如何将UIPageControl放在Swift的中心

Question

I do this tutorial http://swiftiostutorials.com/ios-tutorial-using-uipageviewcontroller-create-content-slider-objective-cswift/ there use standard page control on the bot, I want to do it in the center. I create new PageControl and can't to join it to UIPageViewController to swipe with

Answer 1

I was able to make my UIPageControl stay centered on a view using View Autoresizing: Flexible Bottom Margin (I was particularly having issues with its position when i rotated the screen - it would become off center after rotation. Before rotation, the frame values I was using would make it initially centered, then rotation messed that up.)

If you are using storyboard, you would just need to set the value for AutoResizing Masks to Flexible Bottom Margin in the attributes inspector when you have the page control highlighted on the storyboard.

If doing programmatically, you should add this line along with the rest of your code for your UIPageControl - it might be in ViewDidLoad, or in a different function that is used to create the page control.

pageControl.autoresizingMask = UIViewAutoresizing.FlexibleBottomMargin

Don;t forget that you will also need to make sure the frame values you give the PageControl object place it in approximately correct area of the view too. A great way to do this is to use calculated percentages of screen or view width and height. Below is the framing i used as an example. Note that the variables screenWidth and screenHeight were assigned values of UIScreen.mainScreen().bounds.size.width and UIScreen.mainScreen().bounds.size.height , so they represent the height and width of my screen. If you place the PageControl inside a view, then use the view height and width instead.

pageControl.frame = CGRect(x: screenWidth * 0.25, y: screenHeight-20, width: screenWidth* 0.5, height: 20)

Answer 2

To customize you need to make your own page controller by yourself, with delegations. Or hide native panel and realise yours through calculations.

Reference to code project of PageViewController: https://github.com/dimpiax/UIPageViewControllerScrolling/tree/master/UIPageViewControllerScrolling