Confused about Navigability and Direction

[ocroquette]

Hi

I am pretty confused about navigability and direction as available in EA.
In the EA GUI, there are 3 relevant places:

• 1. Association Properties / Direction
  
• 2. Association Properties / XXX role / navigability
  
• 3. Right click on association name / Direction
  

3. is clear, it's just the direction in which to read the association('s name), but I am confused with 1. and 2.

EA seems to use both of these settings to show or not the arrows at the ends of an association, in an logical OR fashion. Is that right?
What is the semantic of (Direction=Bi) and (Navigabilities=Non)?
or (Direction=Source-Dest) and (Navigabilities=Yes for the target role)?
When to use direction and when to use navigation?

I found the following discussions, but they didn't help much:
- http://www.sparxsystems.com/cgi-bin/yabb/YaBB.pl?board=UMLPRO;action=display;num=1167812511

- http://www.sparxsystems.com/cgi-bin/yabb/YaBB.pl?board=suggestions;action=display;num=1111705430




Thanks for your help.

[ocroquette]

OK, I have just realized that Direction and Navigabilities are linked.
If you change one, it changes the other.
Not very intuitive.

[Paolo F Cantoni]

OK, I have just realized that Direction and Navigabilities are linked.
If you change one, it changes the other.
Not very intuitive.

Not surprising - since they shouldn't be...

Paolo