What's the correct line to include the plugin path ?
The only thing that seemed to work is:
Qt Code: 
  1. # LIBS += $$[QT_INSTALL_PLUGINS]/designer/libDbComboBox.so
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I have to tell it the library name. Shouldn't the compiler find it from the path setting ?
I've tried these lines but the compiler can't find it.

Qt Code: 
  1. LIBS += -L$$[QT_INSTALL_PLUGINS]/designer -llibDbComboBox
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/usr/bin/ld: cannot find -llibDbComboBox

Qt Code: 
  1. LIBS += -l$$[QT_INSTALL_PLUGINS]/designer
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/usr/bin/ld: cannot find -l/home/vince/qtsdk-2009.03/bin/designer

Qt Code: 
  1. LIBS += -L$$[QT_INSTALL_PLUGINS]/designer
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undefined reference to [all my methods]

The path IS a valid directory, using Qt 4.5.2 on Debian.