Porting from QT4.6 to QT5

[Christian Ehrlicher]

And make sure to not include the qt4 headers by accident - this can happen easily and create a lot of strange compiler errors...

[Qt Enthusiast]

Hi All
https://forum.qt.io/topic/91657/compilation-errors-when-porting-from-qt4-to-qt5/2

Can someone guide me how to install plugin for QMotifyStyle

[SGaist]

As this 6 year old blog post explains, these styles have moved to the QtStylePlugins module.

[Qt Enthusiast]

@SGaist
how to install the plugin it is still not clear to me if you can directly suggest the code changes

[jsulm]

@Qt-Enthusiast With a short search you can find: https://forum.qt.io/topic/65912/how-to-install-qtstyleplugins/7

[Qt Enthusiast]

ui_widget.h:177:119: error: 'UnicodeUTF8' is not a member of 'QApplication'
6987 browser->xt(QApplication::translate("exportWidget", "View in browser after exporting", 0, QApplication::UnicodeUTF8));

how to solve this issue and ui_widget.h is generated by uic

[Qt Enthusiast]

I am getting a lot of issues when ui files

[Christian Ehrlicher]

You're using the wrong uic (the one from Qt4) as it seems. Make sure to recreate your Makefiles with qmake for Qt5!

[SGaist]

One more thing, ensure that your source tree doesn't contain any generated file e.g. ui_*.h, etc. only original sources, .qrc, .ui file etc.

[Qt Enthusiast]

I am getting following error

how to solve this error

QString myString
error: 'class QString' has no member named 'toAscii'
execute(myString.toAscii();

[mrjj]

@Qt-Enthusiast
Its in the docs. i linked before.
https://wiki.qt.io/Transition_from_Qt_4.x_to_Qt5#toAscii.28.29_and_fromAscii.28.29_Methods_are_deprecated

[Qt Enthusiast]

One more question, I am getting following errors

void myClass::mythod() {
bool x = FALSE;
booly = TRUE;
}

error: 'FALSE' was not declared in this scope

any reason why and how to solve this issue

is there FALSE is declared in qt4 source code

[mrjj]

@Qt-Enthusiast
just use the c++ versions
true
false
(in small letters)

[Qt Enthusiast]

what is significance of FALSE and TRUE in Qt4

[Qt Enthusiast]

Also I am getting an error
mainwindow.h:17:0: error: "Q_NULLPTR" redefined [-Werror]

is Q_NULLPTR defined in SRC of QT5

[jsulm]

@Qt-Enthusiast Please post your code (mainwindow.h).
Also it is better to use nullptr from C++11 now.

[Qt Enthusiast]

@mrjj
is FALSE and TRUE defined in qt4 code

[JKSH]

@Qt-Enthusiast said in Porting from QT4.6 to QT5:

is FALSE and TRUE defined in qt4 code

No.

[Qt Enthusiast]

Then why I am getting this error when I am changing the library to Qt5

[jsulm]

@Qt-Enthusiast Do you use same compiler for both Qt versions?