How do I modify spacing in nested PyQt layouts? - python

Currently, I have a nested QVBoxLayout in the first column of a QHBoxLayout, but no matter my changes to .setContentMargins or .setSpacing nothing changes in that first column.
import sys
import io
from PyQt5.QtWidgets import *
from PyQt5.QtWebEngineWidgets import QWebEngineView
class MyApp(QWidget):
def __init__(self):
super().__init__()
# Main widget/window
self.setWindowTitle('Test')
self.window_width, self.window_height = 1600, 900
self.setMinimumSize(self.window_width, self.window_height)
layout = QHBoxLayout()
self.setLayout(layout)
leftside = QWidget()
leftlayout = QVBoxLayout()
# Creating textbox and adding to leftside GUI
lineEdit = QLineEdit()
leftlayout.addWidget(lineEdit)
leftlayout.addWidget(QPushButton('Placeholder'))
leftside.setLayout(leftlayout)
# Adding both widgets to main layout
testWidget = QWidget()
testWidget.setStyleSheet("background-color: blue")
layout.addWidget(leftside, 2)
layout.addWidget(testWidget, 8)
if __name__ == '__main__':
app = QApplication(sys.argv)
app.setStyleSheet('''
QWidget {
font-size: 20px;
}
''')
myApp = MyApp()
myApp.show()
try:
sys.exit(app.exec_())
except SystemExit:
print('Closing Window...')
Leaves me with this result:
What I want:

Use addStretch() method:
class MyApp(QWidget):
def __init__(self, parent=None):
super().__init__(parent)
self.setWindowTitle("Test")
self.window_width, self.window_height = 1600, 900
self.setMinimumSize(self.window_width, self.window_height)
leftside = QWidget()
leftlayout = QVBoxLayout(leftside)
lineEdit = QLineEdit()
leftlayout.addWidget(lineEdit)
leftlayout.addWidget(QPushButton("Placeholder"))
leftlayout.addStretch()
testWidget = QWidget()
testWidget.setStyleSheet("background-color: blue")
layout = QHBoxLayout(self)
layout.addWidget(leftside)
layout.addWidget(testWidget, stretch=1)

