Develop Reference

QFileDialog always opens behind main window

I'm trying to open a file in my PySide2 application, but the file dialog always opens below the main window and appears as another application in the launcher. The application's name is "Portal".
I see other answers where the solution is to pass the main window as the first parameter to getOpenFileName(), but that doesn't work for me.
Here's a simple demonstration of the problem:
import sys
from PySide2.QtWidgets import QPushButton, QFileDialog, QApplication
class DemoButton(QPushButton):
def __init__(self, text):
super().__init__(text)
self.clicked.connect(self.on_click)
def on_click(self):
file_name, _ = QFileDialog.getOpenFileName(
self,
"Open a text file.",
filter='Text file (*.txt)')
print(file_name)
def main():
app = QApplication(sys.argv)
button = DemoButton("Hello World")
button.show()
app.exec_()
sys.exit()
main()
I thought maybe the parent had to be a QMainWindow, so I tried that:
import sys
from PySide2 import QtWidgets
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
main_widget = QtWidgets.QWidget(self)
self.setCentralWidget(main_widget)
# layout initialize
g_layout = QtWidgets.QVBoxLayout()
layout = QtWidgets.QFormLayout()
main_widget.setLayout(g_layout)
# Add Widgets
self.exec_btn = QtWidgets.QPushButton('Execute')
self.exec_btn.clicked.connect(self.find_file)
# global layout setting
g_layout.addLayout(layout)
g_layout.addWidget(self.exec_btn)
def find_file(self):
file_name, _ = QtWidgets.QFileDialog.getOpenFileName(
self,
"Open a text file.",
filter='Text file (*.txt)')
print(file_name)
def main():
app = QtWidgets.QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec_()
sys.exit()
main()
The file dialog behaved exactly the same.
I'm using PySide2 5.12.2, Python 3.6.7, and running on Ubuntu 18.04.

Thanks to ekhumoro's comment, I learned that I can tell PySide2 not to use the native file dialog.
import sys
from PySide2.QtWidgets import QPushButton, QFileDialog, QApplication
class DemoButton(QPushButton):
def __init__(self, text):
super().__init__(text)
self.clicked.connect(self.on_click)
def on_click(self):
file_name, _ = QFileDialog.getOpenFileName(
self,
"Open a text file.",
filter='Text file (*.txt)',
options=QFileDialog.DontUseNativeDialog)
print(file_name)
def main():
app = QApplication(sys.argv)
button = DemoButton("Hello World")
button.show()
app.exec_()
sys.exit()
main()
That fixes the behaviour by bringing the file dialog to the front, but I think the native file dialog looks better. Hopefully, there's another option that can make the native file dialog work properly.

Internationalization (translation) of dialog and the main window in a pyqt5 application

I am trying to translate my small application written in pyside2/pyqt5 to several languages, for example, Chinese. After googling, I managed to change the main window to Chinese after select from the menu -> language -> Chinese. However, the pop up dialog from menu -> option still remains English version. It seems the translation info is not transferred to the dialog. How do I solve this?
Basically, I build two ui files in designer and convert to two python files:One mainui.py and one dialogui.py. I then convert the two python file into one *.ts file using
pylupdate5 -verbose mainui.py dialogui.py -ts zh_CN.ts
after that, in linguist input the translation words. I can see the items in the dialog, which means this information is not missing. Then I release the file as zh_CN.qm file. All this supporting file I attached below using google drive.
Supporting files for the question
The main file is as
import os
import sys
from PySide2 import QtCore, QtGui, QtWidgets
from mainui import Ui_MainWindow
from dialogui import Ui_Dialog
class OptionsDialog(QtWidgets.QDialog,Ui_Dialog):
def __init__(self,parent):
super().__init__(parent)
self.setupUi(self)
self.retranslateUi(self)
class MainWindow(QtWidgets.QMainWindow,Ui_MainWindow):
def __init__(self):
super().__init__()
self.setupUi(self)
self.actionConfigure.triggered.connect(self.showdialog)
self.actionChinese.triggered.connect(self.change_lang)
def showdialog(self):
dlg = OptionsDialog(self)
dlg.exec_()
def change_lang(self):
trans = QtCore.QTranslator()
trans.load('zh_CN')
QtCore.QCoreApplication.instance().installTranslator(trans)
self.retranslateUi(self)
if __name__=='__main__':
app = QtWidgets.QApplication(sys.argv)
mainWin = MainWindow()
mainWin.show()
ret = app.exec_()
sys.exit(ret)
I think it should be a typical task because almost no application will only have a mainwindow.

