Le 22 mars 07 à 17:46 Soir, [EMAIL PROTECTED] a écrit: > On Mar 22, 2007, at 15:29 UTC, Arnaud Nicolet wrote: > >> I'm also interested in this technique, but I know nothing about >> interfaces (I know about classes, though). I'd like to understand >> this (actually I was not even able to create a class that has >> "actionNotificationReceiver" among its interfaces). > > Why? What happened when you tried? If you typed it directly into the > Interfaces property, are you sure you spelled it correctly?
So, I made a new class, copied "actionNotificationReceiver" from the web page and pasted it in the "Interfaces" property and opened the class. It was simply empty. >> Can you recommend a way to learn interfaces directly from RB? > > They're not tricky; let's just cover them here. > > An Interface is like a class, except that it only defines the > prototypes (name, parameters, and return type) of its methods. It > doesn't contain any code or properties, and you can't instantiate it > directly (i.e. you can't use it with "New"). > > But other classes can "implement" an interface, which means that they > declare it in their Interfaces list, and they implement each of the > methods that interface defines. The easiest way to implement an > interface is to control-click on your class in the Project tab, choose > "Implement Interface..." from the contextual menu, and then check off > the interface(s) you want to implement in the list that appears. This > will also add the methods of that interface to your class, so all you > have to do is fill in the code. > > Interfaces are very handy because, while a class can have only one > superclass, it can implement as many interfaces as it likes. Even > windows can implement interfaces. And an interface is a type, just > like a class; you can declare variables or parameters of that type, > and > you can test for an interface with IsA. > > I won't go into all the deep reasons why single inheritance but > multiple interfaces is great language design, but suffice to say that > it is very convenient once you get the hang of it. Thank you so much! I'll try that right now. _______________________________________________ Unsubscribe or switch delivery mode: <http://www.realsoftware.com/support/listmanager/> Search the archives: <http://support.realsoftware.com/listarchives/lists.html>
