this has nothing to do with Qt.
std::to_string is C++11, you have to make sure you have a recent enough compiler and to enable C++11 features. If you use Qt Creator you should add CONFIG += c++11 in your .pro file and re-run qmake
Alternatively you can #include <sstream> and use std::stringstream gstream; gstream << 4; std::string g=gstream.str();
Actually, while I'd deleted the action code from mainwindow.cpp, I hadn't deleted its prototype in mainwindow.h. That's what the compiler was complaining about. So I deleted it in the .h and then ran Build -> Clean All. Doing that removed the reference to the deleted action in the moc file. Problem solved. Thanks again for your help.
Thank you for your response. I understand exactly what you're talking about. This is what I needed, I just didn't know how to go about it. I'll get busy with this and see if I can accomplish what you laid out for me. Thanks again. Very much appreciated.
Anyway, the bug is in line 61 in = &inFile; - you assign a variable created on a stack to variable in. In the next line, the inFile goes out of scope and is deleted. So when you try to access in later in the code, it segfaults.
Thanks !! . I know it's not Qt problem but that's why i posted it in C++ section
I would guess that is indeed the reason if none of those work! It always helps if you tell us which OS you are under, especially if it's not Windows! I would imagine this is a desktop-thing, so more than Lubuntu what is probably relevant is which desktop manager you are using. And it may be that your manager does not allow you not to have an icon....
I am using Linux - Lubuntu which has LXDE. Is there anyway to fix this? Is there any other way in QT to show a frame-less window/dialog/message/label/etc without a task-bar entry?
Can you specifically explain to me why Qt 5 is better than Qt4? Are you talking about Qt service?
Qt 4 reached End-of-Life status in December 2015. This means it is no longer supported -- it will not receive any new features, bug fixes, or security fixes.
If someone finds a security vulnerability in Qt 4, that means they could attack any computer that runs Qt 4 software. The user of the software will have no protection because the flaw will never be fixed. In contrast, if such a vulnerability is found in a supported version of Qt 5, the vulnerability will be fixed urgently so that users cannot be attacked.
If you find a bug in Qt 4 that affects your project, there is not much you can do about it -- you'll need to find your own workaround to the bug or patch Qt yourself. In contrast, if you find a bug in a supported version of Qt 5, you can file a bug report and there's a good chance it will be fixed.
In any case, better have some more information about your project otherwise it's only going to be speculations.
What specific kind of information?
For starters: What is your development PC's OS? What is your deployment target's OS? Will the final product be released to customers, or is it for internal use only? How do you plan to maintain the project? Which features of Qt do you plan to use?
I use Eigen on a daily basis, there's no real setting up to use it - it's a template library, meaning only headers. You only add its location to the INCLUDEPATH variable in your project file and you're good to go (see @JKSH's link and here). Since I use linux and I already have eigen in my system path, I don't even do that step, I just code.
A piece of advice for after you get it working:
Don't use auto with Eigen! People have been bitten by it, and there's even a dedicated page in the docs why.
@VRonin I don't doubt that Visual Studio can do this, my poins are
qmake doesn't have native way to set source-specific flags, you need to create your own custom target with all gory details of building C++ file, so it's much easier to move it into library
I don't know if mixing EH flags in the same binary is reliable with MSVC