Need to override drawrect if your UIView is merely a container?
- by Greg Maletic
According to Apple's docs, "Subclasses need not override -[UIView drawRect:] if the subclass is a container for other views."
I have a custom UIView subclass that is indeed merely a container for other views. Yet the contained views aren't getting drawn. Here's the pertinent code that sets up the custom UIView subclass:
- (id)initWithFrame:(CGRect)frame
{
if ((self = [super initWithFrame:frame]))
{
// Consists of both an "on" light and an "off" light. We flick between the two depending upon our state.
self.onLight = [[[LoyaltyCardNumberView alloc] initWithFrame:frame] autorelease];
self.onLight.backgroundColor = [UIColor clearColor];
self.onLight.on = YES;
[self addSubview:self.onLight];
self.offLight = [[[LoyaltyCardNumberView alloc] initWithFrame:frame] autorelease];
self.offLight.backgroundColor = [UIColor clearColor];
self.offLight.on = NO;
[self addSubview:self.offLight];
self.on = NO;
}
return self;
}
When I run the code that displays this custom UIView, nothing shows up. But when I add a drawRect method...
- (void)drawRect:(CGRect)rect
{
[self.onLight drawRect:rect];
[self.offLight drawRect:rect];
}
...the subviews display. (Clearly, this isn't the right way to be doing this, not only because it's contrary to what the docs say, but because it -always- displays both subviews, completely ignoring some other code in my UIView that sets the hidden property of one of the views, it ignores the z-ordering, etc.)
Anyway, the main question: why don't my subviews display when I'm not overriding drawRect:?
Thanks!
