CCAdvancedMenu boundaryRect - ios

Question

Hoping someone can help me with this... I'm following examples seen here for CCMenuAdvanced but am ending up with a weird result, I see my menu and it scrolls but using the boundaryRect property I can't seem to get it to hide part of the menu and show what I want.
Here's my code:
// Setup Menu Alignment
[menuA alignItemsVerticallyWithPadding:0 bottomToTop:NO]; //< also sets contentSize and keyBindings on Mac
menuA.isRelativeAnchorPoint = YES;
menuA.boundaryRect = CGRectMake(0, 100, 230, 200);
[menuA fixPosition];
[self addChild:menuA];
I'm able to scroll and view my entire list which is good, but I can't set up an area to view only part of the menu at a time, which is what boundaryRect should do. Has anyone used this before and can give me some advice?!?
Thanks!

Answer 1

Well, not from the same class, but a home grown scrolling menu. I use the visibility and transparencies of the menuItems themselves. When scrolling up, if a menu label approaches the rectangle's edge, i start fading it out to 0. When the anchor point of the menuItem is outside the rectangle, i set its visibility to NO (thus cant be clicked). Same going down. Clamping is tricky. You have to set these properties when the list of menuItems changes, in case it grows shorter than the height of the boundary rectangle, or grows again greater than the rectangle. Something like this (edited, not actual code ... dont know if it compiles :) ):
-(void) fixMenuItemOpacity:(CCMenuItemLabel*) mi{
float theY = mi.position.y ;
if (fadeOutZoneHeight_<4.0f) {
if (theY> self.boundaryRect.origin.y+self.boundaryRect.size.height/2 - fadeOutZoneHeight_) {
mi.visible=NO;
} else if( theY < self.boundaryRect.origin.y-self.boundaryRect.size.height/2 + fadeOutZoneHeight_) {
mi.visible=NO;
} else {
mi.visible=YES;
}
return;
}
float delta;
float percentOpacity;
float topWindow;
float bottomWindow;
float top;
float bottom;
/*
not visible
--------------------------- top
visible, variable opacity
--------------------------- top window
opacity 100%
-------------------------- bottomWindow
visible, variable opacity
------------------------- bottom
*/
top = self.boundaryRect.origin.y + self.boundaryRect.size.height/2;
topWindow = top - fadeOutZoneHeight_;
bottom = self.boundaryRect.origin.y - self.boundaryRect.size.height/2;
bottomWindow=bottom+ fadeOutZoneHeight_;
if (theY> top ) {
mi.visible=NO;
} else if ( (theY > topWindow) && (theY < top)) {
mi.visible=YES;
delta = abs((int)top - (int)theY);
percentOpacity=delta/fadeOutZoneHeight_;
mi.opacity=(GLubyte )(255.0f*percentOpacity);
} else if( (theY <= topWindow ) && (theY >= bottomWindow ) ){
mi.opacity=255;
mi.visible=YES;
} else if ( (theY < bottomWindow) && (theY >= bottom) ){
mi.visible=YES;
delta= abs((int)bottom - (int)theY);
percentOpacity = delta/fadeOutZoneHeight_;
mi.opacity=(GLubyte ) (255.0*percentOpacity);
} else {
mi.visible=NO;
}
}