GCRect drawing object

Please help.. I want to release a drawing object and or draw over it.. I have a popup with the drawing object in it. I made it by creating a class and then setting the popup to that class. The code in the class is:

- (id)initWithFrameCGRect)frame {
if (self = [super initWithFrame:frame]) {
// Initialization code
}
return self;
}

- (void)drawRectCGRect)rect {

//draw some stuff blah blah blah

}

I pass variables using a global delectation and the

extern float gPhy, gEmo, gInt;

When i release the popup and return change the globals the graph stays the same. Help!