Scrolling to specific page using pageControl and ScrollView ios - ios

Question

I know this question has been asked earlier but i am not getting any specific answer to my problem. I am using page control and scrollView to add view controllers and then showing all the pages using swipe. I need to redirect to a particular page on button click. I tried scrollView SetcontentOffet and every other possiblities.
-(void)ScrollToPage:(int)page
{
UIViewController *controller = [self.childViewControllers objectAtIndex:page];
if (controller.view.superview == nil)
{
CGRect frame = self.scrollView.frame;
if (frame.size.width == 0)
{
frame.size.width = self.view.frame.size.width;
frame.size.height = self.view.frame.size.height;
}
frame.origin.x = frame.size.width * page;
frame.origin.y = 0;
controller.view.frame = frame;
[scrollView setContentOffset:CGPointMake(frame.origin.x, frame.origin.y) animated:YES];
self.pageControl.currentPage = page;
[self centerScrollViewContents];
[self.scrollView setContentOffset:CGPointMake(frame.origin.x, frame.origin.y)];
[self.scrollView scrollRectToVisible:frame animated:YES];
[self.scrollView addSubview:controller.view];
}
}

Answer 1

I assume that your pages are using your device width closely. Just follow the below steps.
- (void)viewWillAppear:(BOOL)animated {
self.myCurrentPage = 0;
[self setScrollViewPages];
self.scrollView.delegate = self;
}
- (void)setScrollViewPages {
for (int i = 0; i < numberOfPages; i++) {
UIView *myPageView = [[UIView alloc]initWithFrame:(CGRect) {self.view.frame.size.width * i
+ 10.0f,10.0f,self.view.frame.size.width - 20.0f , self.scrollView.frame.size.height-20.0f}];
myPageView.backgroundColor = [UIColor greenColor];
[self.scrollView addSubview:myPageView];
}
}
On Button Clicked
- (IBAction)buttonClicked:(id)sender {
//Pass the requried page, by default I'm passing 4
self.myCurrentPage = 4;
[self updateMyScrollView];
}
And the respective scroll view setting is
- (void)updateMyScrollView {
[self.scrollView setContentOffset:CGPointMake(self.view.frame.size.width *self.myCurrentPage, 0) animated:YES];
self.pageControl.currentPage = self.myCurrentPage;
}
Additionally, your scrollview delegate would be like this...
- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset{
int pageWidth = self.view.frame.size.width ;
int pageX = self.myCurrentPage*pageWidth - scrollView.contentInset.left;
if (targetContentOffset->x<pageX) {
if (self.myCurrentPage>0) {
self.myCurrentPage--;
}
}
else if(targetContentOffset->x>pageX){
if (self.myCurrentPage < numerOfPages) {
self.myCurrentPage++;
}
}
targetContentOffset->x = self.myCurrentPage*pageWidth-scrollView.contentInset.left;
DLog(#"%ld %d", (long)self.myCurrentPage, (int)targetContentOffset->x);
self.pageControl.currentPage = self.myCurrentPage;
}
Hope this helps....