PyQt and QtDesigner - pyqt4

I am trying to implement a LED in PyQt named disLDR1 by trying to change the background color. I am trying to use QPalette to change the BackgroundRole. But what is the equivalent of Qt::red?
Is this the correct way to set the background color or is there any other way?
#!/usr/bin/python -d
import sys
from PyQt4 import QtCore, QtGui
from main import Ui_Form
from PyQt4.QtGui import QPalette
class Top(QtGui.QMainWindow):
def __init__(self, parent = None):
QtGui.QWidget.__init__(self, parent)
self.ui = Ui_Form()
self.ui.setupUi(self)
for i in 1, 10:
self.setOff()
self.setOn()
def setOff(self):
self.pal = QPalette(self.ui.disLDR1.palette())
self.pal.setColor(self.ui.disLDR1.backgroundRole(), <<<RED COLOR>>>)
self.ui.disLDR1.setPalette(pal)
def setOn(self):
self.pal = QPalette(self.ui.disLDR1.palette())
self.pal.setColor(self.ui.disLDR1.backgroundRole(), <<<GREEN COLOR>>>)
self.ui.disLDR1.setPalette(pal)
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
myapp = Top()
myapp.show()
sys.exit(app.exec_())
EDIT: I have been trying to take help from In Qt, how do I set the background color of a widget like combobox or double spin box? but don't know what to substitute for QT::red

You can find the list of predefined Qt color objects at this link. In this case you would just need to use QtCore.Qt.red and QtCore.Qt.blue. You could also use the QColor class to generate arbitrary colors.
It's a matter of preference, but I personally think the easiest and most powerful way to go would be to use a style sheet.

Related

How to translate ui file + several questions [duplicate]

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)

Start the script in PyQt5 and python3 [duplicate]

I have created a form using PyQt4 which has a push button. On this push button I want to call another python script which looks like this:
File1.py:
import sys
from PyQt4 import QtCore, QtGui
from file1_ui import Ui_Form
class MyForm(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
self.ui = Ui_Form()
self.ui.setupUi(self)
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
myapp = MyForm()
myapp.show()
sys.exit(app.exec_())
File1_ui.py
from PyQt4 import QtCore, QtGui
try:
_fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
_fromUtf8 = lambda s: s
class Ui_Form(object):
def setupUi(self, Form):
Form.setObjectName(_fromUtf8("Form"))
Form.resize(400, 300)
self.pushButton = QtGui.QPushButton(Form)
self.pushButton.setGeometry(QtCore.QRect(120, 200, 95, 20))
self.pushButton.setObjectName(_fromUtf8("pushButton"))
self.retranslateUi(Form)
QtCore.QObject.connect(self.pushButton, QtCore.SIGNAL(_fromUtf8("clicked()")), Form.close)
QtCore.QMetaObject.connectSlotsByName(Form)
def retranslateUi(self, Form):
Form.setWindowTitle(QtGui.QApplication.translate("Form", "Form", None, QtGui.QApplication.UnicodeUTF8))
self.pushButton.setText(QtGui.QApplication.translate("Form", "Close", None, QtGui.QApplication.UnicodeUTF8))
File2.py
import sys
from PyQt4 import Qt
from taurus.qt.qtgui.application import TaurusApplication
app = TaurusApplication(sys.argv)
panel = Qt.QWidget()
layout = Qt.QHBoxLayout()
panel.setLayout(layout)
from taurus.qt.qtgui.panel import TaurusForm
panel = TaurusForm()
model = [ 'test/i1/1/%s' % p for p in props ]
panel.setModel(model)
panel.show()
sys.exit(app.exec_())
File1_ui.py is created from the Qtdesigner and then I am using File1.py to execute it.So File2.py when executed alone opens up a panel and displays few attributes.I want this script to be called on the button click in the first form(file1.py) which I created using Qtdesigner.Could you let me know how I could achieve this functionality.Thanks.
You will need to make some modifications to File2.py to make the appropriate calls depending on whether it is running standalone or not. When you are launching the script via File1.py there will already be a QApplication instance with event loop running, so trying to create another and run its event loop will cause problems.
Firstly, move the core part of your script into its own function. This will allow you to easily call it from File1.py. You can then handle the case where the script is running standalone and needs to create a QApplication instance and start its event loop. (I am not familiar the the taurus library you are using, but you can probably substitute TaurusApplication for QtGui.QApplication)
File2.py:
import sys
from PyQt4 import QtCore, QtGui
def runscript():
panel = QtGui.QWidget()
layout = QtGui.QHBoxLayout(panel)
return panel # Must return reference or panel will be deleted upon return
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
panel = runscript()
panel.show()
sys.exit(app.exec_())
Assuming your files are in the same directory you can simply write import File2 and use File2.runscript() to run your code. You then just need to connect the function to your pushbuttons clicked() signal to run it. The only problem here is that the reference to the QWidget returned from the runscript() function will be lost (and the object deleted) if you connect directly to runscript(). For this reason I created a method launch_script() which saves a reference in MyForm.
File1.py:
import sys
from PyQt4 import QtCore, QtGui
from file1_ui import Ui_Form
import File2
class MyForm(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
self.ui = Ui_Form()
self.ui.setupUi(self)
# This is a bit of a hack.
self.ui.pushButton.clicked.connect(self.launch_script)
def launch_script(self):
self.panel = File2.runscript()
self.panel.show()
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
myapp = MyForm()
myapp.show()
sys.exit(app.exec_())
I don't use Qt Designer, so I don't know the correct way to go about connecting the signal to launch_script(). The code I have written should work, but obviously violates OOP principles and is dependent on the name of the pushbutton widget assigned by the software.

