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Access A Variable from another class in PyQt5

In PyQt5, I've wrote a GUI. Basically, when a button is pressed, it open a new window, where choose an item from a list. What I want is that after you close the new window, the item you chose appears as text on the first window. It's a hard to explain.
This is the code:
import sys
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QFont
from PyQt5 import QtWidgets
from PyQt5 import QtCore
from PyQt5 import QtGui
class Add(QtWidgets.QMainWindow):
def __init__(self):
super(Add, self).__init__()
#Set The UI
self.initUI()
#Set The GUI Position And Size
self.setGeometry(1050, 500, 400, 50)
#Set The GUI Title
self.setWindowTitle("Add")
def initUI(self):
Central = QtWidgets.QWidget(self)
self.setCentralWidget(Central)
self.deckButton = QtWidgets.QPushButton(self)
self.deckButton.setText("Choose")
self.deckButton.clicked.connect(self.open_deck_browser)
hbox = QtWidgets.QHBoxLayout()
hbox.addWidget(self.deckButton, 1)
Central.setLayout(hbox)
def open_deck_browser(self):
self.w = SetDeck()
self.w.show()
class SetDeck(QtWidgets.QMainWindow):
def __init__(self):
super(SetDeck, self).__init__()
#Set The UI
self.initUI()
#Set The GUI Position And Size
self.setGeometry(200, 200, 800, 640)
#Set The GUI Title
self.setWindowTitle("Choose Deck")
def initUI(self):
widAddToDeckWindow = QtWidgets.QWidget(self)
self.setCentralWidget(widAddToDeckWindow)
#Create The List Widget
self.deckList = QtWidgets.QListWidget()
self.deckList.insertItem(0, "Hello")
self.deckList.insertItem(1, "Hi")
self.deckList.insertItem(2, "Hello There")
self.deckList.item(0).setSelected(True)
self.deckList.itemSelectionChanged.connect(self.show_List)
print([x.row() for x in self.deckList.selectedIndexes()])
#Create The Select Deck Button
self.selectDeck = QtWidgets.QPushButton(self)
self.selectDeck.setText("Choose")
hboxCreateBottomButtons = QtWidgets.QHBoxLayout()
hboxCreateBottomButtons.addStretch()
hboxCreateBottomButtons.addWidget(self.selectDeck)
#Create The Main VBox
vboxMain = QtWidgets.QVBoxLayout()
vboxMain.addWidget(self.deckList)
vboxMain.addLayout(hboxCreateBottomButtons)
widAddToDeckWindow.setLayout(vboxMain)
def show_List(self):
print(repr(self.deckList.selectedItems()[0].text()))
def window():
app = QtWidgets.QApplication(sys.argv)
win = Add()
win.show()
sys.exit(app.exec_())
window()
I've tried using global variables, but it didn't work.

