QT5 and ä, ö, ü (Umlaut)
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Hi,
I have just chosen to update from QT4 to QT5. Unfortunately, all äs, ös and üs (Umlaute) do not show up properly. I then checked out the posts in the forum but none of the proposed solutions solved my issue.
Here is what I did with a QLabel, assuming that "QLabel* label = new QLabel;" is somewhere else.
label->setText("ä"); ---> does not show any ä
QString tt = tr( "äöü");
label->setText(tt); ---> does not show any äQTextCodec *codec = QTextCodec::codecForName("UTF-8");
QString tt = codec->toUnicode( "äöü");
label->setText(tt); ---> does not show any äQString tt = QString::fromUtf8( "äöü");
label->setText(tt); ---> does not show any äHas anybody got any other idea or is this just a bug? Things worked without any problem with QT4..
I tried also to do it as the designer generated code does but designer generates ascii codes (\303)
directly which is not an option since I get some data to show from non-QT subroutines.I use Microsoft Visual Studio 2012 (which should be UTF-8 ) and Unicode, QT 5.1.1 x86 (32 bit) downloaded as the binary package from the web page.
Thank you for any help
Hauke
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Hi,
I haven't tried this myself (I'm not at a machine with VS 2012), but try marking your strings as Unicode literals:
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QString tt(u"äöü");// OR
QString tt = QStringLiteral("äöü");
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Hi,
thank you, that helped: QStringLiteral has been the working solution. u"äüö" is only for gcc - is my feeling, I did not really investigate it but compiler complained about it.
But this brings me to the follow-up question: What if I want to do the following:
Instead of
->
QString tt = QStringLiteral("ä");I would like to do it
->
std::string str = "ä";
QString tt = QStringLiteral(str.c_str());This does not work with QStringLiteral as it produces a compiler error message. This situation is very common, e.g., I am working with a german PC and list up audio devices with portaudio, the name "primärer Audiotreiber" is returned as a std::string or const char*.
Thank you and best regards
Hauke
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Hrmm... petition Microsoft to hurry up and implement Unicode string literal support? :-/ "u" is in the C++11 standard, but MSVC 2012 doesn't support it: http://blogs.msdn.com/b/vcblog/archive/2011/09/12/10209291.aspx
From "this blog":http://msdn.microsoft.com/en-us/library/vstudio/69ze775t.aspx, L"äöü" might work in MSVC.
[quote]
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std::wstring str = “ä”; // EDIT: wstring, not string
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[/quote]Make sure you never write code that does that. std::string stores an array of bytes. Unicode characters can be multi-byte.You can probably successfully store and retrieve unicode bytes like this...
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std::string str = L"ä";
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... but the "ä" character is 2 bytes long, so str.length() == 2![quote]
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QString tt = QStringLiteral(str.c_str());
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[/quote]That is a compilation error because QStringLiteral is a macro that constructs a QString at compile-time, but str.c_str() can only be evaluated at run-time.Use one of the QString::from***() functions (depending on how your string was encoded).
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In case you're wondering why QStringLiteral behaves this way, consider these two strings:
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QString str1 = "abc";
QString str2(QStringLiteral("abc"));
@str1 requires data conversion at run-time, but str2 does not (because the QString was created at compile-time). Thus, str2 is more efficient -- this is why QStringLiteral exists.
P.S. Please add "@" before and after your code segments. It makes it much easier to read.
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Hi, thank you for your answer. I think I have understood the problem now - what I need is the Latin1 encoding for the ASCII Bytes. I did not even know that it is Latin1. To use std::string as described worked for many years without any problem for me ...
Let me just comment on two things:
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std::string str = "äü";
@str.size() gives me a 2.
In order to use L"ä", I would need to use std::wstring instead of std::string. Otherwise I get a compiler error.
QString::fromLatin1 seems to have solved all problems.
Thank you and have a nice weekend
Hauke
