How do to add a library to my project?

[N3wb]

Thanks for all of your replies!

I tried your method faldżip, but can't seem to get it to work. Would it be better/more proper to use the QLibrary method that yogeshgokul posted? Either way, it looks like it's going to take me some time to figure this out. I'm just wondering which method I should pursue?

[kuzulis]

Simply connect the *. dll - not using QLibrary IMHO

[faldzip]

can you show us you *.pro file?

[kuzulis]

here : http://www.prog.org.ru/topic_8259_0.html

PS: Google translator to help

[N3wb]

Faldżip, thanks so much for helping. Here's my .pro file:

SOURCES += main.cpp \
    mainwindow.cpp \
    baction.cpp \
    caction.cpp \
    arrowbutton.cpp
HEADERS += main.h \
    mainwindow.h \
    baction.h \
    caction.h \
    arrowbutton.h
OTHER_FILES += readme.txt
 
INCLUDEPATH += C:\Users\Nathan\Desktop\qextserialport
LIBS += -LC:\Users\Nathan\Desktop\qextserialport -lqextserialport
 
CONFIG(debug, debug|release):LIBS += -lqextserialportd
CONFIG(release, debug|release):LIBS += -lqextserialport

SOURCES += main.cpp \
    mainwindow.cpp \
    baction.cpp \
    caction.cpp \
    arrowbutton.cpp
HEADERS += main.h \
    mainwindow.h \
    baction.h \
    caction.h \
    arrowbutton.h
OTHER_FILES += readme.txt

INCLUDEPATH += C:\Users\Nathan\Desktop\qextserialport
LIBS += -LC:\Users\Nathan\Desktop\qextserialport -lqextserialport

CONFIG(debug, debug|release):LIBS += -lqextserialportd
CONFIG(release, debug|release):LIBS += -lqextserialport

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The paths I put in there are to this folder: http://www.roboticsguy.com/qextserialport.zip

I'm really over my head here, I've never used DLLs before and have no idea what I'm doing I really appreciate your time and any advice you could give me.

[faldzip]

LIBS += -LC:\Users\Nathan\Desktop\qextserialport -lqextserialport
 
CONFIG(debug, debug|release):LIBS += -lqextserialportd
CONFIG(release, debug|release):LIBS += -lqextserialport

LIBS += -LC:\Users\Nathan\Desktop\qextserialport -lqextserialport
 
CONFIG(debug, debug|release):LIBS += -lqextserialportd
CONFIG(release, debug|release):LIBS += -lqextserialport

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in debug version you are linking to both versions of library... so remove -lqextserialport from the first line I pasted.
What does it mean it is not working? What errors you get? Are you using MinGW or VisualStudio?