First of all, I recommend you improve your style when naming variables as they make reading easier, for example that the class name are nouns and not a verb.
Getting to the bottom of the problem, never use (or try to use) global variables as they cause silent bugs if there is a better option and you don't understand how it works. In the case that you want a window where you ask the user to provide information on how to select an option that will then be used in the main window then it is advisable to use a QDialog. In the following example, this is done and the "Choose" button is linked to the accept slot so that it closes the window, and that information can be used to know that the "x" button of the window was not closed. Also I have created a property that has the selected text.
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
class MainWindow(QtWidgets.QMainWindow):
def __init__(self):
super(MainWindow, self).__init__()
self.initUI()
self.setGeometry(1050, 500, 400, 50)
self.setWindowTitle("Add")
def initUI(self):
central = QtWidgets.QWidget(self)
self.setCentralWidget(central)
self.deckButton = QtWidgets.QPushButton()
self.deckButton.setText("Choose")
self.deckButton.clicked.connect(self.open_deck_browser)
box = QtWidgets.QVBoxLayout(central)
box.addWidget(self.deckButton)
self.label = QtWidgets.QLabel()
box.addWidget(self.label)
self.label.hide()
def open_deck_browser(self):
dialog = DeckDialog()
if dialog.exec_() == QtWidgets.QDialog.Accepted:
self.label.show()
self.label.setText(dialog.selected_text)
class DeckDialog(QtWidgets.QDialog):
def __init__(self):
super(DeckDialog, self).__init__()
self.initUI()
self.setGeometry(200, 200, 800, 640)
self.setWindowTitle("Choose Deck")
def initUI(self):
self.deckList = QtWidgets.QListWidget()
self.deckList.insertItem(0, "Hello")
self.deckList.insertItem(1, "Hi")
self.deckList.insertItem(2, "Hello There")
self.deckList.item(0).setSelected(True)
self.selectDeck = QtWidgets.QPushButton(self)
self.selectDeck.setText("Choose")
hboxCreateBottomButtons = QtWidgets.QHBoxLayout()
hboxCreateBottomButtons.addStretch()
hboxCreateBottomButtons.addWidget(self.selectDeck)
vboxMain = QtWidgets.QVBoxLayout(self)
vboxMain.addWidget(self.deckList)
vboxMain.addLayout(hboxCreateBottomButtons)
self.selectDeck.clicked.connect(self.accept)
#property
def selected_text(self):
items = self.deckList.selectedItems()
if items:
return items[0].text()
return ""
def main():
app = QtWidgets.QApplication(sys.argv)
win = MainWindow()
win.show()
sys.exit(app.exec_())
if __name__ == "__main__":
main()

Vertical Layout not showing widgets [duplicate]

I am making a GUI with PyQt, and I am having issues with my MainWindow class. The window doesn't show widgets that I define in other classes, or it will show a small portion of the widgets in the top left corner, then cut off the rest of the widget.
Can someone please help me with this issue?
Here is some example code showing my issue.
import sys
from PyQt4 import QtGui, QtCore
class MainWindow(QtGui.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent=parent)
self.resize(300, 400)
self.centralWidget = QtGui.QWidget(self)
self.hbox = QtGui.QHBoxLayout(self.centralWidget)
self.setLayout(self.hbox)
names = ['button1', 'button2', 'button3']
testButtons = buttonFactory(names, parent=self)
self.hbox.addWidget(testButtons)
class buttonFactory(QtGui.QWidget):
def __init__(self, names, parent=None):
super(buttonFactory, self).__init__(parent=parent)
self.vbox = QtGui.QVBoxLayout()
self.setLayout(self.vbox)
for name in names:
btn = QtGui.QPushButton(name)
self.vbox.addWidget(btn)
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
gui = MainWindow()
gui.show()
app.exec_()

A QMainWindow has a central widget that is a container in which you should add your widgets. It has its own layout. The layout of the QMainWindow is for toolbars and such. The centralWidget must be set with the setCentralWidget method. It isn't enough to just call it self.centralWidget
Use the following three lines instead.
self.setCentralWidget(QtGui.QWidget(self))
self.hbox = QtGui.QHBoxLayout()
self.centralWidget().setLayout(self.hbox)

Pyside2 how to open the dialog but not always on top

I create a main frame and a pushbutton ,
and let button clicked to open a dialog , but the dialog always on top ,
I try to used setWindowsFlag but not work.
from PySide2.QtWidgets import QApplication,QMainWindow,QTabWidget,QWidget
from PySide2.QtWidgets import QMessageBox,QFileDialog,QErrorMessage
from PySide2 import QtCore, QtGui, QtWidgets
class UI_Test20(object):
def setupUi(self, Test202):
Test202.setObjectName("Test202")
Test202.resize(100,100)
self.centralwidget = QtWidgets.QWidget(Test202)
self.centralwidget.setObjectName("centralwidget")
self.pb = QtWidgets.QPushButton(self.centralwidget)
self.pb.setText('push button!')
Test202.setCentralWidget(self.centralwidget)
self.pb.clicked.connect(self.btnClicked)
self.retranslateUi(Test202)
QtCore.QMetaObject.connectSlotsByName(Test202)
def retranslateUi(self, Test202):
Test202.setWindowTitle(QtWidgets.QApplication.translate("Test202", "MainWindow", None, -1))
def btnClicked(self):
ui = Ui_Dialog1(self)
ui.show()
class Test20(QMainWindow, UI_Test20) :
def __init__(self, parent):
super(Test20, self).__init__(parent)
self.setupUi(self)
and the dialog code
class Ui_Dialog1(QtWidgets.QDialog):
def __init__(self, parent=None):
super(Ui_Dialog1, self).__init__(parent)
self.p = parent
self.setupUi(self)
def setupUi(self, Dialog1):
Dialog1.setObjectName("Dialog1")
Dialog1.resize(333, 173)
main
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
ui = Test20(None)
ui.show()
sys.exit(app.exec_())

