Static variables.

[Shannara]

I am unsure where to put this question, so I placed it here. If its in the wrong section, please let me know

Is it possible to have a static variable in a base class function. And, whenever any derived class calls that function, the static variable is the in all accesses? For example:

Code Select Expand


class BaseClass : CControl
{
declare CreateEx(int  l, int  t, int  w, int  h, int  style, string  title, CWindow  *parent), int;
}

BaseClass :: CreateEx(int  l, int  t, int  w, int  h, int  style, string  title, CWindow  *parent), int
{
static int Count = 1;

CControl!!Create(l, t, w, h, style, Count, title, Parent);

Count += 1;

return Count;
}

Class Class1 : BaseClass
{
// whee?
}

Class Class2 : BaseClass
{
// Whee, oh joy!
}


Now, whenever I want to create a control, the return value should always be 1+ Like

Code Select Expand


Class1.CreateEx(args); // Should return 1
Class2.CreateEx(args); // Should return 2 ... etc


Is this possible? I'm trying to emulate a way that I do not need to worry about ID numbers, while the return is a number. Or maybe even go as far as remove Ids (from the programmer view) entirely. Only dealing with pointers to objects instead Is this possible or could I b grasping at air? It's been a very long week.

[Ionic Wind Support Team]

Looks like it will work.  Although it is the first time I have seen anyone use a static variable like that

[Shannara]

Thanks, I was hoping I am on the right track. My next goal is to then, do a simple wrap on existing controls with a program wide static variable. This would have all controls (on creation) return a unique id. Hopefully, I'll get to the point of releasing just a single include or source file with this, if people are interested in such.

[Mike Stefanik]

Just keep in mind that what you're doing there is not thread safe. You should use the Interlocked APIs to manipulate that variable (eg: InterlockedIncrement, InterlockedDecrement). While you could generally get away with that on a single-core/proc system due to the nature of the x86 architecture (something that I would argue you shouldn't depend on, either), it will definitely bite you on the arse with multi-core/proc systems.

[Shannara]

I currently have a multi core system for development It's working. But then again, I dont use threads in my aurora ports yet Thanks for the tip when I do use threads though.