I'm struggling with making the transition from Tkinter to the more object-oriented approach of PyQt. My particular question focuses on combining file dialogs with buttons. In the example below, having lines of code I admittedly don't completely understand, I use a file dialog to load a time series, stored as a .csv file, into a dataframe and then plot it:
import sys
import pandas as pd
from matplotlib import pyplot as plt
from PyQt5.QtWidgets import QApplication, QWidget, QFileDialog,
class App(QWidget):
def __init__(self):
super().__init__()
self.title = 'Series Plotter'
self.left = 10
self.top = 10
self.width = 640
self.height = 480
self.initUI()
def initUI(self):
self.setWindowTitle(self.title)
self.setGeometry(self.left, self.top, self.width, self.height)
self.openFileNameDialog()
self.show()
def openFileNameDialog(self):
options = QFileDialog.Options()
options |= QFileDialog.DontUseNativeDialog
fileName, _ = QFileDialog.getOpenFileName(self,"Choose File", "","csv (*.csv)",
options=options)
df=pd.read_csv(fileName)
df.plot()
plt.show()
if __name__ == '__main__':
app = QApplication(sys.argv)
ex = App()
sys.exit(app.exec_())
This works insofar as it automatically launches a file dialog and plots the chosen time series. However, I'd prefer to do the following:
Have an "open file" button in my window to launch the file dialog.
Have a "plot series" button in my window to plot the selected series. I imagine this button would need to be disabled until the series is actually chosen.
Despite looking at various tutorials, I'm struggling to find the pythonic way of doing this, a fact I attribute to my limited knowledge of the objected-oriented approach.
You can try to create a main window and add button there, and connect button click event to a function where you initialize the class you have created, something like this:
from PyQt5 import QtWidgets
class MainWindow(QtWidgets.QMainWindow):
def __init__(self):
super(MainWindow, self).__init__()
self.resize(300,300)
frame =QtWidgets.QFrame()
self.setCentralWidget(frame)
layout = QtWidgets.QHBoxLayout()
frame.setLayout(layout)
self.fileOpenButton = QtWidgets.QPushButton('Click to open File Dialog',self)
layout.addWidget(self.fileOpenButton)
self.fileOpenButton.clicked.connect(self.buttonClicked)
def buttonClicked(self):
wig = App()
def main():
app = QApplication([])
mainWindow = MainWindow()
mainWindow.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
The output:
After clicking the button:
After selecting a file:
Related
I started out with PyQt5 recently. I wanted to create a custom widget and then insert it into the main window of an application.
The custom Widget:
class ScoreCard(QtWidgets.QWidget):
def __init__(self, parent=None):
super(ScoreCard, self).__init__(parent=parent)
self.setWindowFlags(QtCore.Qt.CustomizeWindowHint)
self.pressing = False
self.init_ui()
self.show()
def init_ui(self):
# Layout in here
And this is the main Application:
from PyQt5.QtWidgets import *
from scorecard import ScoreCard
import sys
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
self.initUi()
self.show()
def initUi(self):
self.setGeometry(300,300,800,700)
window_layout = QVBoxLayout()
recent_playcard = ScoreCard()
window_layout.addWidget(recent_playcard)
self.setLayout(window_layout)
if __name__ == "__main__":
app = QApplication(sys.argv)
execute = MainWindow()
sys.exit(app.exec_())
Why is it that whenever I run the main Application, the custom widget appears in another window? I even tried removing the frame and setting the parent to none, but none of that changed this behavior. How do I fix this?
Looks like I mixed up QMainWindow and QDialog I should be using a central widget for the main application instead of setting a layout..
I am trying to create a simple GUI using PyQt5. I am running my code in windows 10 from Spyder(Anaconda latest version, python 3.7). Here is my code:
import sys
from PyQt5.QtWidgets import QApplication, QWidget, QPushButton
from PyQt5.QtGui import QIcon
from PyQt5.QtCore import pyqtSlot
class App(QWidget):
def __init__(self):
super().__init__()
self.title = 'PyQt5 button test'
self.left = 50
self.top = 50
self.width = 720
self.height = 800
self.initUI()
def initUI(self):
self.setWindowTitle(self.title)
self.setGeometry(self.left, self.top, self.width, self.height)
button = QPushButton('PyQt5 button', self)
button.setToolTip('This is an example button')
button.move(100,70)
button.clicked.connect(self.on_click)
self.show()
#pyqtSlot()
def on_click(self):
print('PyQt5 button click')
if __name__ == '__main__':
app = QApplication(sys.argv)
ex = App()
app.exec_()
A window pop up. Now if I close the GUI by clicking on closing button(top right corner of the GUI),Spyder IP console does not return to normal condition. It freezes. What should I use in code to solve the issue?