You have to overwrite the changeEvent() method and call retranslateUi() when the event is of type QEvent::LanguageChange, on the other hand the QTranslator object must be a member of the class but it will be deleted and it will not exist when the changeEvent() method is called.
Finally assuming that the Language menu is used to establish only translations, a possible option is to establish the name of the .qm as data of the QActions and to use the triggered method of the QMenu as I show below:
from PySide2 import QtCore, QtGui, QtWidgets
from mainui import Ui_MainWindow
from dialogui import Ui_Dialog
class OptionsDialog(QtWidgets.QDialog,Ui_Dialog):
def __init__(self,parent):
super().__init__(parent)
self.setupUi(self)
def changeEvent(self, event):
if event.type() == QtCore.QEvent.LanguageChange:
self.retranslateUi(self)
super(OptionsDialog, self).changeEvent(event)
class MainWindow(QtWidgets.QMainWindow,Ui_MainWindow):
def __init__(self):
super().__init__()
self.setupUi(self)
self.m_translator = QtCore.QTranslator(self)
self.actionConfigure.triggered.connect(self.showdialog)
self.menuLanguage.triggered.connect(self.change_lang)
# set translation for each submenu
self.actionChinese.setData('zh_CN')
#QtCore.Slot()
def showdialog(self):
dlg = OptionsDialog(self)
dlg.exec_()
#QtCore.Slot(QtWidgets.QAction)
def change_lang(self, action):
QtCore.QCoreApplication.instance().removeTranslator(self.m_translator)
if self.m_translator.load(action.data()):
QtCore.QCoreApplication.instance().installTranslator(self.m_translator)
def changeEvent(self, event):
if event.type() == QtCore.QEvent.LanguageChange:
self.retranslateUi(self)
super(MainWindow, self).changeEvent(event)
if __name__=='__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
mainWin = MainWindow()
mainWin.show()
ret = app.exec_()
sys.exit(ret)

Python3 and Qt Designer - Display an image in main window

I'm still new with python and Qt designer. I would like to develop an application where user need to press the 'pushbutton' in order to view the image(from local directory path) on GUI mainwindow.This will keep repeating until complete number of cycle.
Did tried using QLabel and QGraphiscView widget but doesn't work.(probably due to lack of knowledge). Could anyone help me to solve it?
Below is the code:
#!/usr/bin/env python
from __future__ import division
import sys
from PyQt4 import QtCore, QtGui, uic
gui_file = 'image.ui'
Ui_MainWindow, QtBaseClass = uic.loadUiType(gui_file)
class showImage(QtGui.QMainWindow,Ui_MainWindow):
def __init__(self):
QtGui.QMainWindow.__init__(self)
Ui_MainWindow.__init__(self)
self.setupUi(self)
self.get_image_button.clicked.connect(self.getImage)
def getImage(self):
image_path='c:/Users/mohd_faizal4/Desktop/Python/Image/image1.jpg' #path to image file
self.label_image.QPixmap(image_path)
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
myWindow = showImage()
myWindow.show()
sys.exit()
app.exec_()
Really appreciate!

