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Thread: QList index out of range problem

  1. #1
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    Talking QList index out of range problem

    Hi to all!

    I have following method with its code:
    Qt Code:
    1. qint16 CApplicationSettings::searchSettingsForIndex(const QString& strHub, const QString& strKey)
    2. {
    3. if(m_SettingsValues.size()>0)
    4. for (qint16 iIndex=0; iIndex=m_SettingsValues.size(); iIndex++)
    5. if(m_SettingsValues.at(iIndex).strHub==strHub)
    6. if(m_SettingsValues.at(iIndex).strKey==strKey)
    7. return iIndex; // returns index of found record
    8.  
    9. return RECORD_NOT_FOUND; // not found
    10. }
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    Once called, the application crashes with following error:
    Qt Code:
    1. warning: Lowest section in C:\WINDOWS\system32\xpsp2res.dll is .rsrc at 20001000
    2. warning: QLayout: Cannot add null widget to QHBoxLayout/
    3.  
    4. Current language: auto; currently c++
    5. warning: ASSERT failure in QList<T>::at: "index out of range", file ../../../../Qt/4.3.4/include/QtCore/../../src/corelib/tools/qlist.h, line 391
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    It is obvious I try to read out of range record, but I simply do not get it why? This code seems perfect to me ... The app crashes in line 5 of method, in the first comparsion.
    Qt 5.3 Opensource & Creator 3.1.2

  2. #2
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    Default Re: QList index out of range problem

    The loop is incorrect. The second argument of the for statement should probably say "iIndex<m_SettingsValues.size()". Now you are asigning an invalid index there and so the loop tries to read after the last element of the list.

  3. The following user says thank you to wysota for this useful post:

    MarkoSan (26th March 2008)

  4. #3
    Join Date
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    Default Re: QList index out of range problem

    Ohhh, my good, what a retard mistake!!!! Thanks, wysota!!!
    Qt 5.3 Opensource & Creator 3.1.2

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