Changing Multiple Widget Styles from pushButton in a loop - pyqt5

Question

I am using PyQt5 to make a GUI, this GUI has several buttons on the top of the page which changes the index of the lower StackedWidget based on the selection. When the button is clicked, the selected button changes the style sheeet of that selected button to selected_style, but changes all others to unselected_style. I read the simplest and most universal way of doing this was to add single actions per line. But that has become quite redundant and culminates to excessive amounts of lines.This is currently being implemented by single lines, like:
self.pshBtn_1.clicked.connect(lambda: self.stckWdgt.setCurrentIndex(0))
self.pshBtn_1.clicked.connect(lambda: self.pshBtn_1.setStyleSheet(selected)
self.pshBtn_1.clicked.connect(lambda: self.pshBtn_2.setStyleSheet(unselected)
self.pshBtn_1.clicked.connect(lambda: self.pshBtn_3.setStyleSheet(unselected)
self.pshBtn_2.clicked.connect(lambda: self.stckWdgt.setCurrentIndex(1))
self.pshBtn_2.clicked.connect(lambda: self.pshBtn_2.setStyleSheet(selected)
self.pshBtn_2.clicked.connect(lambda: self.pshBtn_1.setStyleSheet(unselected)
self.pshBtn_2.clicked.connect(lambda: self.pshBtn_3.setStyleSheet(unselected)
# And so on, and so on, and so on
I attempted to loop through a list of the names of the buttons in a function under self, but I keep ending up with NameErrors. Something like:
self.pshBtn_1.clicked.connect(self.set_btn_style, pshBtn_1)
self.pshBtn_2.clicked.connect(self.set_btn_style, pshBtn_2)
self.pshBtn_3.clicked.connect(self.set_btn_style, pshBtn_3)
btn_dict = {pshBtn_1 : 0, pshBtn_2: 1, pshBtn_3: 2} #Button Name, Stacked Widget Index
def set_btn_style(self, var_name):
for i, j in btn_dict:
btn_name = i
idx = j
if btn_name == var_name:
self.keyname.setStyleSheet(button_selected)
self.stckWdgt.setCurrentIndex(idx))
else:
self.btn.setStyleSheet(button_unselected)
I guess the big question here is how can I have one function be used by several buttons or GUI actions, but pass in a specifc tableWidget, stackWidget, etc. as a parameter so I don't have to repeat some function 10 times for each button I want to use that function. Thanks.

Answer 1

Instead of setting a stylesheet each time the buttons are pressed, the simplest way is to enable the checkable property of the QPushButtons and thus use it as a filter in the Qt Style Sheet. To change the page and only one is selected, a QButtonGroup is used.
from PyQt5 import QtCore, QtWidgets
QSS = """
Button {
background-color: #00ff00;
}
Button:checked {
background-color: #ff0000;
}
"""
class Button(QtWidgets.QPushButton):
pass
class Widget(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Widget, self).__init__(parent)
page1 = QtWidgets.QLabel("page1", alignment=QtCore.Qt.AlignCenter)
page2 = QtWidgets.QLabel("page2", alignment=QtCore.Qt.AlignCenter)
page3 = QtWidgets.QLabel("page3", alignment=QtCore.Qt.AlignCenter)
options = ["Page1", "Page2", "Page3"]
stackedwidget = QtWidgets.QStackedWidget()
hlay = QtWidgets.QHBoxLayout()
group = QtWidgets.QButtonGroup(self)
group.buttonClicked[int].connect(stackedwidget.setCurrentIndex)
for i, (option, widget) in enumerate(zip(options, (page1, page2, page3))):
button = Button(text=option, checkable=True)
ix = stackedwidget.addWidget(widget)
group.addButton(button, ix)
hlay.addWidget(button)
if i == 0:
button.setChecked(True)
vbox = QtWidgets.QVBoxLayout(self)
vbox.addLayout(hlay)
vbox.addWidget(stackedwidget)
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
app.setStyle("fusion")
app.setStyleSheet(QSS)
w = Widget()
w.resize(640, 480)
w.show()
sys.exit(app.exec_())

Answer 2

I run into this often where I want to pass a widget name to another function. I was able to solve this by making a nested dictionary to link one item to the widget name I want to pass in. The function is called in a for loop within the main class. In the function I use self.sender() and sending_button.objectName() to get the name of the item I used to start the function.
class Ui_MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(Ui_MainWindow, self).__init__(parent)
self.setupUi(self)
# ^^ Up here would be a bunch of buttons I want to do something with
# Make a nested Dictionary to hold the string name of button,
# the actual widget name, and the stacked widget index it corresponds to.
self.btn_change_sel = {'pushButton_1': {self.pushButton_1: 0},
'pushButton_2': {self.pushButton_2: 1} }
# if any button is pressed, launch function.
for item in self.btn_change_sel.keys():
for button in self.btn_change_sel[item].keys():
button.clicked.connect(self.btn_style_change)
def btn_style_change(self):
sending_button = self.sender()
check_sender = str(sending_button.objectName()) # Get the string name of sender button
for sender_name in self.btn_change_sel.keys(): # Get string name to match
# If the clicked button matches the string value, do some stuff
if check_sender == sender_name:
for btn_item in self.btn_change_sel[sender_name].keys():
btn_item.setStyleSheet(self.button_selected)
for stack_idx in self.btn_change_sel[sender_name].values():
self.stackedWidget_all.setCurrentIndex(stack_idx)
# Do something with all other buttons not selected, change to a different style
if check_sender != sender_name:
for btn_item2 in self.btn_change_sel[sender_name].keys():
btn_item2.setStyleSheet(self.button_unselected)
So on this example, if the clicked button matches, it changes the stylesheet and selects the stackedWidget that corresponds to the button click. All others receive the Unselected style. This makes the displayed widget button different so you easily can tell which widget page your on.