The problem is caused by the fact that the main window is the parent of the QDialog, so it must be removed, but if that is done, the garbage collector will delete it, so the QDialog member of the class must be made:
def btnClicked(self):
self.ui = Ui_Dialog1()
self.ui.show()
Plus: the correct thing is not to modify the design so I move the connection and the slot associated with the clicked button pb and if we want it to close when the window closes we overwrite the closeEvent() method:
class Test20(QMainWindow, UI_Test20):
def __init__(self, parent):
super(Test20, self).__init__(parent)
self.setupUi(self)
self.pb.clicked.connect(self.btnClicked)
def btnClicked(self):
self.ui = Ui_Dialog1()
self.ui.show()
def closeEvent(self, *args, **kwargs):
self.ui.close()
QMainWindow.closeEvent(self, *args, **kwargs)

Clear QLineEdit on click event

I am using the given code, I want the user to enter text in the QLineEdit widget, press the Copy! button and see the inputted text replace the 'N/A' label. My questions is: following this procedure, how can I clear the text inputted in the QLineEdit widget with a simple mouse click?
From what I read (this, this and this) it seems like I need to reimplement focusInEvent() in a new class extending QLineEdit. My problem is that the code for my GUI has been imported from Qt Designer using pyuic5 and the examples cited above don't seem to take this in consideration.
Here is my code:
from PyQt5.QtWidgets import *
import sys
import QLineEdit_test
class MainWindow(QMainWindow, QLineEdit_test.Ui_QLineEdit_test):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.setupUi(self)
self.copy_button.clicked.connect(self.copy_and_print)
def copy_and_print(self):
self.label.setText(self.lineEdit.text())
def main():
app = QApplication(sys.argv)
form = MainWindow()
form.show()
app.exec_()
if __name__ == "__main__":
main()
Here is my converted .ui file:
from PyQt5 import QtCore, QtGui, QtWidgets
class Ui_QLineEdit_test(object):
def setupUi(self, QLineEdit_test):
QLineEdit_test.setObjectName("QLineEdit_test")
QLineEdit_test.resize(300, 200)
QLineEdit_test.setMaximumSize(QtCore.QSize(300, 200))
self.centralwidget = QtWidgets.QWidget(QLineEdit_test)
self.centralwidget.setObjectName("centralwidget")
self.gridLayout_2 = QtWidgets.QGridLayout(self.centralwidget)
self.gridLayout_2.setObjectName("gridLayout_2")
self.gridLayout = QtWidgets.QGridLayout()
self.gridLayout.setObjectName("gridLayout")
self.lineEdit = QtWidgets.QLineEdit(self.centralwidget)
self.lineEdit.setMaximumSize(QtCore.QSize(120, 16777215))
self.lineEdit.setObjectName("lineEdit")
self.gridLayout.addWidget(self.lineEdit, 0, 0, 1, 1)
self.copy_button = QtWidgets.QPushButton(self.centralwidget)
self.copy_button.setObjectName("copy_button")
self.gridLayout.addWidget(self.copy_button, 1, 0, 1, 1)
self.label = QtWidgets.QLabel(self.centralwidget)
self.label.setMaximumSize(QtCore.QSize(200, 20))
self.label.setAlignment(QtCore.Qt.AlignCenter)
self.label.setObjectName("label")
self.gridLayout.addWidget(self.label, 2, 0, 1, 1)
self.gridLayout_2.addLayout(self.gridLayout, 0, 0, 1, 1)
QLineEdit_test.setCentralWidget(self.centralwidget)
self.menubar = QtWidgets.QMenuBar(QLineEdit_test)
self.menubar.setGeometry(QtCore.QRect(0, 0, 300, 22))
self.menubar.setObjectName("menubar")
QLineEdit_test.setMenuBar(self.menubar)
self.statusbar = QtWidgets.QStatusBar(QLineEdit_test)
self.statusbar.setObjectName("statusbar")
QLineEdit_test.setStatusBar(self.statusbar)
self.retranslateUi(QLineEdit_test)
QtCore.QMetaObject.connectSlotsByName(QLineEdit_test)
def retranslateUi(self, QLineEdit_test):
_translate = QtCore.QCoreApplication.translate
QLineEdit_test.setWindowTitle(_translate("QLineEdit_test", "MainWindow"))
self.copy_button.setText(_translate("QLineEdit_test", "Copy!"))
self.copy_button.setShortcut(_translate("QLineEdit_test", "Return"))
self.label.setText(_translate("QLineEdit_test", "N/A"))

