I am trying to call a prototyped function from another javascript file but it doesn't seem to work.
BuddyList.js :
function BuddyList(){ .. }
BuddyList.prototype = {
addBuddy : function(buddyName){...}
}
UserOptions.js:
function UserOptions(){
....
BuddyList.addBuddy(username);
}
I get an error stating that BuddyList does not have a method called addBuddy
You don't need to use the .prototype method. Since everything in JS is an object, you can simply extend BuddyList with a new function:
function BuddyList(){
// do whatever
}
BuddyList.addBuddy = function(username){
// do whatever
}
.addBuddy is defined on objects that are constructed from the BuddyList constructor.
You can not call a method of an object like you are trying to do.
You might want to create it as a "static" function
BuddyList.addBuddy = function(buddyName) { ... }
You can then call it from the prototype aswell
BuddyList.prototype.addBuddy = function(buddyName) {
BuddyList.addBuddy.apply(this, arguments)
}
You would need to check for any references to a BuddyList object inside the addBuddy function though.
Remember BuddyList is an object constructor. Calling the addBuddy method on the constructor doesn't make sense. I think you actaully want to do this
buddyList = new BuddyList;
buddyList.append(someBuddy);
In theory if there's only ever one BuddyList then you may want to look for
BuddyList = new BuddyList;
That will overwrite your constructor with an object inherited from the constructor.
You can always call the addBuddy method directly without an object through the prototype as follows:
BuddyList.prototype.addBudy.call(this, someBuddy)
It really depends on what your trying to do.
You can't access a prototype function until and unless you create an instance for the object or function. So instead of
BuddyList.addBuddy(buddyName)
you have to write
new BuddyList().addBuddy(buddyName)