Thanks,
Moni
Closing the window doesn't appear to close the QApplication object. To do this, override the closeEvent function of the main window by adding these two lines after the on_Click definition
def closeEvent(self,event):
QApplication.quit()
This will close the window and the QApplication object as well and control should return to the console
You can try and look at the answer in the following thread:
Can't Kill PyQT Window after closing it. Which requires me to restart the kernal
Seems to have resemblance to your problem and a solution.
I need to generate a custom popup input window triggered by clicking a QPushButton in my app (via clicked). It needs to get several inputs from the user of different types and then return them to the calling function inside the main window app. I have found built in functions such as QInputDialog that can do this for single specific inputs, but I can't figure out how to do this in the case of a popup that asks for several inputs of different types at once (preferably in a window designed in Qt Designer). Does anyone know how to do this?
import sys
import os
from PyQt5.QtWidgets import QMainWindow, QApplication
from PyQt5 import uic
path = os.path.dirname(__file__) #uic paths from itself, not the active dir, so path needed
qtCreatorFile = "NAME.ui" #Ui file name, from QtDesigner
Ui_MainWindow, QtBaseClass = uic.loadUiType(path + qtCreatorFile) #process through pyuic
class MyApp(QMainWindow, Ui_MainWindow): #gui class
def __init__(self):
#Set up the gui via Qt
super(MyApp, self).__init__()
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
self.ui.add_button.clicked.connect(self.add_row) #add_button is QPushButton
def add_row(self):
data1, data2, data3 = #popup form to get data (types are not the same)
#do stuff with data
pass
#start app
if __name__ == "__main__":
app = QApplication(sys.argv) #instantiate a QtGui (holder for the app)
window = MyApp()
window.show()
sys.exit(app.exec_())
There is no single solution but I will give you a guide to do what you want.
If you want to get a widget with the behavior of QInputDialog you must first choose the right template, in this case a good option is Dialog with Buttons Bottom or Dialog with Buttons Right, add the components you want, position it, etc.
Then as you show your code you create a class that inherits from QDialog and then create a method where you get the results but to do so do not use show() but exec_()
path = os.path.dirname(__file__)
qtCreatorFile = "some_dialog.ui"
Ui_Dialog, _ = uic.loadUiType(os.path.join(path,qtCreatorFile))
class CustomDialog(QDialog, Ui_Dialog):
def __init__(self):
super(CustomDialog, self).__init__()
self.setupUi(self)
# set initials values to widgets
def getResults(self):
if self.exec_() == QDialog.Accepted:
# get all values
val = self.some_widget.some_function()
val2 = self.some_widget2.some_another_function()
return val1, val2, ...
else:
return None
And then use it in your function:
class MyApp(QMainWindow, Ui_MainWindow): #gui class
def __init__(self):
#Set up the gui via Qt
super(MyApp, self).__init__()
self.setupUi(self)
self.add_button.clicked.connect(self.add_row) #add_button is QPushButton
def add_row(self):
w = CustomDialog()
values = w.getResults()
if values:
data1, data2, data3 = values
I am trying to write a PyQt5 application that does the following:
Creates and opens a Main Window. The MainWindow has a function that opens a QFileDialog window.
Function to open QFileDialog can be triggered in two ways (1) from a file menu option called 'Open' (2) automatically, after the Main window is shown.
My problem is that I haven't found a way to get the QfileDialog to automatically open (2) that doesn't cause the application to hang when the main window is closed. Basic example of code can be found below:
import sys
from PyQt5.QtWidgets import (QApplication, QMainWindow, QMenuBar, QWidget,
QHBoxLayout, QCalendarWidget, QScrollArea, QFileDialog, QAction, QFrame)
from PyQt5.QtGui import QIcon
from PyQt5.QtCore import Qt
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.openAction = QAction(QIcon('/usr/share/icons/breeze/places/64/folder-open.svg'), 'Open', self)
self.openAction.triggered.connect(self.openDialog)
self.menubar = QMenuBar(self)
fileMenu = self.menubar.addMenu('&File')
fileMenu.addAction(self.openAction)
self.event_widgets = EventWidgets(self)
self.setMenuBar(self.menubar)
self.setCentralWidget(self.event_widgets)
def openDialog(self):
ics_path = QFileDialog.getOpenFileName(self, 'Open file', '/home/michael/')
class EventWidgets(QWidget):
def __init__(self, parent):
super(EventWidgets, self).__init__(parent)
self.initUI()
def initUI(self):
self.calendar = QCalendarWidget(self)
self.frame = QFrame()
self.scrollArea = QScrollArea()
self.scrollArea.setWidget(self.frame)
horizontal_box = QHBoxLayout()
horizontal_box.addWidget(self.calendar)
horizontal_box.addWidget(self.scrollArea)
self.setLayout(horizontal_box)
if __name__ == '__main__':
app = QApplication(sys.argv)
app_window = MainWindow()
app_window.showMaximized()
app_window.openDialog()
sys.exit(app.exec_())
Code has been tested on KDE Neon and Arch Linux, both have same issue.
