I have just designed my application inside pyQt Designer 5, generated my main.ui to main.py and my assets.qrc to assets_rc.py. No errors, when I now run main.py from my terminal nothing happends. Have I missed a step? Am I supposed to edit my main.py file now?
Cheers!
Python 3.3.0
pyQT 5
This is for PyQt4, but should be the same for PyQt5.
Let's say your ui is called "mainwindow.ui". Compile this with pyuic4 into "mainWindowUi.py" (or whatever, just stick to the name).
Now create a file "mainWindow.py" with more or less this content:
from PyQt4 import QtGui
from mainWindowUi import Ui_MainWindow #same name as appears in mainWindowUi.py
class MainWindow (QtGui.QMainWindow): #Or wherever you are inheriting from
def __init__ (self, parent = None):
super (MainWindow, self).__init__ ()
self.ui = Ui_MainWindow () #same name as appears in mainWindowUi.py
self.ui.setupUi (self)
#implement slots and signals and other funny things
Now create a file "program.py" with more or less this content:
#! /usr/bin/python3.3
import sys
from PyQt4 import QtGui
from mainWindow import MainWindow
def main():
app = QtGui.QApplication (sys.argv)
m = MainWindow ()
m.show ()
sys.exit (app.exec_ () )
if __name__ == '__main__':
main ()
Run the program.py file. This is more or less the skeleton of a Qt application.
Related
I have a fresh QtCreator installation, and I set it up to run using a fresh install of Python3.8 on which I pip-installed both pyside2 and pyside6.
When I create a new Qt for Python - Window (UI file) application, whatever I do to the UI file the window always shows up empty and with the default size when I run the app.
I've tried with a QDialog, QMainApplication, using Pyside2 or Pyside6, I've checked that it was correctly loading the UI (and the right one) - no dice. It just won't update, and appears not to have any reason not to.
Default code for completeness:
# This Python file uses the following encoding: utf-8
import os
from pathlib import Path
import sys
from PySide2.QtWidgets import QApplication, QDialog
from PySide2.QtCore import QFile
from PySide2.QtUiTools import QUiLoader
class Dialog(QDialog):
def __init__(self):
super(Dialog, self).__init__()
self.load_ui()
def load_ui(self):
loader = QUiLoader()
path = os.fspath(Path(__file__).resolve().parent / "form.ui")
ui_file = QFile(path)
ui_file.open(QFile.ReadOnly)
loader.load(ui_file, self)
ui_file.close()
if __name__ == "__main__":
app = QApplication([])
widget = Dialog()
widget.show()
sys.exit(app.exec_())
(In the UI I just drag-dropped a button right in the middle and saved the file)
Am I forgetting something fundamental? I'm only used to programming in C++ using QtCreator.
I was expecting this to work right out of the box, but it's not.
This only dynamically load the UI as a new widget, with this custom class as a parent.
If I want signals and slots to work, the only thing I've found was to add a custom build step:
Command: <path to pyside6 install, use pip show to know where>\uic.exe
Arguments: <filename of the .ui file> -o <the python translation .py
which will serve as baseclass> -g python
Working directory: [your project dir]
Then signals and slots need to be connected manually, so QtCreator really only enables you to draw the user interface but all the logic still needs to be done by hand. Component variables are normally named after their UI name, but you can see for yourself in the baseclass file. This is a big step back from how QtCreator is used in C++ ("go to slot" will not work).
