I'm using a Tree. Each node from the XML of the tree contains a attribute with the name of the class that is to be instantiated when a change event occurs.
The only way for me to use the String typed attribute containing the name of the class to be instantiated, along with a "new" statement would be with a switch statement to test the value of the attribute and then instantiate the appropriate class. I know that I can do that, but that also means that every time a new node is added to the XML for the tree, I also have to modify the source code for the function that handles the change event. If I can create the class from the string name of the class, I can add nodes to the XML without any further maintenance to the switch statement in the source code. --- In flexcoders@yahoogroups.com, "Roger Gonzalez" <[EMAIL PROTECTED]> wrote: > > I'm not sure how you would expect this to work! > > The linker follows the dependency chain of all classes referenced by > your code, and bakes them into the SWF. > > Strings are just strings, it wouldn't make sense for the linker to look > "inside" one. > > Button isn't actually a "built-in" class, there just happens to be a > dependency link to it via Application. > > getClassByName (which is just a wrapper around > ApplicationDomain.getClass, btw) can only see classes that are linked > in. There is no way for it to find some class by string that hasn't > been downloaded to the client - should it email the developer and say > "please compile this and send me a copy"? :-) > > What are you trying to solve such that you can't just "new" your class? > > If you really need total decoupling like this, you might want to look > into building a separately compiled SWF that contains your other > classes, and loading that SWF at runtime. > > -rg > > > -----Original Message----- > > From: flexcoders@yahoogroups.com > > [mailto:[EMAIL PROTECTED] On Behalf Of pwhite40 > > Sent: Saturday, February 18, 2006 9:46 PM > > To: flexcoders@yahoogroups.com > > Subject: [flexcoders] Re: addChild from String > > > > Did you ever get an answer on this? I'm running into the same > > problem with getClassByName(MyCustomClass) blowing up unless > > I create a dummy instance of it first. Even when I do create > > a dummy instance first, it only works the first time I call the > > getClassByName(MyCustomClass) method. After that, I start > > getting "ReferenceError: Error #1065: Variable MyCustomClass > > is not defined" all over again. > > > > Thanks, > > Paul > > > > > > --- In flexcoders@yahoogroups.com, "Brendan Meutzner" > > <bmeutzner@> wrote: > > > > > > Hey Jens, > > > > > > Thanks for the help. It's now working (sort of)... > > > > > > If I create an instance of a built-in class (such as Button), the > > > method below works fine. However, if I try creating a custom Class > > > (eg. MyCustClass which extends from Canvas) like so: > > > > > > import custclasses.MyCustClass; > > > var newComponent:Object = createInstance > > ("custclasses.MyCustClass"); > > > > > > it doesn't work. I get the run-time error message "Variable > > > MyCustClass is not defined". > > > > > > However, if I create a dummy instance of the class in my > > application > > > like so: > > > > > > import custclasses.MyCustClass; > > > var dummyMyCustClass:MyCustClass = new MyCustClass(); > > > > > > and then create another instance using the createInstance method, > > it > > > does work. > > > > > > Ideas? > > > > > > Thanks, > > > > > > Brendan > > > > > > --- In flexcoders@yahoogroups.com, Jens Halm <[EMAIL PROTECTED]> wrote: > > > > > > > > > > > > > Hi All, > > > > > > > > > I'd like to provide a String value which represents the > > DisplayObject > > > > > class I want to create dynamically with addChild. Has anyone > > > > > accomplished this? > > > > > > > > You mean like this? > > > > > > > > public function createInstance (className : String) : Object { > > > > var MyClass : Class = getClassByName(className); > > > > return new MyClass(); > > > > } > > > > > > > > > > > > Btw.: what I really miss is a method createInstance(args : > > Array) in > > > > the Class class, so I could easily provide an arbitrary number of > > > > constructor arguments not known until runtime, like this: > > > > > > > > public function createInstance (className:String, args:Array) : > > Object { > > > > var myClass : Class = getClassByName(className); > > > > return myClass.createInstance(args); } > > > > > > > > Class.createInstance(args:Array) would be the constructor > > equivalent > > > > of Function.apply(scope:Object, args:Array). If I use > > Function.apply > > > > after I created an instance the constructor would be called twice > > > > which would be quite dirty. > > > > > > > > Consider this as a feature request... ;) > > > > > > > > > > > > Jens > > > > www.oregano-server.org > > > > > > > > > > > > > > > > > > > > > -- > > Flexcoders Mailing List > > FAQ: http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt > > Search Archives: > > http://www.mail-archive.com/flexcoders%40yahoogroups.com > > Yahoo! Groups Links > > > > > > > > > > > > > > > -- Flexcoders Mailing List FAQ: http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt Search Archives: http://www.mail-archive.com/flexcoders%40yahoogroups.com Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/flexcoders/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
