Vivek Sehrawat Vivek Sehrawat - 4 months ago 39
iOS Question

How can i change the page on clicking the dots of UIPageControl

Here I have a pagecontrol which works good but on clicking on dot it doesn't change the page so please help in the function of changepage:

- (void)viewDidLoad {
scrollView=[[UIScrollView alloc]initWithFrame:CGRectMake(0, 0, 320, 420)];
scrollView.delegate = self;
[self.scrollView setBackgroundColor:[UIColor whiteColor]];
[scrollView setCanCancelContentTouches:NO];
scrollView.indicatorStyle = UIScrollViewIndicatorStyleWhite;
scrollView.clipsToBounds = YES;
scrollView.scrollEnabled = YES;
[scrollView setShowsHorizontalScrollIndicator:NO];
scrollView.pagingEnabled = YES;
[self.view addSubview:scrollView];
pageControl=[[UIPageControl alloc]initWithFrame:CGRectMake(0, 420, 320, 40)];
[pageControl addTarget:self action:@selector(changepage:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:pageControl];

UIView *blueView = [[UIView alloc] init];
blueView.frame = CGRectMake(0, 0, 640, 480);
blueView.backgroundColor = [UIColor whiteColor];
[scrollView addSubview:blueView];
self.pageControl.numberOfPages = 2;
[scrollView setContentSize:CGSizeMake(640, 0)];
}

-(void)changepage:(id)sender
{
int page = pageControl.currentPage;
if (page < 0)
return;
if (page >= 2)
return;
CGRect frame = scrollView.frame;
frame.origin.x = frame.size.width * page;
frame.origin.y = 0;
[scrollView scrollRectToVisible:frame animated:YES];

}

- (void)scrollViewDidScroll:(UIScrollView *)_scrollView
{
if (pageControlIsChangingPage)
return;
CGFloat pageWidth = _scrollView.frame.size.width;
int page = floor((_scrollView.contentOffset.x - pageWidth / 2) / pageWidth) + 1;
pageControl.currentPage = page;
}

Answer

You can create one event change page:

- (IBAction)changePage:(id)sender {
    UIPageControl *pager=sender;
    int page = pager.currentPage;
    CGRect frame = imageGrid_scrollView.frame;
    frame.origin.x = frame.size.width * page;
    frame.origin.y = 0;
    [imageGrid_scrollView scrollRectToVisible:frame animated:YES];
}

Bind it to Pagecontrol's value changed event.