Code to use:
import sys
from PySide6.QtWidgets import QApplication, QMainWindow
from PySide6.QtCore import QFile
from PySide6.QtUiTools import QUiLoader
from YourGenPyFileName import Ui_YourUIName
class MainWindow(QMainWindow, Ui_YourUIName):
def __init__(self):
super(MainWindow, self).__init__()
self.setupUi(self)
if __name__ == "__main__":
app = QApplication([])
widget = MainWindow()
widget.show()
sys.exit(app.exec_())
First File first.py
import pyqt5py
ret=pyqt5py.confirm()
print(ret)
Second File Having PYQT5 name: pyqt5py.py
import sys
from PyQt5 import QtWidgets, uic
class Ui(QtWidgets.QDialog):
def __init__(self,button1='Ok',button2='Cancel',text='Are You Sure?'):
super(Ui, self).__init__() # Call the inherited classes __init__ method
uic.loadUi('dialog.ui', self) # Load the .ui file
# Show the GUI
self.pushButton1.clicked.connect(lambda: self.click(1))
self.pushButton2.clicked.connect(lambda: self.click(2))
self.label.setText(text)
self.pushButton1.setText(button1)
self.pushButton2.setText(button2)
self.show()
def click(self,args):
print(self)
return self.sender().text()
app = QtWidgets.QApplication(sys.argv) # Create an instance of QtWidgets.QApplication
def confirm():
def pressed():
return 'clicked'
window = Ui(button1='Ok',button2='Cancel',text='Are You Sure?') # Create an instance of our class
print(window)
window.pushButton1.clicked.connect(pressed)
app.exec_() # Start the application
but i dont know what changes should i do make my first.py to work,i have correctly made the pyqt5 file but i dont know how to add def to call it for confirm
#######################
I Updated My Second File
As suggested by bfris you should rewrite the last lines of pyqt5py.py as follows:
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
window = Ui(button1='Ok',button2='Cancel',text='Are You Sure?')
app.exec_()
That way you can run this file directly for debbugging purposes, but also import it elsewhere.
To use your widget in first.py you need to create an instance of it there.
first.py:
from pyqt5py.py import UI
app = QtWidgets.QApplication(sys.argv)
window = Ui(button1='Ok',button2='Cancel',text='Are You Sure?')
app.exec_()
Usually I use a QDialog within a Qt environment where it is opened from a QMainWindow and also returning which button was clicked to the QMainWindow.
However as I understand you would like to run another program and in between open your UI? I am not experienced doing that but it seems to me that its exec method does exactly that though you should read this discussion about a bug related to it.
Alternatively in first.py you connect the pushbutton's clicked signal to a slot, a function there.
I've created many GUI interfaces in PyQT using QT Designer, but now I'm trying to open an interface from another one, and I don't know how to do it..
Start.py is the file which run the GUI Interface Authentification_1 and Acceuil_start.py is the file which run the GUI interface Acceuil_2.py, now I want from Start.py to lunch Acceuil_start.py.
Do you have any idea about that ? Thank you.
Here's my code :
Start.py :
import sys
from PyQt4 import QtCore, QtGui
from Authentification_1 import Ui_Fenetre_auth
from Acceuil_2 import Ui_MainWindow #??? Acceuil_2.py is the file which I want to open
class StartQT4(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
self.ui = Ui_Fenetre_auth()
self.ui.setupUi(self)
def authentifier(val): #Slot method
self.Acceuil = Acceuil() #???
self.Acceuil.show() #???
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
myapp = StartQT4()
myapp.show()
sys.exit(app.exec_())
Acceuil_start.py
import sys
from PyQt4 import QtCore, QtGui
from Authentification_1 import Ui_Fenetre_auth
from Acceuil_2 import Ui_MainWindow
class StartQT4(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
myapp = StartQT4()
myapp.show()
sys.exit(app.exec_())
First, you should to name your GUI classes so they have a different name, and not the generic one, so you could distinct them.
Why you would need to do that? Well - simply, because it makes sense - if every class is representing different type of dialog, so it is the different type - and it should be named differently. Some of the names are/may be: QMessageBox, AboutBox, AddUserDialog, and so on.
In Acceuil_start.py (you should rename class in other module, too).
import sys
from PyQt4 import QtCore, QtGui
from Authentification_1 import Ui_Fenetre_auth
from Acceuil_2 import Ui_MainWindow
class Acceuil(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
myapp = Acceuil()
myapp.show()
sys.exit(app.exec_())
in the parent class, when you want to create the window, you are close (but it should work in any case):
def authentifier(val): #Slot method
self.Acceuil = Acceuil(self) # You should always pass the parent to the child control
self.Acceuil.show() #???