Access QT Designer Objects Programmatically

Disclaimer: New to both python and qt designer
QT Designer 4.8.7
Python 3.4
PyCharm 5.0.3
Question - How do I add controls to the main form or a scroll area widget on the main form (created in QT Designer) programmatically?
I have created a MainWindow in qt designer and added my widgets. The following is the entire test program in PyCharm:
import sys
from PyQt4 import QtGui, QtCore, uic
from PyQt4.QtGui import *
from PyQt4.QtCore import *
qtCreatorFile = "programLauncher.ui"
Ui_MainWindow, QtBaseClass = uic.loadUiType(qtCreatorFile)
class MyApp(QtGui.QMainWindow, Ui_MainWindow):
def __init__(self):
QtGui.QMainWindow.__init__(self)
Ui_MainWindow.__init__(self)
self.setupUi(self)
# Cannot resize or maximize
self.setFixedSize(1045, 770)
# Add button test
self.dateLabel = QtGui.QLabel("Test")
self.pushButton = QtGui.QPushButton('Test button')
# self.scrollArea_programs.addWidget()
grid = QtGui.QGridLayout()
# self.scrollArea_programs.addWidget(self.pushButton)
grid.addWidget(self.dateLabel,0,0)
grid.addWidget(self.pushButton,0,1)
self.setLayout(grid)
self.pushButton_exit.clicked.connect(self.closeEvent)
def closeEvent(self):
QtGui.QApplication.quit()
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
window = MyApp()
window.show()
sys.exit(app.exec_())
As you can see I tried to add controls to a grid but nothing shows up when the program runs - I have also tried to add a control to the scroll area. Can someone help me to just add 1 control to the scroll area at run time - so then I can know the proper way to do it or "a" proper way to do this.
Thanks in advance

Without having access to your programLauncher.ui and making minimal changes to your posted code, you can add your UI elements to the window like so:
from PyQt4 import QtGui
import sys
class MyApp(QtGui.QMainWindow):
def __init__(self):
QtGui.QMainWindow.__init__(self)
# Cannot resize or maximize
self.setFixedSize(1045, 770)
widget = QtGui.QWidget(self)
self.setCentralWidget(widget)
# Add button test
self.dateLabel = QtGui.QLabel("Test")
self.pushButton = QtGui.QPushButton('Test button')
grid = QtGui.QGridLayout()
grid.addWidget(self.dateLabel, 0, 0)
grid.addWidget(self.pushButton, 0, 1)
widget.setLayout(grid)
self.pushButton.clicked.connect(self.closeEvent)
def closeEvent(self, event):
QtGui.QApplication.quit()
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
window = MyApp()
window.show()
sys.exit(app.exec_())
This will get the controls on the screen, although the layout leaves a lot to be desired. You may have to make modifications to this based on what's in your .ui file. One thing that you'll want to note in this example is that the QMainWindow needs a central widget (widget in the example above). You then set the layout on that widget.

You can use the designer to create your .ui file
The you can load it in your .py using something like:
from PyQt4 import QtCore, QtGui, uic
class my_win(QtGui.QMainWindow):
def __init__(self):
self.ui = uic.loadUi('my_ui.ui',self)
then you can access all your widgets with something like
self.ui.actionQuit.triggered.connect(QtGui.qApp.quit)
or
self.ui.my_button.triggered.connect(self.do_someting)

Thanks to JCVanHamme (the programLauncher.ui hint) and also outside help I now learned most of what I need to know to access MainWindow at run time. So for anyone interested in this beginner tip:
Take a blank form in QT Designer
Add a control
Run pyuic4 batch file
Take a look at the generated .py file to learn EVERYTHING about how to add controls.
Don't let the power go to your head - cheers

PyQt: How can I get a large list of filenames from the user?

The FileDialog in pyqt is an excellent way to get one path for a file from the user, but is there a good way to get a large number of file selections from the user?

Use QFileDialog.getOpenFileNames to allow the user to select multiple files:
from PyQt4 import QtGui, QtCore
class Window(QtGui.QWidget):
def __init__(self):
QtGui.QWidget.__init__(self)
layout = QtGui.QVBoxLayout(self)
self.button = QtGui.QPushButton('Select Files', self)
layout.addWidget(self.button)
self.button.clicked.connect(self.handleButton)
def handleButton(self):
title = self.button.text()
for path in QtGui.QFileDialog.getOpenFileNames(self, title):
print path
if __name__ == '__main__':
import sys
app = QtGui.QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())

I would suggest you to let the user use drag & drop to add files directly from their favorite file browser. As I did this in wxpython without any trouble and user-feedbacks are pretty good :)