The solution is to promote QtDesigner use our custom QLineEdit where we implement the signal clicked with the help of mousePressEvent, this class will be called ClickableLineEdit and the file will be called ClickableLineEdit.py.
ClickableLineEdit.py
from PyQt5.QtCore import pyqtSignal
from PyQt5.QtWidgets import QLineEdit
class ClickableLineEdit(QLineEdit):
clicked = pyqtSignal()
def mousePressEvent(self, event):
self.clicked.emit()
QLineEdit.mousePressEvent(self, event)
To promote it, the following structure will be considered:
.
├── ClickableLineEdit.py
├── main.py
├── your.ui
└── QLineEdit_test.py
Open the design with Qt Designer and right click on the QLineEdit and select Promote to ...:
A menu will open and place the following
then press and Promote. Then we generate the code again.
Then we connect the signal to clear:
class MainWindow(QMainWindow, QLineEdit_test.Ui_QLineEdit_test):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.setupUi(self)
self.copy_button.clicked.connect(self.copy_and_print)
self.lineEdit.clicked.connect(self.lineEdit.clear)
def copy_and_print(self):
self.label.setText(self.lineEdit.text())
Update:
PySide2:
from PySide2 import QtCore, QtWidgets
class ClickableLineEdit(QtWidgets.QLineEdit):
clicked = QtCore.Signal()
def mousePressEvent(self, event):
super(ClickableLineEdit, self).mousePressEvent(event)
self.clicked.emit()
class App(QtWidgets.QWidget):
def __init__(self):
super().__init__()
self.lineedit = ClickableLineEdit()
self.lineedit.clicked.connect(self.lineedit.clear)
lay = QtWidgets.QVBoxLayout(self)
lay.addWidget(self.lineedit)
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication.instance()
if app is None:
app = QtWidgets.QApplication(sys.argv)
ex = App()
ex.show()
sys.exit(app.exec_())

def __init__(self, *args, **kwargs):
QWidget.__init__(self, *args, **kwargs)
layout = QGridLayout()
self.setLayout(layout)
self.lineedit = QLineEdit()
self.lineedit.returnPressed.connect(self.press)
layout.addWidget(self.lineedit, 0, 0)
def press(self):
print("Hi World")
self.lineedit.clear()

If someone is still looking for a way to do this, but you only want the Line edit to be cleared when it first clicked and not every time it is clicked, you can do so without using variables like this :
def init_UI(self):
self.text_input = QLineEdit('Type your name')
self.text_input.mousePressEvent = self._mousePressEvent
def _mousePressEvent(self, event):
self.text_input.clear()
self.text_input.mousePressEvent = None
This way the _mousePressEvent gets called only once

I have an optional solution in one line:
self.lineEdit.mouseReleaseEvent = self.copy_and_print
Make sure you are receiving two parameters in your function (self,event)
I hope I helped you
Full post: https://wiki.python.org/moin/PyQt/Making%20non-clickable%20widgets%20clickable