About parent issue: If your widget/window is creating another widget, setting creator object to be parent is always a good idea (apart from some singular cases), and you should read this to see why is that so:
QObjects organize themselves in object trees. When you create a QObject with another object as parent, it's added to the parent's children() list, and is deleted when the parent is. It turns out that this approach fits the needs of GUI objects very well. For example, a QShortcut (keyboard shortcut) is a child of the relevant window, so when the user closes that window, the shorcut is deleted too.
Edit - Minimal Working Sample
To see what I am trying to tell you, I've built a simple example. You have two classes - MainWindow and
ChildWindow. Every class can work without other class by creating separate QApplication objects. But, if you import ChildWindow in MainWindow, you will create ChildWindow in slot connected to singleshot timer which will trigger in 5 seconds.
MainWindow.py:
import sys
from PyQt4 import QtCore, QtGui
from ChildWindow import ChildWindow
class MainWindow(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
QtCore.QTimer.singleShot(5000, self.showChildWindow)
def showChildWindow(self):
self.child_win = ChildWindow(self)
self.child_win.show()
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
myapp = MainWindow()
myapp.show()
sys.exit(app.exec_())
ChildWindow.py:
import sys
from PyQt4 import QtCore, QtGui
class ChildWindow(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
self.setWindowTitle("Child Window!")
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
myapp = ChildWindow()
myapp.show()
sys.exit(app.exec_())
To reference the other dialog from Start.py, you must prefix it by the module name, which in this case is Acceuil_start. As such, it is OK if there are duplicated function names in each module. So, you would have:
def authentifier(val): #Slot method
dlg = Acceuil_start.StartQT4()
dlg.exec_()
However, if you want these to run from the same process, keep in mind that you can't have two app objects. You would probably want to structure Acceuil_start.py to act like a dialog, rather than a main window. If these are two distinct main windows, you might find it easier to just invoke another Python interpreter with the Acceuil_start.py as a parameter.
I am working on pyqt4 and python26 application.I created forms using qt designer (.ui files).
I converted them to .py and .pyc files.But when i try to run .py file ,python command line comes and goes within a second,the form (corresponding .ui file) cannot be seen...what can be the problem??
this is my code:(.py file)
from DlgAbout_ui import Ui_DlgAbout
from PyQt4.QtCore import *
from PyQt4.QtGui import *
import resources
class DlgAbout(QDialog, Ui_DlgAbout):
def __init__(self, parent=None):
QDialog.__init__(self, parent)
self.setupUi(self)
self.logo.setPixmap( QPixmap( ":/icons/faunalia_logo.png" ) )
text = self.txt.toHtml()
text = text.replace( "$PLUGIN_NAME$", "RT Sql Layer" )
self.txt.setHtml(text)
First, don't use:
from PyQt4.QtCore import *
from PyQt4.QtGui import *
Instead:
from PyQt4 import QtCore, QtGui
And reference the modules explicitly.
class DlgAbout(QtGui.QDialog, Ui_DlgAbout):
etc.
In your code, all you've done is defined a dialog box. You haven't defined any main application to run, or any way to show the dialog box.
For an example, here's a basic main application to run:
from PyQt4 import QtGui
import sys
class MyMainWindow(QtGui.QMainWindow):
def __init__(self, parent=None):
super(MyMainWindow, self).__init__(parent)
self.form_widget = FormWidget(self)
self.setCentralWidget(self.form_widget)
class FormWidget(QtGui.QWidget):
def __init__(self, parent):
super(FormWidget, self).__init__(parent)
self.layout = QtGui.QVBoxLayout(self)
self.button = QtGui.QPushButton("Button!")
self.layout.addWidget(self.button)
if __name__ == "__main__":
app = QtGui.QApplication([])
foo = MyMainWindow()
foo.show()
sys.exit(app.exec_())
This defines a main window, and a form (Which MyMainWindow sets up, as you can see).
