class WorkerThread(QtCore.QThread):
job_done = QtCore.pyqtSignal('QString')
def __init__(self, parent=None):
super(WorkerThread, self).__init__(parent)
self.gui_text = None
def do_work(self):
for i in range(0, 1000):
print(self.gui_text)
self.job_done.emit(self.gui_text + str(i))
time.sleep(0.5)
def run(self):
self.do_work()
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
test = MainWindow()
test.show()
app.exec_()

PyQt application close with error

I have some trouble with creating window application using PyQt. For example: we have the following class for GUI:
class SampleMainWindow(QtGui.QMainWindow):
def __init__(self, parent=None):
...
def hideEvent(self, event):
...
def showEvent(self, event):
...
def activate(self):
...
def closeEvent(self, event):
...
What if we want to use it just for showing results and acept user inputs, and for all control logic we have another class, which use the instance of SampleMainWindow as a field:
class Programm:
def __init__(self):
self.window = SampleMainWindow()
....
app = QtGui.QApplication(sys.argv)
prog = Programm()
prog.window.show()
app.exec_()
So, if we create the instance of Programm, the application will run well, but on close we'll get an error that python.exe process could not be completed normally. But if the instance of SampleMainWindow is not a field of class:
class Programm:
def __init__(self):
win = SampleMainWindow()
....
application close well. What's the reason?
Here are the full version of Gui class:
class SampleMainWindow(QtGui.QMainWindow):
def initTray(self):
self.icon = QtGui.QSystemTrayIcon()
self.icon.setIcon(QtGui.QIcon('Tray.png'))
self.icon.show()
self.icon.activated.connect(self.activate)
def __init__(self, parent=None):
QtGui.QMainWindow.__init__(self)
moduleglobalconstants.APP_RUNNING = True
self.initTray()
self.newSession = True
self.setGeometry(300, 300, 600, 400)
self.setWindowTitle('Eye: Recently Added Lines')
self.statusBar().showMessage('Ready')
exitAction = QtGui.QAction(QtGui.QIcon('Exit.png')
,'Exit'
,self)
exitAction.setShortcut('Ctrl+Q')
exitAction.setStatusTip('Exit application')
self.connect(exitAction
,QtCore.SIGNAL('triggered()')
,QtCore.SLOT('close()'))
menubar = self.menuBar()
fileMenu = menubar.addMenu('&File')
fileMenu.addAction(exitAction)
self.toolbar = self.addToolBar('Exit')
self.toolbar.addAction(exitAction)
self.textEdit = QtGui.QTextEdit()
self.scrollPosition = self.textEdit.textCursor()
self.textEdit.setReadOnly(True)
self.setCentralWidget(self.textEdit)
def hideEvent(self, event):
self.hidden = True
self.setWindowFlags(QtCore.Qt.ToolTip)
self.setVisible(False)
def showEvent(self, event):
self.hidden = False
self.setVisible(True)
def activate(self):
self.setWindowFlags(QtCore.Qt.Window)
self.show()
self.setWindowState(self.windowState() & ~QtCore.Qt.WindowMinimized | QtCore.Qt.WindowActive)
self.activateWindow()
def questionDialog(self, caption = 'Message',text = "Are you sure?"):
self.activate()
msgBox = QtGui.QMessageBox(self)
msgBox.setWindowTitle("Eye")
msgBox.setText(caption);
msgBox.setInformativeText(text);
msgBox.setStandardButtons(QtGui.QMessageBox.Yes| QtGui.QMessageBox.No);
msgBox.setDefaultButton(QtGui.QMessageBox.Yes);
return msgBox.exec_()
def criticalDialog(self,app, caption = 'Eye: Critical Error',text = "Impossible to continue working!"):
self.activate()
msgBox = QtGui.QMessageBox.critical(self,caption,text)
moduleglobalconstants.APP_RUNNING = False
def closeEvent(self, event):
reply = self.questionDialog()
if reply == QtGui.QMessageBox.Yes:
moduleglobalconstants.APP_RUNNING = False
event.accept()
else:
event.ignore()
def showNewLines(self, singleLine = None, lines = None, mode='insert'):
if (mode == 'rewrite'):
self.textEdit.clear()
if lines:
for line in lines:
self.textEdit.insertPlainText(line.strip() + "\n")
elif singleLine:
self.textEdit.insertPlainText(singleLine.strip()+"\n")
This has to do with python's garbage collecting - as (almost) soon an object isn't referenced anymore it destroys it, so I guess the process doesn't terminate as long as the window wasn't garbage-collected.
You can try to add at the end del Programm.window or something like that (there's probably a better way of doing this, but I never programmed QT myself so I can't help you here)
see this:
from PyQt4.QtCore import *
from PyQt4.QtGui import *
import sys
class MyWindow(QWidget):
def __init__(self, parent=None):
QWidget.__init__(self, parent)
self.label = QLabel("Hi, I'm a window", self)
self.button = QPushButton("&Quit", self)
self.connect(self.button, SIGNAL("clicked()"), QCoreApplication.instance(), SLOT("quit()"))
lay = QVBoxLayout()
lay.addWidget(self.label)
lay.addWidget(self.button)
self.setLayout(lay)
def closeEvent(self, event):
print "Closing the app"
self.deleteLater()
if __name__ == '__main__':
app = QApplication(sys.argv)
mw = MyWindow()
mw.show()
sys.exit(app.exec_())
the solution is to implement closeEvent method

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