title: Qt: How to build a qt librabry project within an application project
body: <p>I have a qt library project that I want to use in several Qt application projects. The application project however should build the library as well, if its not already built. Is that possible?</p>
  
  <p>The accepted answer in the following question shows how to create the library and application projects. I guess one has to build the library first before one can use them in the application projects:
  <a href="https://stackoverflow.com/questions/2870637/what-is-the-easiest-way-to-reference-libraries-in-qt-projects">What is the easiest way to reference libraries in Qt projects?</a></p>