ipad - Adding a UIView to a UIViewController's delegate -

i'm selecting cell in uitableviewcontroller (i'll call controller a) presented in popover uiviewcontroller (i'll call b). b set delegate of a, can send messages b when user interacts a. working way want.

i've added code a start loading information coredata when user selects 1 of rows. it's going take little while, want show waiting screen right after user makes selection. in this question addressed how show waiting screen before beginning load data, doesn't seem work when passing messages between controllers.

my waiting screen uiview subclass has uiactivityindicator , uilabel quick message on it. waiting screen @property of b, , call

self.waitingview = [[waitingview alloc] initwithframe:self.view.frame]; [self.waitingview sethidden:yes]; [self.view addsubview:self.waitingview]; 

in b's viewdidload. then, have required @protocol showwaitscreen on a. in a's willselectrowatindexpath, call [self.delegate showwaitscreen];. on b, have

-(void) showwaitscreen {     [self.waitingview sethidden:no]; } 

---

i have put breakpoints in, , calls being made way want, never see wait screen. best guess because a still open popover on b, , preventing changes b's ui. case? if isn't problem, is? in case, how waiting screen show up?

---

edit: information screen layout: b pretty cluttered screen - there plain background (uiview) takes whole screen. on top of uiview, there uiscrollview , uitoolbar - toolbar takes bottom of screen though. in uiscrollview, there 5 uitableviews of different sizes spread out small gaps between. a displayed 1 of tables, , fill top half of screen. waiting screen square half width of screen on each side, , centered on screen. therefore, waiting screen overlap part of a , several of uitableviews on b.