I would like to create a widget that has a child widget that I can dynamically change. Here is what I tried:
import sys
from PySide.QtCore import *
from PySide.QtGui import *
class Widget(QWidget):
def __init__(self, parent=None):
QWidget.__init__(self, parent)
self.setLayout(QVBoxLayout())
self.child = QLabel("foo", self)
self.layout().addWidget(self.child)
def update(self):
self.layout().removeWidget(self.child)
self.child = QLabel("bar", self)
self.layout().addWidget(self.child)
app = QApplication(sys.argv)
widget = Widget()
widget.show()
widget.update()
app.exec_()
The problem is that this doesn't actually remove the "foo" label visually. It is still rendered on top of "bar". Screenshot of the problem. How do I remove the old widget so that only the new widget is shown?
I know that I can change the text property of the label. This is not what I want in my application, I need to change the actual widget (to a different widget type).
removeWidget() only removes the item from the layout, it doesn't delete it. You can delete the child widget by calling setParent(None).
def update(self):
self.layout().removeWidget(self.child)
self.child.setParent(None)
self.child = QLabel("bar", self)
self.layout().addWidget(self.child)
Related
I have a main window created in one python module. This module also contains a class definition used to create an object called my_settings.
I also have a separate module which creates a another window (which should be in a different module for various reasons). This window allows various inputs such as opening a file and storing some settings once buttons are clicked blaa blaa.
What I want to do is then amend the attributes of my_setttings. A simplified version of the code is:
MAIN MODULE
class MainWindow(QMainWindow):
def __init__(self,parent=None):
super(MainWindow, self).__init__(parent)
QMainWindow.__init__(self)
uic.loadUi(self.some_directory + "arc_custom_main.ui", self)
self.some_button.clicked.connect(self.open_some_widget)
def open_some_widget(self):
widget = widget_in_other_module(self)
widget_in_other_module.exec_()
app = QApplication(sys.argv)
my_settings=settings()
_mainWindow = MainWindow()
_mainWindow.show()
SEPERATE MODULE
class widget_in_other_module(QDialog):
def __init__(self, parent):
my_settings.temppath = my_settings.OutputDir
QDialog.__init__(self)
self.parent = parent
my_settings.some_attribute= foo
uic.loadUi("some.ui", self)
self.pushButtonOpenMain.clicked.connect(self.openMain)
def openMain(self):
my_settings.some_other_attibute=bar
The problem I have is that I can't find a way to be able to access my_settings in the openMain method of widget_in_other_module. I'm a bit of a newbe to qt and can't for the life of me work out where I should pass my_settings. For various reasons I need all the functionality of widget_in_other_module to be outside of the main module (mostly to do with readability and future planed changes to the main module). I've tried as much as I can think of e.g. including it as a parameter in the line self.pushButtonOpenMain.clicked.connect(self.openMain,my_settings) but this doesn't seem to be allowed. Am I missing something basic here?
Instantiate settings variable in separate module and import this varable where you need it. It could be object of a class or just dictionary.
storage.py
class Settings:
def __init__(self):
print("Settings")
my_settings = Settings()
MainWindow.py
from PyQt5.QtWidgets import QMainWindow, QApplication
import sys
from Widget import Widget
from storage import my_settings
class MainWindow(QMainWindow):
def __init__(self,parent=None):
super(MainWindow, self).__init__(parent)
QMainWindow.__init__(self)
self.open_some_widget()
def open_some_widget(self):
widget = Widget()
widget.show()
widget.test()
self._widget = widget
my_settings.foo = 10
app = QApplication(sys.argv)
_mainWindow = MainWindow()
_mainWindow.show()
app.exec_()
Widget.py
from PyQt5.QtWidgets import QWidget
from storage import my_settings
class Widget(QWidget):
def test(self):
print(my_settings.foo)
Following the examples outlined in "Create simple GUI" I have tried to create Custom Widget, but nothing seems to by shown. It seems to be the simplest widget that I can imagine but still something is missing and I have no idea what.
from PyQt5.QtWidgets import *
import sys
class customWidget(QWidget):
def __init__(self, *args, **kwargs):
super(customWidget, self).__init__(*args, **kwargs)
layout = QHBoxLayout()
label = QLabel("Que chinga")
layout.addWidget(label)
class MainWindow(QMainWindow):
def __init__(self, *args, **kwargs):
super(MainWindow, self).__init__(*args, **kwargs)
self.setWindowTitle("Esta locura")
label = customWidget()
self.setCentralWidget(label)
app = QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec_()
Do any of the following in the __init__ of customWidget (they are the conceptually the same thing):
add self.setLayout(layout) after creating the layout;
change layout = QHBoxLayout() to layout = QHBoxLayout(self);
The reason is that you're not setting the layout for the widget, so the QLabel has no parent and won't be shown on its own.
In practice, the customWidget instance could know anything about those objects, so there's no reason for which it should show them.
