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C++ Reference in QtCreator help

  • Hello all,

    I just started to learn C++ wiht QT and found that context help in QtCreator is very helpfull

    I downloaded C++ Reference from "C++ Reference wiki":http://www.cppreference.com/wiki/_media/about/cppreferencecom_feb09.zip

    I converted unpacked content from chm to qch file with content and index.

    It works fine, but context help in source editor doesn't work.

    Can anybody help me to understand how to make context help working with my compiled qch?

    I can upload if you need C++ reference in qch format and qt project qhp files.

  • Good question, I join to it.

    pavko, Please, give me qch-file with C++ reference, I need it.

  • I just added your qch file to Qt Creator's help via Tools->Options->Help->Documentatioin tab, pressed F1, and got cpp reference. Try to check Filters tab, there should be corresponding items checked for cpp reference.

  • I mean, that it doesn't work in text editor. For example, when you point on keyword (something like "void") pressing F1 - I want, that on the right side help about "void" apears. It doesn't works.

    So, I can't find solution to make CONTEXT help possible. I don't know how to turn it on with my compiled file.

    Anyway - thanks for help :)

  • Sorry, I just misunderstood the original issue.

  • Do you have a C++ project open? It appears to me that Qt Creator may not scan the source files for symbols unless a C++ project is open.

    Have you restarted Qt Creator? I have also found that sometimes Qt Creator needs to be restarted after the qch is registered with it.

  • Yes, I did this. Actualy I mean context help, like in "this post":http://qtcreator.blogspot.com/2009/07/context-sensitive-help.html

    Content and index are working fine.

  • The hover-and-hit-F1 context help works for me with the Qt Creator snapshot from Jun 7 (from revision b4bf0289b1, for Windows). If I hover-F1 over #include <algorithm>, it pulls up the algorithms page. If I hover-F1 over #include <vector>, it pulls up the vector page. If I hover over #include <numeric>, it does not work (probably because there is no numeric keyword in the index). The context help has been somewhat problematic, but it has been getting more reliable over time. I find recent development builds work more often than not.

  • bradley: We try not to break creator, but sometimes something does slip through... having said that: Most of the people working on qt creator do so using creator from the branch they work on, so we do tend to notice most breakages:-)

  • I tried with Qt Creator 2.0.1 and yes, the context help does not work. I did not debug the Qt Creator, but STL reference (available here: http://developer.qt.nokia.com/wiki/Qt_Creator_Documentation_Gallery) does work in the context mode. This makes me wonder if the context tags were generated correctly when the cppref.qch file was created?

  • I tried "cppref.qch" with Qt Creator 2.0.1. Context help works fine for functions (e.g. abs, ceil, atoi), but doesn't works for keywords (e.g. void, switch, public). But it's good enough :)

  • The context help (F1) seems only to work, if the correct #include statement is in the code. I tried "cppref.qch" and also the Linux Man Pages (available here http://developer.qt.nokia.com/wiki/Qt_Creator_Documentation_Gallery) with Qt Creator 2.2.1 and also the latest nightly build of 2.3.
    Here an example code to test the context help:

    @#include <QtCore/QCoreApplication>
    #include <cmath>
    #include <cstdio>
    #include <cstdlib>

    int main(int argc, char *argv[])
    QCoreApplication a(argc, argv);
    char name[] = "world";
    FILE *out = fopen( "output.txt", "w" );
    if( out != NULL )
    fprintf( out, "Hello %s\n", name );
    return a.exec();

    For example, for the math functions abs() and sqrt() the context help works only if <cmath> is included and recognized by QtCreator (cmath.h must be in the PATH or in INCLUDEPATH of the *.pro project file). The same behavior for rand() and <cstdlib>. But for printf, fprintf or fopen the context help does not work at all, even with <cstdio>. Also no context help for the keywords.

    Normally, a context help system should be independent of the syntax parser, i.e. the include files, as it happens often that one would like to know the correct include file for a specific function.

  • Same problem for QCoreApplication and its #include statement, as soon as the #include <QtCore/QCoreApplication> statement is commented (//) or removed, "QCoreApplication" change its color and no more context help via F1.
    So the problem seems to be general for all qch-help files and not only the C++-reference or Linux Man Pages help files. It is a problem of Qt Creator and not the help files or their context tags.
    I have put a bug-report here:

  • To finalize this thread - you can find cpp reference in qch format here "CPP-reference":http://en.cppreference.com/w/Cppreference:Archives

  • I took the liberty of adding that link to the "Qt Creator documentation gallery":https://qt-project.org/wiki/Qt_Creator_Documentation_Gallery (below the other link to and C++ reference in QCH format;-)

  • Qt Creator 2.8.1 here with "Linux Man Pages Qt Help integrated":http://shinnok.com/rants/2011/07/19/linux-man-pages-integration-with-qt-creator/

    It runs out something is still not right with recognising the right headers.

    In this example, F1 for the fabs function works:
    #include <math.h>
    int main()

    but in this, F1 for the printf does not work:
    #include <stdio.h>
    int main()

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