Why doesn't this custom QWidget display correctly

I'm retrying this question with a much better code example.
The code below, in its current form, will display a green shaded QWidget in a window, which is what I want. However, when commenting out the line:
self.widget = QWidget(self.centralwidget)
and uncommenting,
self.widget = Widget_1(self.centralwidget)
the green box doesn't display. The Widget_1 class is a simple subclass of QWidget, so I'm trying to wrap my head around where the breakdown is occurring. There are no error messages, and the print("Test") line within the Widget_1 class is outputting just fine, so I know everything is being called properly.
I'm not looking to use any type of automated layouts for reasons I don't need to go into here. Can you help me to understand why the green rectangle isn't displaying, and what correction I would need to make in order to utilize the Widget_1 class?
from PyQt5.QtWidgets import QApplication, QMainWindow, QWidget
from PyQt5.QtCore import QRect
import sys
class Main_Window(object):
def setupUi(self, seating_main_window):
seating_main_window.setObjectName("seating_main_window")
seating_main_window.setEnabled(True)
seating_main_window.resize(400, 400)
self.centralwidget = QWidget(seating_main_window)
self.centralwidget.setObjectName("centralwidget")
########### The following two lines of code are causing the confusion #######
# The following line, when uncommented, creates a shaded green box in a window
self.widget = QWidget(self.centralwidget) # Working line
# The next line does NOT create the same shaded green box. Where is it breaking?
# self.widget = Widget_1(self.centralwidget) # Non-working line
self.widget.setGeometry(QRect(15, 150, 60, 75))
self.widget.setAutoFillBackground(False)
self.widget.setStyleSheet("background: rgb(170, 255, 0)")
self.widget.setObjectName("Widget1")
seating_main_window.setCentralWidget(self.centralwidget)
class Widget_1(QWidget):
def __init__(self, parent=None):
super().__init__()
self.setMinimumSize(10, 30) # I put this in thinking maybe I just couldn't see it
print("Test") # I see this output when run when Widget_1 is used above
class DemoApp(QMainWindow, Main_Window):
def __init__(self):
super().__init__()
self.setupUi(self)
if __name__ == '__main__': # if we're running file directly and not importing it
app = QApplication(sys.argv) # A new instance of QApplication
form = DemoApp() # We set the form to be our ExampleApp (design)
form.show() # Show the form
app.exec_() # run the main function
Accoriding to this Qt Wiki article:
How to Change the Background Color of QWidget
you must implement paintEvent in a custom QWidget subclass in order to use stylesheets. Also, since the widget is not part of a layout, you must give it a parent, otherwise it will not be shown. So your Widget_1 class must look like this:
from PyQt5.QtWidgets import QStyleOption, QStyle
from PyQt5.QtGui import QPainter
class Widget_1(QWidget):
def __init__(self, parent=None):
super().__init__(parent) # set the parent
print("Test")
def paintEvent(self, event):
option = QStyleOption()
option.initFrom(self)
painter = QPainter(self)
self.style().drawPrimitive(QStyle.PE_Widget, option, painter, self)
super().paintEvent(event)

