python - PyQt lineEdit on textEdited signal value lost after function call

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Learn more about Teams # connecting combobox to slot/function get_baffle_number self.baffle_number_combobox.currentIndexChanged.connect(get_baffle_number) # connecting PushButton action "clicked" to function on_click self.pushButton.clicked.connect(on_click) #connecting lineEdit to slot/function get_baffle_cost self.baffle_cost_lineEdit.textEdited.connect(get_baffle_cost) @pyqtSlot() def get_baffle_cost(text): baffle_cost = text return baffle_cost def get_baffle_number(text): #add 1 to the index returned by comboBox to get the number desired by user baffle_number = text + 1 return baffle_number def calc_baffle_cost(): test_total = (get_baffle_cost() * get_baffle_number()) return test_total @pyqtSlot() def on_click(self): baffle_cost = calc_baffle_cost() print(baffle_cost)

After I connect that lineEdit to the function via the pyqtSlot() , it seems to get the value, but immediately dumps it if I attempt to use baffle_cost from another function. I watch it in PyCharm during debugging and it holds it just as long as the lineEdit has focus it seems. Pressing the pushButton is right when it loses its value.

I cannot use the returned baffle_cost anywhere from get_baffle_cost .

Am I missing something? The furthest I've got is that attempting to simply print calc_baffle_cost() and a hexadecimal is printed. I am assuming that is a memory location, but can't be sure. (new to Python)

Sorry if this isn't enough information. I am simply attempting to take baffle_cost from a lineEdit and multiplying that by a value taken from a comboBox .

The


    QPushButton

is when the user is done selecting from


    baffle_number_combobox

and


    baffle_cost_lineEdit

which simply multiplies them. Well, this is what I want it to do, but I lose the values from the


    baffle_cost_lineEdit

the second it loses focus.


    test_total

I would like (for now) printed


    on_click

– NosirrahSec Jun 8, 2018 at 19:48

It seems my problem was two-fold, or more.

I was not correctly scoping my functions and not utilizing the right namespaces. (Sorry if this terminology is incorrect. I am new to Python and PyQt.)

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
    # sizing of widgets
    def retranslateUi(self, MainWindow):
    # UI stuff here QlineEdits, etc.
    self.baffle_cost_lineEdit.editingFinished.connect(self.get_baffle_cost)
    def get_baffle_cost(self):
        baffle_cost = self.baffle_cost_lineEdit.text()
        return baffle_cost
This needed to be in the same scope(indentation) as my retranslateUi() function in my Ui_MainWindow Class like above.
I think if I had better structured my project this wouldn't have been an issue. I have definitely learned my lesson about having it all in one script. (program.py)
The other issue(s) I encountered is that the PyQt function text() called from a QlineEdit returns a QString and not a str. I simply needed to cast it to a string.
I was losing the value because the function get_baffle_cost wasn't properly scoped with the baffle_cost_lineEdit
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