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Thread: Usage of QT::UserRole in Qtreewidgetitem

  1. #1
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    Default Usage of QT::UserRole in Qtreewidgetitem

    Hi,

    I am having issues with using Qt::UserRole with Qtreewidgetitem.

    Here's my code :

    Qt Code:
    1. UGS::AsciiString Hdrstr = "Header";
    2. QString str = QString::fromUtf8(Hdrstr.c_str());
    3. QVariant Headerqv(str);
    4.  
    5. RootWidget->setData(0, Qt::UserRole + 1, Headerqv);
    To copy to clipboard, switch view to plain text mode 

    And finally retrieving the value:

    Qt Code:
    1. StrValue = Widgetitem->data(0, Qt::UserRole + 1);
    2. QString strval = StrValue.toString();
    3.  
    4. if (strval.toStdString() == "Header")
    To copy to clipboard, switch view to plain text mode 
    In this line :
    if (strval.toStdString() == "Header")

    there's no value of the string. Can anyone suggest what am I doing wrong over here ?

    Thank you !

  2. #2
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    Default Re: Usage of QT::UserRole in Qtreewidgetitem

    Are RootWidget and Widgetitem the same pointer?

    Cheers,
    _

  3. #3
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    Default Re: Usage of QT::UserRole in Qtreewidgetitem

    They are different pointers but they are pointing to the same item. So, yeah they got same value.

    But even I do:
    Qt Code:
    1. RootWidget->setData(0, Qt::UserRole + 1, Headerqv);
    2.  
    3. QVariant StrValue = RootWidget->data(0, Qt::UserRole + 1);
    4. QString strval = StrValue.toString();
    5. string str = strval.toStdString();
    To copy to clipboard, switch view to plain text mode 

    To check the value right after setting the data, str value is still NULL , mean an empty string"" .

    Not sure why.

    Thanks,

  4. #4
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    Default Re: Usage of QT::UserRole in Qtreewidgetitem

    Quote Originally Posted by h4harman View Post
    They are different pointers but they are pointing to the same item.
    If it is not the same pointer, how can it be the same object?

    Quote Originally Posted by h4harman View Post
    But even I do:
    Qt Code:
    1. RootWidget->setData(0, Qt::UserRole + 1, Headerqv);
    2.  
    3. QVariant StrValue = RootWidget->data(0, Qt::UserRole + 1);
    4. QString strval = StrValue.toString();
    5. string str = strval.toStdString();
    To copy to clipboard, switch view to plain text mode 

    To check the value right after setting the data, str value is still NULL , mean an empty string"" .
    Have you checked Headerqv? Does it contain the string?

    Cheers,
    _

  5. #5
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    Default Re: Usage of QT::UserRole in Qtreewidgetitem

    If it is not the same pointer, how can it be the same object?
    Well I needed 2 pointers to point to the same address. So it's the same object coz they are pointing to the same value. I think that's what you wanted to say.

    But anyhow, I got the solution. I was just writing some extra lines of code for no reason. I did the following :


    Qt Code:
    1. QVariant Headerqv = QVariant("Header");
    2. RootWidget->setData(0, Qt::UserRole, Headerqv);
    3.  
    4. QVariant StrValue = RootWidget->data(0, Qt::UserRole);
    5. QString strval = StrValue.toString();
    6. string str = strval.toStdString();
    To copy to clipboard, switch view to plain text mode 

    But thanks for all the help

    Regards,

  6. #6
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    Default Re: Usage of QT::UserRole in Qtreewidgetitem

    If it is not the same pointer, how can it be the same object?
    I think now I know why you pointed that out. So it seems, widgets are individual objects. I can't use another widget item to point to it and use it values. I thought I could do that.

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