Subclassing UIActivityIndicator to change the Image - objective-c

Question

This is what I did:
#implementation BGUIActivityIndicator
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
}
[self customInitialize];
return self;
}
-(id)initWithCoder:(NSCoder *)aDecoder
{
self = [super initWithCoder:aDecoder];
[self customInitialize];
return self;
}
-(void)customInitialize
{
UIView * theImageView= [self findASubViewforClass:[UIImageView class]];//
UIImageView * theImageView1 = (UIImageView *) theImageView;
theImageView1.image = [UIImage imageNamed:#"spinner_blue"];
[theImageView1.image saveScreenshot];
while (false) ;
}
/*
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect
{
// Drawing code
}
*/
#end
Everything seems perfect. [theImageView1.image saveScreenshot]; jot down both the old and new view perfectly.
However, nothing changes. Why?
I am not exactly asking how to change the image of UIActivityIndicator. There are tons of it already. I want to use it by subclassing UIActivityIndicator because I think it's the most elegant solution. I can't seem to do that.
In particular, I am asking why my approach, which works for changing background of search controller, for example, doesn't work for this.

Answer 1

According to the UIActivityIndicatorView Class Reference ,there is no way/ chance to change the image through sub-classing.
However you can change its activityIndicatorViewStyle , color of the activity indicator,UIActivityIndicatorStyle etc..
I think, without sub-classing, the class class UIImageView provides a very useful and simple way to implement such a thing. The only thing you have to do is to:
1.Provide a number of images that reflect your indicator animation.
2.Create a new UIImageView instance and set images and animation duration.
3.Position your custom activity indicator within your current view.
SAMPLE CODE:
//Create the first status image and the indicator view
UIImage *statusImage = [UIImage imageNamed:#"status1.png"];
UIImageView *activityImageView = [[UIImageView alloc]
initWithImage:statusImage];
//Add more images which will be used for the animation
activityImageView.animationImages = [NSArray arrayWithObjects:
[UIImage imageNamed:#"status1.png"],
[UIImage imageNamed:#"status2.png"],
[UIImage imageNamed:#"status3.png"],
[UIImage imageNamed:#"status4.png"],
[UIImage imageNamed:#"status5.png"],
[UIImage imageNamed:#"status6.png"],
[UIImage imageNamed:#"status7.png"],
[UIImage imageNamed:#"status8.png"],
nil];
//Set the duration of the animation (play with it
//until it looks nice for you)
activityImageView.animationDuration = 0.8;
//Position the activity image view somewhere in
//the middle of your current view
activityImageView.frame = CGRectMake(
self.view.frame.size.width/2
-statusImage.size.width/2,
self.view.frame.size.height/2
-statusImage.size.height/2,
statusImage.size.width,
statusImage.size.height);
//Start the animation
[activityImageView startAnimating];
//Add your custom activity indicator to your current view
[self.view addSubview:activityImageView];
See the full details Here