How to check QLabel exist or not in PyQT5

krsapril24 · 1 Oct 2018, 17:04

I am creating dynamically QLabel and QLineEdit, Before creating them i need to know if already label already exist or not. Please helpme, Thanks in Advance

JonB · 10 Jan 2018, 17:15

@krsapril24
You have to define what you mean by "if already label already exist or not.". Any label that is a child of such and such? A label with same text? A label where you previously used setObjectName() to something we can search for now?

Or, maybe you mean: when you first create a widget you often save it in self (e.g. a QDialog), and you want to know if you have previously done so?

If that's what you mean, you can do that by putting into your dialog's __init__():

self.label = None
self.lineedit = None

and you can create first time only with:

if not self.label:
    self.label = QLabel()
    self.lineedit = QLineEdit()

Or what?

krsapril24 · 2 Oct 2018, 12:42

Hi created like this

if(i==1):

            '''self.formLayout.removeWidget(self.childCmpName1LineEdit.hide())
            self.formLayout.removeWidget(self.childCmpName1)
            self.formLayout.removeWidget(self.parentCmpName2LineEdit)
            self.formLayout.removeWidget(self.parentCmpName2)
            self.formLayout.removeWidget(self.self.childCmpNameLineEdit)
            self.formLayout.removeWidget(self.self.childCmpName)
            self.formLayout.removeWidget(self.parentCmpName3LineEdit)
            self.formLayout.removeWidget(self.parentCmpName3)
            self.formLayout.removeWidget(self.branchNameLineEdit)
            self.formLayout.removeWidget(self.branchName)'''

            self.parentCmpName1 = QLabel(self.formLayoutWidget)
            self.parentCmpName1.setObjectName("parentCompanyName")
            self.parentCmpName1.setText("Parent Company Name* : ")
            self.formLayout.setWidget(13, QFormLayout.LabelRole, self.parentCmpName1)
            self.parentCmpName1LineEdit = QLineEdit(self.formLayoutWidget)
            self.formLayout.setWidget(13, QFormLayout.FieldRole, self.parentCmpName1LineEdit)
    elif(i==2):
        '''self.formLayout.removeWidget(self.parentCmpName1LineEdit)
        self.formLayout.removeWidget(self.parentCmpName1)'''

        if(self.parentCmpName1.hasSelectedText()):
            print("hi")

        '''if(self.parentCmpName1LineEdit):
            self.parentCmpName1LineEdit.hide()'''

        self.parentCmpName2 = QLabel(self.formLayoutWidget)
        self.parentCmpName2.setObjectName("parentCompanyName")
        self.parentCmpName2.setText("Parent Company Name* : ")
        self.formLayout.setWidget(13, QFormLayout.LabelRole, self.parentCmpName2)
        self.parentCmpName2LineEdit = QLineEdit(self.formLayoutWidget)
        self.formLayout.setWidget(13, QFormLayout.FieldRole, self.parentCmpName2LineEdit)

        self.childCmpName = QLabel(self.formLayoutWidget)
        self.childCmpName.setObjectName("childCompanyName")
        self.childCmpName.setText("Child Company Name* : ")
        self.formLayout.setWidget(14, QFormLayout.LabelRole, self.childCmpName)
        self.childCmpNameLineEdit = QLineEdit(self.formLayoutWidget)
        self.formLayout.setWidget(14, QFormLayout.FieldRole, self.childCmpNameLineEdit)
    elif(i==3):
        '''self.formLayout.removeWidget(self.parentCmpName1LineEdit)
        self.formLayout.removeWidget(self.parentCmpName1)
        self.formLayout.removeWidget(self.parentCmpName2LineEdit)
        self.formLayout.removeWidget(self.parentCmpName2)
        self.formLayout.removeWidget(self.self.childCmpNameLineEdit)
        self.formLayout.removeWidget(self.self.childCmpName)'''

        self.parentCmpName3 = QLabel(self.formLayoutWidget)
        self.parentCmpName3.setObjectName("parentCompanyName")
        self.parentCmpName3.setText("Parent Company Name* : ")
        self.formLayout.setWidget(13, QFormLayout.LabelRole, self.parentCmpName3)
        self.parentCmpName3LineEdit = QLineEdit(self.formLayoutWidget)
        self.formLayout.setWidget(13, QFormLayout.FieldRole, self.parentCmpName3LineEdit)

        self.childCmpName1 = QLabel(self.formLayoutWidget)
        self.childCmpName1.setObjectName("childCompanyName")
        self.childCmpName1.setText("Child Company Name* : ")
        self.formLayout.setWidget(14, QFormLayout.LabelRole, self.childCmpName1)
        self.childCmpName1LineEdit = QLineEdit(self.formLayoutWidget)
        self.formLayout.setWidget(14, QFormLayout.FieldRole, self.childCmpName1LineEdit)

        self.branchName = QLabel(self.formLayoutWidget)
        self.branchName.setObjectName("branchName")
        self.branchName.setText("Branch Name* : ")
        self.formLayout.setWidget(15, QFormLayout.LabelRole, self.branchName)
        self.branchNameLineEdit = QLineEdit(self.formLayoutWidget)
        self.formLayout.setWidget(15, QFormLayout.FieldRole, self.branchNameLineEdit)

i want to remove repeated Qlabels and QLine edits on different combobox selection. Kindly help me.

JonB · wrote on 2 Oct 2018, 12:42

@krsapril24
Sorry, that's 100 lines of code. I don't which bit is wrong. You seem to be doing some removeWidget() and some creating of widgets, so what exactly is the problem?

krsapril24 · wrote on 2 Oct 2018, 13:29

see if user select parent company i need to display only compnay name and if user select child company then i need to display parent company and child company.

so if user select only one at a time no problem it is working. if user select first child comapny then i need to hide parent company name if exist and then i need to display parent company and child company. in this situation i am facing problem. because parent company does not exist when select child company. so i need to hide if exist only. Please help me. iam struggling in this last 3 days.

SGaist · wrote on 2 Oct 2018, 21:38

Hi and welcome to devnet,

Where do you get the information about these companies from ?