Code cleanup

The Mixxx codebase has been around for a long time and has had many hands in it. Major parts of it have been re-written over time and as a result, it has accumulated a number of problems that, if fixed, would make future work easier and help fix current and avoid future bugs.

Here is a high-level list of things to do to make this happen:

• Remove all Qt version 3 code - See code branch https://code.launchpad.net/~mixxxdevelopers/mixxx/qt3-removal
  • Search the code for ”Qt3”, ”QT3”, and ”Q3” and replace with Qt4 equivalents
• Address all developer questions and concerns in code comments
  • Search the code for each of the following and fix (discuss with others as needed):
    • TODO

    • FIXME

    • XXX
    • hack
    • wtf
    • why
    • ?!
• Replace deprecated code
  1. Save the compiler output from a clean build
  2. Search for ”deprecated”
  3. Replace all implicated code (this page might be helpful)
• Address all warnings
  1. Save the compiler output from a clean build
  2. Search for ”warning”
  3. Determine if the warning is avoidable (unused variables for example,) and if so, fix it. If not, make note of why.
     • For unused variables, use Q_UNUSED(name); in the method body:

       void MyClass::MyMethod(int myArg) { Q_UNUSED(myArg); }

       This suppresses compiler warnings and has the added nicety of documenting that the argument is intended to go unused.