I also suggest you to:
read about classes and instances: while it's not directly related to this issue, it has lots of aspects in common, since the parenthood relation of Qt objects (such as QWidget subclasses) is closely related to the OOP aspects of instances.
always use capitalized names for classes (CustomWidget, not customWidget), as lower cased names should only be used for variable and function names.
I want to hide a window immediately after it is created. It works only if I do this with the help of button or something.
class Example(QWidget):
def __init__(self, parent=None):
super(Example, self).__init__(parent)
self.hide() # doesn't work
self.btn = QPushButton('Hide', self)
self.btn.clicked.connect(self.click) # works
self.btn.show()
def click(self): # works
self.hide()
Apparently it seems that the code should work. What may be happening is that you are calling show() after creating the object. For example:
example = Example()
example.show()
Read this answer about hide() and show(): What's the difference in Qt between setVisible, setShown and show/hide
You can use QtCore.QTimer
class Example(QWidget):
def __init__(self, app):
QWidget.__init__(self)
QTimer.singleShot(0, self.hide)
I have a simple project with the following classes
class MainWindow(QMainWindow)
class Home(QWidget)
class Login(QWidget)
All I want is to be able to nest the QWidget classes (make them children of the QMainWindow) and display them INSIDE the MainWindow. I can't seam to figure out how to make the QWidgets "appear" after I've called them in the MainWindow.
Code is bellow:
import sys
from gui.MainWindow import Ui_MainWindow
from gui.home import Ui_Home
from gui.login import Ui_Login
from PyQt4.QtGui import QMainWindow, QApplication, QWidget
class Home(QWidget, Ui_Home):
def __init__(self):
QWidget.__init__(self)
self.setupUi(self)
class Login(QWidget, Ui_Login):
def __init__(self):
QWidget.__init__(self)
self.setupUi(self)
class MainWindow(QMainWindow,Ui_MainWindow):
def __init__(self):
QMainWindow.__init__(self)
self.setupUi(self)
#INSERT pushButton.click to go to HOME here
#INSERT pushButton.click to go to LOGIN here
def setHome(self):
self.label_Screen.setText("HOME")
self.mainwidget = Home()
#NEEDS SOMETHING HERE
def setLogin(self):
self.label_Screen.setText("LOGIN")
self.mainwidget = Login()
#NEEDS SOMETHING HERE
if __name__ == '__main__':
app = QApplication(sys.argv)
Main = MainWindow()
Main.show()
sys.exit(app.exec_())
I think I just need something where I've tagged "#NEEDS SOMETHING HERE", but I'm not sure what!
Cheers!
RESOLVED: thanks to kh25
Just had to add a layout to the QMainWindow and change the setHome to this:
def setHome(self):
self.label_Screen.setText("HOME")
self.currentScreen = Home()
self.layout.addWidget(self.currentScreen)
self.setLayout(self.layout)
The equivalent should be done for the setLogin method also.
You need to create a layout and add the widgets to this layout first. There are various types of layout. Read here:
http://doc.qt.io/qt-4.8/layout.html
For a simple case like yours I'd suggest either using a QHBoxLayout or QVBoxLayout.
Declare this layout. Call addWidget() on the layout for each of the Login and Home widgets and then call setLayout() on the QMainWindow.
I have a QStyledItemDelegate for a table. In one cell I have a QComboBox created through the delegate's createEditor. I add some items to the combobox listing via self.addItem("an item"); however, when I go into the table and actually select the items I have added, they get replaced with index values starting from 0.
How can I have the QComboBox display the actual text I added in addItem instead of the index they're getting stored in?
Here is a small standalone example of my problem:
import sys
from PySide import QtCore, QtGui, QtSql
class EditDelegate(QtGui.QStyledItemDelegate):
def __init__(self, parent=None):
super(EditDelegate, self).__init__(parent)
def createEditor(self, parent, option, index):
editor = TheEditor(parent)
return editor
class TheEditor(QtGui.QComboBox):
def __init__(self, parent=None):
super(TheEditor, self).__init__(parent)
self.addItem("Item 1")
self.addItem("Item 2")
self.addItem("Item 3")
self.setEditable(True)
class TheTable(QtGui.QTableWidget):
def __init__(self, columns, parent=None):
super(TheTable, self).__init__(parent)
self.setItemDelegate(EditDelegate())
self.setEditTriggers(QtGui.QAbstractItemView.AllEditTriggers)
self.setColumnCount(1)
self.setRowCount(1)
self.setHorizontalHeaderLabels(["QCombo"])
class MainWindow(QtGui.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.setCentralWidget(TheTable(self))
if __name__ == '__main__':
app = QtGui.QApplication(sys.argv)
frame = MainWindow()
frame.show()
app.exec_()
Updating PySide to the latest version resolves the issue.
It seems that the default combobox delegate is messing up with the data it receives.You could have fixed that with a custom delegate to paint the correct data. But since you have already solved it, Congratulations!.