Cannot open include file: 'QXmlSimpleReader': No such file or directory

[jpn]

There are a few errors in your .pro file:

TARGET = IconView
TEMPLATE = app
SOURCES += main.cpp \
    widget.cpp \ # <-- remove '\', the list of sources doesn't continue on the next line
 
HEADERS += widget.h \ # <-- remove '\', the list of headers doesn't continue on the next line
 
FORMS += widget.ui \ # <-- remove '\', the list of forms doesn't continue on the next line
 
RESOURCES += res.qrc
 
Qt += xml # <-- it should be "QT", not "Qt"

TARGET = IconView
TEMPLATE = app
SOURCES += main.cpp \
    widget.cpp \ # <-- remove '\', the list of sources doesn't continue on the next line

HEADERS += widget.h \ # <-- remove '\', the list of headers doesn't continue on the next line

FORMS += widget.ui \ # <-- remove '\', the list of forms doesn't continue on the next line

RESOURCES += res.qrc

Qt += xml # <-- it should be "QT", not "Qt"

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[been_1990]

Ok, compiling in QtCreator , both #include <QXmlSimpleReader> and #include <QtSql> work. But now what about #include <QtXmlPatterns>? It doesnt work. Gives me the same error.
.pro:

TARGET = IconView
TEMPLATE = app
SOURCES += main.cpp \
    widget.cpp 
 
HEADERS += widget.h 
 
FORMS += widget.ui 
 
RESOURCES += res.qrc
 
QT += xml
QT += sql

TARGET = IconView
TEMPLATE = app
SOURCES += main.cpp \
    widget.cpp 

HEADERS += widget.h 

FORMS += widget.ui 

RESOURCES += res.qrc

QT += xml
QT += sql

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[Lykurg]

Ok, compiling in QtCreator , both #include <QXmlSimpleReader> and #include <QtSql> work. But now what about #include <QtXmlPatterns>?

Come on, read the documentation! It's the same like the xml-module. Doc under QtXmlPatterns->Running the query engine from your Qt application!

[been_1990]

Ok, thanks for the help! Problem solved!