I can get round this issue by handling the close event of the Main Window manually - i.e. adding this function to MainWindow:
def closeEvent(self, event):
sys.exit()
But I am not sure a) why this is necessary b) if it is best practice.
I tried your code on macOS Sierra and it works as it's supposed to. However I would propose a different approach to solve your problem.
What you could do is to implement the showEvent() function in your MainWindow class, which is executed whenever a widget is displayed (either using .show() or .showMaximized()) and trigger your custom slot to open the QFileDialog. When doing this you could make use of a single shot timer to trigger the slot with some minimal delay: the reason behind this is that if you simply open the dialog from within the showEvent(), you will see the dialog window but not the MainWindow below it (because the QFileDialog is blocking the UI until the user perform some action). The single shot timer adds some delay to the opening of the QFileDialog, and allows the MainWindow to be rendered behind the modal dialog. Here is a possible solution (not that I made some minor changes to your code, which you should be able to easily pick up):
import sys
from PyQt5 import QtCore
from PyQt5 import QtWidgets
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.openAction = QtWidgets.QAction('Open', self)
self.openAction.triggered.connect(self.openDialog)
menuBar = self.menuBar()
fileMenu = menuBar.addMenu('&File')
fileMenu.addAction(self.openAction)
self.event_widgets = EventWidgets(self)
self.setCentralWidget(self.event_widgets)
def showEvent(self, showEvent):
QtCore.QTimer.singleShot(50, self.openDialog)
#QtCore.pyqtSlot()
def openDialog(self):
ics_path = QtWidgets.QFileDialog.getOpenFileName(self, 'Open file', '/Users/daniele/')
class EventWidgets(QtWidgets.QWidget):
def __init__(self, parent):
super(EventWidgets, self).__init__(parent)
self.calendar = QtWidgets.QCalendarWidget(self)
self.frame = QtWidgets.QFrame()
self.scrollArea = QtWidgets.QScrollArea()
self.scrollArea.setWidget(self.frame)
horizontal_box = QtWidgets.QHBoxLayout()
horizontal_box.addWidget(self.calendar)
horizontal_box.addWidget(self.scrollArea)
self.setLayout(horizontal_box)
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
app_window = MainWindow()
app_window.showMaximized()
sys.exit(app.exec_())
I have created two different pyqt windows, and within one of them, by pressing a button, it should bring up another smaller window. While my code does pretty much exactly what I just dais it should do, there is a problem with the way the smaller popup window is displayed.
This is my code for displaying the windows and the button functionality:
from PyQt4 import QtGui
from EnterprisePassport import Ui_StudentEnterprisePassport
from Session_tracker import Ui_Session_tracker
class StudentEnterprisePassport(Ui_StudentEnterprisePassport):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
self.setupUi(self)
self.sessionTracker_btn.clicked.connect(self.handleButton)
self.window2 = None
def handleButton(self):
if self.window2 is None:
self.window2 = Session_tracker(self)
self.window2.show()
class Session_tracker(Ui_Session_tracker):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
self.setupUi(self)
if __name__ == '__main__':
import sys
app = QtGui.QApplication(sys.argv)
window = StudentEnterprisePassport()
window.show()
sys.exit(app.exec_())
I can still use the functions within the window, but I can't move it, or close it, and there is no title bar. Have I done something wrong within my code for the popup window to appear like this?
Edit:
Original Session tracker window: Original window
Popup session tracker window: Popup window
In order to show the other widget in it's own window, it has to be a QMainWindow or a QDialog.
One option, if you don't want to convert your existing Session_tracker to a QDialog, is to just wrap it in a QDialog
def handleButton(self):
if self.window2 is None:
self.window2 = QtGui.QDialog(self)
lay = QtGui.QVBoxLayout()
self.window2.setLayout(lay)
self.session_tracker = Session_tracker(self.window2)
lay.addWidget(self.session_tracker)
self.window2.show()