Use mousePressEvent of QLineEdit to detect mouse click. To clear the text use clear() method or setText() method of QLineEdit.
#called when ever mouse is pressed
def mousePressed(self, event):
print('mouse pressed')
self.lineEdit=QLineEdit("Awesome day")#from PyQt5.QtWidget import QLineEdit
self.lineEdit.mousePressEvent = self.mousePressed
Example program :
import sys
from PyQt5.QtWidgets import QWidget, QVBoxLayout, QHBoxLayout, QPushButton, QApplication, QLineEdit
class ButtonPanel(QWidget):
def __init__(self, heading):
self.initUI(heading)
def initUI(self, heading):
super().__init__()
self.layout = QHBoxLayout()
self.lineEdit = QLineEdit(heading)
#self.lineEdit.setReadOnly(True)
self.lineEdit.returnPressed.connect(self.returnPressed)
self.lineEdit.mousePressEvent = self.mousePressed
self.delete = QPushButton("D")
self.layout.addWidget(self.lineEdit)
self.layout.addWidget(self.delete)
self.setLayout(self.layout)
self.show()
#called when mouse is clicked
def mousePressed(self, event):
self.lineEdit.clear() #text is cleared
//self.lineEdit.setText("") #this way we can also clear the text
print('mouse pressed')
//called when return key is pressed
def returnPressed(self):
print('return pressed')
if __name__ == "__main__":
app = QApplication(sys.argv)
b = ButtonPanel("Awesome")
sys.exit(app.exec())
Output :

PyQt4: Create a custom dialog that returns parameters

I'm attempting to add a custom dialog box to my current GUI that can be launched for the user to set some parameters. Ideally, I would like to create the custom dialog using QtDesigner. Below is the code generated by pyuic4 from the QtDesigner ui code for the dialog box.
from PyQt4 import QtCore, QtGui
class Ui_Dialog(object):
def setupUi(self, Dialog):
Dialog.setObjectName("Dialog")
Dialog.resize(508, 300)
self.buttonBox = QtGui.QDialogButtonBox(Dialog)
self.buttonBox.setGeometry(QtCore.QRect(150, 250, 341, 32))
self.buttonBox.setOrientation(QtCore.Qt.Horizontal)
self.buttonBox.setStandardButtons(QtGui.QDialogButtonBox.Cancel|QtGui.QDialogButtonBox.Ok)
self.buttonBox.setObjectName("buttonBox")
self.label = QtGui.QLabel(Dialog)
self.label.setGeometry(QtCore.QRect(10, 120, 181, 31))
font = QtGui.QFont()
font.setPointSize(16)
self.label.setFont(font)
self.label.setObjectName("label")
self.sl_value = QtGui.QSlider(Dialog)
self.sl_value.setGeometry(QtCore.QRect(220, 120, 161, 31))
self.sl_value.setOrientation(QtCore.Qt.Horizontal)
self.sl_value.setObjectName("sl_value")
self.ed_value = QtGui.QLineEdit(Dialog)
self.ed_value.setGeometry(QtCore.QRect(400, 120, 41, 31))
font = QtGui.QFont()
font.setPointSize(16)
self.ed_value.setFont(font)
self.ed_value.setObjectName("ed_value")
self.retranslateUi(Dialog)
QtCore.QObject.connect(self.buttonBox, QtCore.SIGNAL("accepted()"), Dialog.accept)
QtCore.QObject.connect(self.buttonBox, QtCore.SIGNAL("rejected()"), Dialog.reject)
QtCore.QMetaObject.connectSlotsByName(Dialog)
def retranslateUi(self, Dialog):
Dialog.setWindowTitle(QtGui.QApplication.translate("Dialog", "Dialog", None, QtGui.QApplication.UnicodeUTF8))
self.label.setText(QtGui.QApplication.translate("Dialog", "Set example value:", None, QtGui.QApplication.UnicodeUTF8))
This is saved in Sub2.py
Then, in my main python file, I add
from Sub2 import Ui_Dialog
I create a new class called StartSub2 with the following code
class StartSub2(QtGui.QDialog):
def __init__(self,parent=None):
QtGui.QDialog.__init__(self,parent)
self.ui = Ui_Dialog
self.ui.setupUi(self)
Then finally in inside my main GUI there's a function with the following code that should launch the dialog
def exampleSubGui(self):
dialog = StartSub2(self)
result = dialog.exec_()
Please note that the dialog is not done. Once I resolve how to even launch it I will add signal/slot connections for the slider and edit box. Also, if I understand it correctly, I need to overload the accept() method to return the user's input.
The first problem I run into is with the __init__ method of StartSub2. I get the following error:
TypeError: unbound method setupUi() must be called with Ui_Dialog instance as
first argument (got StartSub2 instance instead)
I'm attempting to take the same approach that the main GUI is taking which uses the following code
class StartQT4(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
But this does not complain about setupUi() getting a StartQT4 instance instead of a Ui_MainWindow instance. Can anyone explain the proper way to accomplish what I'm trying to do? Or can somebody point me to a clear example or reference? Please let me know if you need more information or clarification.