one single scroll bar for two QTextEdit, pyqt4, python

How to make one single scroll bar for two QTextEdit, pyqt4, python. Or how to synchronize two scrollbars of two QTextEdit. For simultaneous scrolling texts.
Pyqt4, python.
Cross-connect the value changed signals of all the scrollbars:
from PyQt4 import QtCore, QtGui
class Window(QtGui.QWidget):
def __init__(self):
super(Window, self).__init__()
self.edit1 = QtGui.QTextEdit(self)
self.edit2 = QtGui.QTextEdit(self)
layout = QtGui.QHBoxLayout(self)
layout.addWidget(self.edit1)
layout.addWidget(self.edit2)
self.edit1.horizontalScrollBar().valueChanged.connect(
self.edit2.horizontalScrollBar().setValue)
self.edit1.verticalScrollBar().valueChanged.connect(
self.edit2.verticalScrollBar().setValue)
self.edit2.horizontalScrollBar().valueChanged.connect(
self.edit1.horizontalScrollBar().setValue)
self.edit2.verticalScrollBar().valueChanged.connect(
self.edit1.verticalScrollBar().setValue)
text = '\n'.join(name for name in dir(QtCore))
self.edit1.setText(text)
self.edit2.setText(text)
if __name__ == '__main__':
import sys
app = QtGui.QApplication(sys.argv)
window = Window()
window.setGeometry(500, 300, 600, 400)
window.show()
sys.exit(app.exec_())

how to approach a QSpinbox in other widgets?

I'm using Qt-desiger to make a GUI.
For example I have a QSpinbox in a QCombobox in a Groubbox.
How can i use SetValue for my Spinbox?
how i have to "describe" the way to my Spinbox?
Widgets inside other Widgets do not create hierarchy in Qt, it means that if you have widget1 inside widget2 you can directly access the widget1, like self.widget1 (and self.widget2)
You can create a class which will contain all your widgets on your ui form as follows:
from PyQt4 import uic
Form, Base = uic.loadUiType(r'path\to\your\uifile.ui') #get ui Form and Base class
class Window(Form, Base):
def __init__(self, parent = None):
#here you can access your widgets
#self.combobox.addItem('Item')
#self.spinbox.setValue(10)
...
That's all you need.
You first need to use pyuic to generate a python module from the designer ui file:
pyuic4 -o mainwindow_ui.py mainwindow.ui
Then import it into your application:
from PyQt4 import QtCore, QtGui
from mainwindow_ui import Ui_MainWindow
class MainWindow(QtGui.QMainWindow, Ui_MainWindow):
def __init__(self):
super(MainWindow, self).__init__()
self.setupUi(self)
if __name__ == '__main__':
import sys
app = QtGui.QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
This will add all the widgets from Qt Designer, and make them attributes of the MainWindow class. The attribute names will be the same as the objectName property that was set in Qt Designer. So if the QComboBox was named "comboBox", and the QSpinBox named "spinBox", they could be accessed within the MainWindow class like this:
self.comboBox.addItems('Foo')
self.spinBox.setValue(10)

Resources