Related

How do I programmatically change the parent of a layout

I want to be able to move a layout to another layout based on a user input. I have the following code which does not appear to work for me. If I switch lines 31 and 34 so that they operate on the widget rather than the layout then I get the expected behaviour but I am hoping to operate on all widgets within a layout by just moving the layout.
import sys
from PyQt5.QtWidgets import QPushButton, QWidget, QHBoxLayout, QLabel, QApplication, QVBoxLayout
class b(QWidget):
def __init__(self, name):
super(b, self).__init__()
self.layout = QVBoxLayout(self)
lbl_1 = QLabel(name)
self.layout.addWidget(lbl_1)
class a(QWidget):
def __init__(self):
super(a, self).__init__()
self.layout = QHBoxLayout(self)
self.widget_1 = b('widget 1')
self.widget_2 = b('widget 2')
self.layout.addWidget(self.widget_1)
self.layout.addWidget(self.widget_2)
self.button_layout = QHBoxLayout()
self.move_layout = QPushButton('Move to other layout')
self.move_layout.clicked.connect(lambda: self.move_button())
self.button_layout.addWidget(self.move_layout)
self.widget = 'widget_2'
self.widget_2.layout.addLayout(self.button_layout)
def move_button(self):
if self.widget == 'widget_2':
self.widget_1.layout.addLayout(self.button_layout)
self.widget = 'widget_1'
else:
self.widget_2.layout.addLayout(self.button_layout)
self.widget = 'widget_2'
print('moved widget to {}'.format(self.widget))
if __name__ == '__main__':
app = QApplication(sys.argv)
window = a()
window.show()
sys.exit(app.exec_())
Edit: to clarify, In the example above, the layout I want to move (self.button_layout) is a child layout of self.widget_2.layout. When I click the pushbutton, I want the self.button_layout to be set as a child layout of self.widget_1.layout. Essentially it will do what the code below does but using addLayout instead of addWidget.
import sys
from PyQt5.QtWidgets import QPushButton, QWidget, QHBoxLayout, QLabel, QApplication, QVBoxLayout
class b(QWidget):
def __init__(self, name):
super(b, self).__init__()
self.layout = QVBoxLayout(self)
lbl_1 = QLabel(name)
self.layout.addWidget(lbl_1)
class a(QWidget):
def __init__(self):
super(a, self).__init__()
self.layout = QHBoxLayout(self)
self.widget_1 = b('widget 1')
self.widget_2 = b('widget 2')
self.layout.addWidget(self.widget_1)
self.layout.addWidget(self.widget_2)
self.button_layout = QHBoxLayout()
self.move_layout = QPushButton('Move to other layout')
self.move_layout.clicked.connect(lambda: self.move_button())
self.button_layout.addWidget(self.move_layout)
self.widget = 'widget_2'
self.widget_2.layout.addLayout(self.button_layout)
def move_button(self):
if self.widget == 'widget_2':
self.widget_1.layout.addWidget(self.move_layout)
self.widget = 'widget_1'
else:
self.widget_2.layout.addWidget(self.move_layout)
self.widget = 'widget_2'
print('moved widget to {}'.format(self.widget))
if __name__ == '__main__':
app = QApplication(sys.argv)
window = a()
window.show()
sys.exit(app.exec_())
The problem is that if a layout has a parent then it cannot be changed as the error message indicates:
QLayout::addChildLayout: layout "" already has a parent
One possible solution is to remove the parent:
def move_button(self):
self.button_layout.setParent(None)
if self.widget == "widget_2":
self.widget_1.layout.addLayout(self.button_layout)
self.widget = "widget_1"
else:
self.widget_2.layout.addLayout(self.button_layout)
self.widget = "widget_2"
print("moved widget to {}".format(self.widget))
Another alternative is to place the layout in a QWidget that is the container and that place it in the required layout:
class a(QWidget):
def __init__(self):
super(a, self).__init__()
layout = QHBoxLayout(self)
self.widget_1 = b("widget 1")
self.widget_2 = b("widget 2")
layout.addWidget(self.widget_1)
layout.addWidget(self.widget_2)
self.container = QWidget()
container_layout = QHBoxLayout(self.container)
button = QPushButton("Move to other layout")
button.clicked.connect(self.move_button)
container_layout.addWidget(button)
self.widget = "widget_1"
self.move_button()
def move_button(self):
if self.widget == "widget_2":
self.widget_1.layout.addWidget(self.container)
self.widget = "widget_1"
else:
self.widget_2.layout.addWidget(self.container)
self.widget = "widget_2"
print("moved widget to {}".format(self.widget))

