Updating Class List in Class itself

[PakzParticipant]

I created a class called unit which I store in a list. I tried to create a method in this class to update all the units inside this class but I got an error calling this method.

I am not sure how to do something like this. Is it possible if the class is in a list? Do I need to use a stack for this and call the first item from the stack to run this method that updates all?

[JesseParticipant]

I am not sure what you mean. Are you extending the list class with your own method or are you using it some other way?
if you declare the list Global and initialize it only once, it should be possible.

[PakzParticipant]

Here is a example. I want to have methods in the class that update everything. Here below it does not seem to work. I can call the method that should update all the things in the list but it only updates 1.

Monkey

#Import "<std>" #Import "<mojo>" Using std.. Using mojo.. Class unit Field x:Int,y:Int method New(mx:Int,my:Int) Self.x = mx Self.y = my End Method Method moveallright() For Local i:=Eachin myunit i.x+=Rnd(2) Next End Method Method drawall(canvas:Canvas) canvas.Color = Color.White For Local i:=Eachin myunit canvas.DrawCircle(x,y,50) Next End Method End Class Global myunit:List<unit> = New List<unit> Class MyWindow Extends Window Method New() myunit.AddFirst(New unit(10,10)) myunit.AddFirst(New unit(110,110)) End Method Method OnRender( canvas:Canvas ) Override App.RequestRender() ' Activate this method myunit.First.moveallright() myunit.First.drawall(canvas) ' if key escape then quit If Keyboard.KeyReleased(Key.Escape) Then App.Terminate() End Method End Class Function Main() New AppInstance New MyWindow App.Run() End Function

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#Import "<std>" #Import "<mojo>"   Using std.. Using mojo..   Class unit Field x:Int,y:Int method New(mx:Int,my:Int) Self.x = mx Self.y = my End Method Method moveallright() For Local i:=Eachin myunit i.x+=Rnd(2) Next End Method Method drawall(canvas:Canvas) canvas.Color = Color.White For Local i:=Eachin myunit canvas.DrawCircle(x,y,50) Next End Method End Class   Global myunit:List<unit> = New List<unit>   Class MyWindow Extends Window Method New() myunit.AddFirst(New unit(10,10)) myunit.AddFirst(New unit(110,110)) End Method Method OnRender( canvas:Canvas ) Override App.RequestRender() ' Activate this method myunit.First.moveallright() myunit.First.drawall(canvas) ' if key escape then quit If Keyboard.KeyReleased(Key.Escape) Then App.Terminate() End Method End Class   Function Main() New AppInstance New MyWindow App.Run() End Function

[papgarParticipant]

I’m not a OOP master, but I don’t think you want to do it the way you’re doing it.  Looks kinda fishy.

But the issue with your code is it keeps drawing the first circle and none of the others.  Change the line to this so it references the objects in the loop:

Monkey

canvas.DrawCircle(i.x,i.y,50)

1	canvas.DrawCircle(i.x,i.y,50)

[JesseParticipant]

As papgar said and that’s how it’s supposed to be.
also the method moveallright all and drawall should be functions that way there won’t be any confusion on its use. this way you won’t need to use miunit.first.etc.. all you need to do is use unit.moveallright() and unit.drawall()

[PakzParticipant]

Ohh, I did not notice that

Seems to work now.

[PakzParticipant]

I am still a little bit confused on functions and methods. The difference between them.

[JesseParticipant]

treat a function as you would use any independent function. with the exception that if the function is inside a class you can only call it by the class instantiation or by using the class name.functionname(). With method you can only call it if it has been instantiated. and only through it’s instance.

[coconParticipant]

As a sidenote you could do something like this to make the codebase a bit more modular.

Monkey

Class Unit Method Do() End End Class UnitCollection Abstract Global Units:List<Unit> = New List<Unit> Function Init() '...' End Function Update() For Local unit := Eachin Units unit.Do Next End End ' usage: UnitCollection.Init() UnitCollection.Update()

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Class Unit Method Do() End End   Class UnitCollection Abstract Global Units:List<Unit> = New List<Unit> Function Init() '...' End Function Update() For Local unit := Eachin Units unit.Do Next End End   ' usage: UnitCollection.Init() UnitCollection.Update()

[PakzParticipant]

@cocon

That look as how I usually use classes. Only what is the Unitcollection for?

btw – I just discovered a thing with functions and methods that took me a while to fix. I got a error when I had a function inside a class trying to use a list inside the same class. This is not possible. You need to make it a method. Methods have access to the data fields in the class it appears.

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