calling a method from a different class's view

rubyonrails-talk
1

Hi all,

I have two classes: a player class and a game class. Each game has two player IDs. I would like the game show view to be able to display each player's full name via a method, as follows: <%=h Player.get_player_name(@game.player2) %>

Here is the method definition in my players controller:   def get_player_name(playerID)     @player = Player.find(playerID)     @playerName = @player.firstName + " " + @player.lastName   end

When I try to view the page, I get the error: Showing app/views/games/show.html.erb where line #8 raised:

undefined method `get_player_name' for #<Class:0x252de68>

Extracted source (around line #8):

5: 6: <p> 7: <b>Player2:</b> 8: <%=h Player.get_player_name(@game.player2) %> 9: </p> 10: 11: <p>

I can call the get_player_name method from a player view. Clearly I don't understand something about how rails does its scoping, but I am not sure where to look. For instance, I don't see anything in my Learning Rails book that might explain how this works.

My question is: where can I put my get_player_name method so that it can be accessed by other classes as well?

I am actually surprised that I can't access the method, because the following does work from within my game show view: <%=h Player.find(@game.player1).firstName + " " + Player.find(@game.player1).lastName %>

Thanks, Stu

2

This is more of a ruby / object oriented programming fundamentals question. You say that you defined this method in the players controller, but you're attempting to call it as if it was a class method on Player. If you wanted to make this work then you'd want to actually make it a class method on Player, ie you would write

def.self.get_player_name(...) ... end

in your player class.

That would be slightly odd design though. A more railsy way of doing it would be for player2 to be an association and to define a full name method on Player ie

def full_name firstName + lastName end

and then your view would look like <%= h @game.player2.full_name %>

It's also convention that attribute names be underscored (ie first_name rather than firstName)

Fred

3

The other convention I think is important here is that your "getters" do not start with "get" like they do in Java. You generally just put the attribute name. Because Ruby doesn't require parentheses after methods, you can just say "player.full_name" instead of "player.getFullName()" like you would in Java. It's a more concise and clear grammar.