Qt project files and PREFIX variable

Question

I included

PREFIX = /usr/local

inside my project file and then I run

Answer 1

If you like to pass PREFIX to qmake, so you can do as follow:

• Open Projects from left pan or using Ctrl+5 key
• Expand Build Steps
• Add PREFIX=/your/path/ into Additional arguments field

Answer 2

PREFIX doesn't mean anything in qmake files. The target for files is done via the target parameter. So if you want to make PREFIX determine the base location, such as /usr/local, you can do do something like this:

isEmpty(PREFIX) {
 PREFIX = /usr/local
}
TARGET = myapp
TARGET.path = $$PREFIX/

The isEmpty(PREFIX) will allow it to be changed during the command line call to qmake, e.g.

qmake PREFIX=/opt

Answer 3

That is INSTALL_ROOT variable on install, try
make install INSTALL_ROOT="your path"