Python using QGridLayout not add widget

I'm new to Qt5, I have a simple QGridLayout layout mask .
I want to create a windows with the widget resize with resize of window
this is the code
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtWidgets import QFileDialog ,QVBoxLayout,QGroupBox,QGridLayout
class MainWindow(QtWidgets.QMainWindow, QtWidgets.QFileDialog, QtWidgets.QLineEdit):
def __init__(self):
super().__init__()
self.title = "Calcolo Hash"
self.top = 100
self.left = 100
self.width = 800
self.height = 330
self.InitWindow()
def InitWindow(self):
self.setWindowIcon(QtGui.QIcon("icona_aprie.png"))
self.setWindowTitle(self.title)
self.setGeometry(self.top, self.left, self.width, self.height)
self.creamaschera()
self.show()
def creamaschera(self):
print ("creazione maschera")
layout = QtWidgets.QGridLayout()
self.txtcartella = QtWidgets.QLineEdit()
self.lblprova = QtWidgets.QLabel("Please enter new name:")
# self.txtcartella.setGeometry(QtCore.QRect(10, 10, 301, 20))
# self.txtcartella.setObjectName("txtcartella")
layout.addWidget(self.lblprova,0,0)
layout.addWidget(self.txtcartella,0,1)
self.setLayout(layout)
# self.horizontalGroupBox.setLayout(layout)
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
w = MainWindow()
#w.show()
sys.exit(app.exec_())
but when I run the mask is empy.
I make the base with Qt5 designer and convert it to python. I want to refactor the class in a best workout.
Where is the error?
You should setLayout in a widget rather than setting it to the MainWindow since you are using the MainWindow class itself and while accessing the methods and properties of the class MainWindow you can be more specific
import sys
from PyQt5 import QtCore, QtGui
from PyQt5.QtWidgets import (QLineEdit, QMainWindow, QWidget,
QGridLayout, QLabel, QApplication)
class MainWindow(QMainWindow):
def __init__(self, *args, **kwargs):
super(MainWindow, self).__init__(*args, **kwargs)
self.title = "Calcolo Hash"
self.top = 100
self.left = 100
self.width = 800
self.height = 330
self.InitWindow()
def InitWindow(self):
self.setWindowIcon(QtGui.QIcon("icona_aprie.png"))
self.setWindowTitle(self.title)
self.setGeometry(self.top, self.left, self.width, self.height)
self.creamaschera()
def creamaschera(self):
print("creazione maschera")
Layout = QGridLayout()
self.txtcartella = QLineEdit()
self.lblprova = QLabel("Enter Your Name")
self.lblprova.setGeometry(QtCore.QRect(15, 15, 301, 20))
self.txtcartella.setObjectName("txtcartella")
Layout.addWidget(self.lblprova, 0, 0)
Layout.addWidget(self.txtcartella, 0, 1)
# Widget to setLayout in it since you are using MainWindow as an Class
widget = QWidget()
widget.setLayout(Layout)
# SetCentralWidget without this widget won't be placed
self.setCentralWidget(widget)
# self.horizontalGroupBox.setLayout(layout)
if __name__ == "__main__":
app = QApplication(sys.argv)
MainWindow = MainWindow()
MainWindow.show()
sys.exit(app.exec_())

Print LineEdit text on a button press

How do I alter the following code to make it print whatever is written in line edit widget when 'OK' button is pressed? The current version returns "'Example' object has no attribute 'textbox'" error.
import sys
from PyQt5.QtWidgets import QApplication, QWidget,QPushButton,QLineEdit, QHBoxLayout, QLabel, QVBoxLayout
from PyQt5.QtGui import QIcon
class Example(QWidget):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
label = QLabel('Keyword')
button = QPushButton('OK')
textbox = QLineEdit()
hbox = QHBoxLayout()
hbox.addWidget(label)
hbox.addWidget(textbox)
hbox.addWidget(button)
vbox = QVBoxLayout()
vbox.addLayout(hbox)
vbox.addStretch(1)
button.clicked.connect(self.button_clicked)
self.setLayout(vbox)
self.setGeometry(300, 300, 300, 220)
self.setWindowTitle('Icon')
self.setWindowIcon(QIcon('web.png'))
self.show()
def button_clicked(self):
print(self.textbox.text())
if __name__ == '__main__':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
`
if you want that a variable can be accessed in all parts of the class as in your case is the button_clicked method you must make it a member of the class for it you must use self when you create it.
class Example(QWidget):
[...]
def initUI(self):
label = QLabel('Keyword')
button = QPushButton('OK')
self.textbox = QLineEdit() # change this line
hbox = QHBoxLayout()
hbox.addWidget(label)
hbox.addWidget(self.textbox) # change this line