I then check if this is the main file being run (if __name__ == "__main__":), and I start the application (The app = QtGui.QApplication([]), create the main window, and show the main window.
In your case, you could define a main application like I did, and make it alert your QDialog.
Your python code just imports some modules and then defines a new class. It doesn't do anything with the class it has defined, though. In other words, once Python is done creating the new class, it is finished, and it exits.
I don't know PyQT at all, but most likely you need to start the GUI's main loop, and also instantiate an instance of your new class and pass it to PyQT.
I am looking for a simple example of how to directly load a QtDesigner generated .ui file into a Python application.
I simply would like to avoid using pyuic4.
For the complete noobs at PySide and .ui files, here is a complete example:
from PySide import QtCore, QtGui, QtUiTools
def loadUiWidget(uifilename, parent=None):
loader = QtUiTools.QUiLoader()
uifile = QtCore.QFile(uifilename)
uifile.open(QtCore.QFile.ReadOnly)
ui = loader.load(uifile, parent)
uifile.close()
return ui
if __name__ == "__main__":
import sys
app = QtGui.QApplication(sys.argv)
MainWindow = loadUiWidget(":/forms/myform.ui")
MainWindow.show()
sys.exit(app.exec_())
PySide, unlike PyQt, has implemented the QUiLoader class to directly read in .ui files.
From the linked documentation,
loader = QUiLoader()
file = QFile(":/forms/myform.ui")
file.open(QFile.ReadOnly)
myWidget = loader.load(file, self)
file.close()
Another variant, based on a shorter load directive, found on https://askubuntu.com/questions/140740/should-i-use-pyqt-or-pyside-for-a-new-qt-project#comment248297_141641. (Basically, you can avoid all that file opening and closing.)
import sys
from PySide import QtUiTools
from PySide.QtGui import *
app = QApplication(sys.argv)
window = QtUiTools.QUiLoader().load("filename.ui")
window.show()
sys.exit(app.exec_())
Notes:
filename.ui should be in the same folder as your .py file.
You may want to use if __name__ == "__main__": as outlined in BarryPye's answer
Here is some example for PySide6 and Windows. (For linux you need use /, not \\)
from PySide6.QtUiTools import QUiLoader
from PySide6.QtCore import QFile
from PySide6.QtWidgets import QApplication
import sys
if __name__ == "__main__":
app = QApplication(sys.argv)
loader = QUiLoader()
file = QFile("gui.ui")
file.open(QFile.ReadOnly)
ui = loader.load(file)
file.close()
ui.show()
sys.exit(app.exec_())
For people coming from PyQt5/6 who are thoroughly confused by this:
PySide does not have the same functionality that we're used to, which is to load the ui file at the top of the window/widget subclass like so:
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, *args, **kwargs):
super(MainWindow, self).__init__(*args, **kwargs)
'''Load ui'''
uic.loadUi("mainwindow.ui", self)
There is nothing very similar to this in PySide.
Instead, the best thing to do is embrace the ui-file compilation that you've avoided because loading the ui file is so easy in PyQt. This has a couple of advantages
There is a performance advantage - the ui file does not need to be compiled at run time
You get type hints for all your widgets without needing to manually add them
The disadvantage is that you have to use pyside6-uic to compile the *.ui files each time you edit them, but this can be made less painful by using scripts to automate the process - either setting it up in VSCode, a batch file or a powershell script. After you've done this, the code is nice:
#ui_mainwindow is the ui_mainwindow.py file
#Ui_MainWindow is the class that was produced within that .py file
from ui_mainwindow import Ui_MainWindow
class MainWindow(QtWidgets.QMainWindow, Ui_MainWindow):
def __init__(self):
super(MainWindow, self).__init__()
'''Load the ui'''
self.setupUi(self)