Finish rhythmic dictation exercise

[cecilios]

Things needed for releasing the exercise:

• Edit Tools for rhythmic dictation
  • Disable ToolBox when edition is disabled
  • It should be always possible to replace a specific toolbox (i.e. rhythm dictation) by the main one
    (a button on toolbox title?)
• Generate problems:
  • define level 1 syllabus
  • define melody fragments, keys, time signatures
  • algorithm for deciding how many measures
  • algorithm for deciding how many fragments and assigning measures
    to fragments
  • implement any new requirement in Composer
• Other issues:
  • virtual keyboard?
  • mark clef, key and time signature as non-editable
  • In rhythm dictation (percussion clef), noteheads must be cross
  • cursor must skip non-editable objects
  • backerase generates two paint events: cursor back and delete note
  • config:
    • max num times play problem is allowed
    • midi instrument for playing problem score
    • number of measures (or fragments)
    • first measure initially displayed
    • context type
  • dialog for options
  • video to explain exercise and ToolBox use