Building Qt Gui from few classes together

Below is a short example of my Gui. I am trying to split my Gui in few parts.
The elements of InputAxis should be on the same height (horizontal split) and self.recipient should be below them (vertical split).
In InputAxis I am trying to place a QLineEdit but in my Gui I don't see it.
import sys
from PySide import QtCore
from PySide import QtGui
class InputAxis(object):
def __init__(self):
self.frame = QtGui.QFrame()
self.input_interface = QtGui.QLineEdit()
self.form_layout = QtGui.QFormLayout()
def genAxis(self):
self.frame.setFrameShape(QtGui.QFrame.StyledPanel)
self.form_layout.addRow('&Input:', self.input_interface)
return self.frame
class Window(QtGui.QWidget):
def __init__(self):
QtGui.QWidget.__init__(self, parent = None)
self.layout = QtGui.QVBoxLayout()
self.form_layout = QtGui.QFormLayout()
self.axes = list()
self.axes.append(InputAxis())
self.axes.append(InputAxis())
self.splitter1 = QtGui.QSplitter(QtCore.Qt.Horizontal)
for axis in self.axes:
self.splitter1.addWidget(axis.genAxis())
self.form_layout.addWidget(self.splitter1)
self.setMinimumWidth(400)
self.recipient = QtGui.QLineEdit(self)
# Add it to the form layout with a label
self.form_layout.addRow('&Recipient:', self.recipient)
# Add the form layout to the main VBox layout
self.layout.addLayout(self.form_layout, 0)
# Set the VBox layout as the window's main layout
self.setLayout(self.layout)
QtGui.QApplication.setStyle( QtGui.QStyleFactory.create('Cleanlooks') )
def run(self):
self.show()
def main():
qt_app = QtGui.QApplication(sys.argv)
window = Window()
window.run()
sys.exit(qt_app.exec_())
if __name__=="__main__":
main()
the reason it did not work was this line:
self.form_layout = QtGui.QFormLayout()
It should be:
self.form_layout = QtGui.QFormLayout(self.frame)

widgets are not expandig according to window size

what is mistake in this code that prevents widgets from expanding according to window size ?
class FeedbackWindow(QWidget):
def __init__(self):
QWidget.__init__(self)
self.main_layout = QVBoxLayout(self)
self.main_widget = QWidget(self)
self.main_widget.setLayout(self.main_layout)
self.title_label = QLabel("Tell us what you think:")
self.feedback_text_editor = QTextEdit()
self.send_button = QPushButton("Send")
self.main_layout.addWidget(self.title_label)
self.main_layout.addWidget(self.feedback_text_editor)
self.main_layout.addWidget(self.send_button)
self.setWindowTitle("Feedback")
self.setGeometry(200,120,300,300)
if __name__ == "__main__":
app = QApplication(sys.argv)
w = FeedbackWindow()
w.show()
app.exec_()
the main layout and widget are connected to self, so it should take its dimension.
The code does not use self.main_widget. Remove self.main_widget:
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
class FeedbackWindow(QWidget):
def __init__(self):
QWidget.__init__(self)
self.main_layout = QVBoxLayout(self)
#self.main_widget = QWidget(self) # main_widget is not used.
#self.main_widget.setLayout(self.main_layout)
self.setLayout(self.main_layout)
self.title_label = QLabel("Tell us what you think:")
self.feedback_text_editor = QTextEdit()
self.send_button = QPushButton("Send")
self.main_layout.addWidget(self.title_label)
self.main_layout.addWidget(self.feedback_text_editor)
self.main_layout.addWidget(self.send_button)
self.setWindowTitle("Feedback")
self.setGeometry(200,120,300,300)
if __name__ == "__main__":
app = QApplication(sys.argv)
w = FeedbackWindow()
w.show()
app.exec_()
Remove
self.main_widget = QWidget(self)
self.main_widget.setLayout(self.main_layout)
You don't need them. In your implementation, the layout is set on self.main_widget which is NOT the main widget. Your main widget is your FeedbackWindows itself. When you call self.main_layout = QVBoxLayout(self), it implicitely apply the layout on the main widget.

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