Scrollview doesn't remains on the center indicator - iphone

Question

I am enclosing my sample code herewith for ready reference, please make it in center place, this is what I am facing problem in. It is not stopping on the center indicator.
Note : All button are dynamic and coming from web, but in this sample I made it from a hard coded array. But in original scenerio their count(number of buttons) may change.
- (void)viewDidLoad {
arr = [[NSMutableArray alloc] initWithObjects:#"Test1",#"Test2",#"Test3",#"Test4",#"Test5",nil];
UIImageView *img = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"bg_content_slide.png"]];
img.frame = CGRectMake(0, 20, 320, 85);
img.contentMode = UIViewContentModeScaleAspectFill;
[self.view addSubview:img];
[self setScrollButtons];
[super viewDidLoad];
}
- (void) setScrollButtons
{
UIScrollView *tagScrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 30, 320, 44)];
tagScrollView.backgroundColor = [UIColor clearColor];
[tagScrollView setShowsHorizontalScrollIndicator:NO];
[tagScrollView setShowsVerticalScrollIndicator:NO];
[tagScrollView setCanCancelContentTouches:NO];
tagScrollView.indicatorStyle = UIScrollViewIndicatorStyleBlack;
tagScrollView.clipsToBounds = YES;
tagScrollView.scrollEnabled = YES;
tagScrollView.pagingEnabled = YES;
tagScrollView.bounces = YES;
tagScrollView.tag = 2;
int xaxis = 0;
for (int i = 0; i < [arr count]; i++) {
UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
btn.frame = CGRectMake(xaxis, 0, 160, 44);
//btn.titleLabel.text = [NSString stringWithFormat:#"%#",[arr objectAtIndex:i]];
[btn setTitle:[arr objectAtIndex:i] forState:UIControlStateNormal];
NSLog(#"%#", btn.titleLabel.text);
xaxis += btn.frame.size.width + 20;
[tagScrollView addSubview:btn];
}
[tagScrollView setContentSize:CGSizeMake([arr count] * 200, tagScrollView.frame.size.height)];
[self.view addSubview:tagScrollView];
}
Find code here UnAligned scrollview code

Answer 1

chage ur code with this one
int xaxis = 0;
for (int i = 0; i < [arr count]; i++) {
UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
btn.frame = CGRectMake(320*xaxis+80, 0, 160, 44);
//btn.titleLabel.text = [NSString stringWithFormat:#"%#",[arr objectAtIndex:i]];
[btn setTitle:[arr objectAtIndex:i] forState:UIControlStateNormal];
//[btn setBackgroundImage:[UIImage imageNamed:#"remove_fav.png"] forState:UIControlStateNormal];
NSLog(#"%#", btn.titleLabel.text);
xaxis ++;//= btn.frame.size.width + 40;
[tagScrollView addSubview:btn];
}
[tagScrollView setContentSize:CGSizeMake([arr count] * 320, tagScrollView.frame.size.height)];
[self.view addSubview:tagScrollView];
it will solve ur problem

Answer 2

What you want to achieve is not possible when pagination is enabled as when pagination is enabled the scroll view scroll to its width.So for this what you can do max is add this method
-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
CGPoint offset = scrollView.contentOffset;
int temp = floor(offset.x/160);
[tagScrollView scrollRectToVisible:CGRectMake(temp*160, 0, 320, 44) animated:YES];
}
its working fine for this configuration .......
{
int xaxis = 0;
for (int i = 0; i < [arr count]; i++) {
UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
btn.frame = CGRectMake(160*xaxis+85, 0, 150, 44);
[btn setTitle:[arr objectAtIndex:i] forState:UIControlStateNormal];
NSLog(#"%#", btn.titleLabel.text);
xaxis ++;//= btn.frame.size.width + 40;
[tagScrollView addSubview:btn];
}
[tagScrollView setContentSize:CGSizeMake(160*xaxis+250, tagScrollView.frame.size.height)];
}
and .....
tagScrollView.pagingEnabled = NO;