Drag fragments in sequence diagram

[Tony Chen]

In the sequence diagram view, user should be able to drag fragments up/down within the same lifeline. Fragments associated with the fragment being dragged should be moved accordingly.

[Tony Chen]

References #536: Main functionality completed

Dragging fragments up and down works correctly.

Implemented DragHandler which is used to handle dragging for MessageCallView, ExecutionStatement, CombinedFragmentView and AssignmentStatementView.

Moved getIndexAfter from MessageViewHandler.java to MessageViewUtil.java.

→ <<cset e2cbc017789d>>

[Tony Chen]

References: #536: Refactoring

• Remove duplicate code in DragHandler.java
• Calls same FragmentController for moving to top spacer of a CombinedFragment
• Put whole notifyChanged body within a runnable in MessageViewView
• Minor refactoring

→ <<cset b07346da5ab3>>

[Tony Chen]

References #536: Remove runnable from notifyChanged

Adding a runnable for the whole notifyChanged block causes an error at line 707 in MessageViewView.removeInteractionFragment when removing a fragment. Runnable is changed back to where Notification.MOVE is handled.

→ <<cset 79eed74a0c1b>>

[Matthias Schoettle]

Tests: Moves moveMessage tests into FragmentsControllerTest.

The FragmentsController is called in all cases now.

refs #536

→ <<cset 4ae09b015e28>>

[Matthias Schoettle]

Tests: Updates tests.

• removes nested behaviour and their tests
• adds some additional tests

refs #536

→ <<cset 54a41ce58f60>>

[Matthias Schoettle]

Merged in Feature/seq_diagram_drag (pull request #140)

Resolves #536: Drag fragments in sequence diagram

Approved-by: Matthias Schoettle

→ <<cset e8a6e6574c16>>