A cell can be locked using
cell.locked = true
and unlocked again using
cell.locked = false
Also, cell.is_locked? can be used to test the locked state.
In locked state writing shapes and instances is forbidden
and doing so would raise an exception.
Also, cells cannot be deleted when locked. However, Layout#clear
and Layout#_destroy are always available.
Cells can still be renamed, even if locked.
Matthias Koefferlein
bccf68504f