class StartSub2(QtGui.QDialog, Ui_Dialog):
def __init__(self,parent=None):
QtGui.QDialog.__init__(self,parent)
self.setupUi(self)
should resolve your first problem of getting the dialog to initialize.
To get info back I usually add a method called something like getValues to StartSub2, i.e.
def getValues(self):
return somethingUseful
then do
dlg = StartSub2()
if dlg.exec_():
values = dlg.getValues()
# Do stuff with values

Just wanted to provide my own answer for setting up a custom dialog with return values (not answering the code specific questions, which Whatang already did).
I found it a bit cleaner to construct a simple dialog class with a class method that can return different things as needed. I've been making these a lot lately! The idea is that the class method will construct an instance of the dialog class, and return objects out of the instance (in this case the bool ok) which is more or less a factory method (from what I understand anyway, still somewhat new to OOP).
Here's a very simplified example dialog. It should be relatively easy to extend this to whatever you need within the dialog class:
class OkDialog(QtGui.QDialog):
def __init__(self, parent):
super(OkDialog, self).__init__(parent)
self.ok = False
self.btn_ok = QtGui.QPushButton("Ok", self)
self.btn_ok.clicked.connect(self.button_press)
self.btn_cancel = QtGui.QPushButton("Cancel", self)
self.btn_cancel.clicked.connect(self.button_press)
self.btn_cancel.move(80, 0)
def button_press(self):
if self.sender() == self.btn_ok:
self.ok = True
self.close()
#classmethod
def isOkay(cls, parent):
dialog = cls(parent)
dialog.exec_()
return dialog.ok
The beauty is that when it it comes time to construct this dialog you can do it with just one line OkDialog.isOkay(parent). Putting it together into a fully working sample:
import sys
from PyQt4 import QtCore, QtGui
class OkDialog(QtGui.QDialog):
def __init__(self, parent):
super(OkDialog, self).__init__(parent)
self.ok = False
self.btn_ok = QtGui.QPushButton("Ok", self)
self.btn_ok.clicked.connect(self.button_press)
self.btn_cancel = QtGui.QPushButton("Cancel", self)
self.btn_cancel.clicked.connect(self.button_press)
self.btn_cancel.move(80, 0)
def button_press(self):
if self.sender() == self.btn_ok:
self.ok = True
self.close()
#classmethod
def isOkay(cls, parent):
dialog = cls(parent)
dialog.exec_()
return dialog.ok
class Ui_Dialog(QtGui.QDialog):
def __init__(self):
super(Ui_Dialog, self).__init__()
button = QtGui.QPushButton("Launch custom dialog", self)
button.pressed.connect(self.launch_dialog)
def launch_dialog(self):
print OkDialog.isOkay(self)
def main():
app = QtGui.QApplication(sys.argv)
ex = Ui_Dialog()
ex.show()
sys.exit(app.exec_())
if __name__ == "__main__":
main()