泛型UIPopoverPresentationController代码

Question

我已经创建了一个通用的UIPopoverPresentationController。我将其放入我的主视图控制器类中，该类具有UIPopoverPresentationControllerDelegate协议。下面是一个如何从主视图控制器调用它的示例：

   [self presentPopoverOnSide:UIPopoverArrowDirectionDown target:viewArrowShouldPointAt storyboardID:@"Popover" popoverSize:CGSizeMake(200, 200)];

下面是代码。这一个例程包含了弹出窗口所需的所有内容。

- (void)presentPopoverOnSide:(UIPopoverArrowDirection)side target:(UIView *)target storyboardID:(NSString *)storyboardID popoverSize:(CGSize)popoverSize {
   // get the popover view controller
   UIStoryboard * storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
   UIViewController * controller = [storyboard instantiateViewControllerWithIdentifier:storyboardID];

   // set the popover view controller parameters
   controller.modalPresentationStyle = UIModalPresentationPopover;
   controller.preferredContentSize = popoverSize;
   [self presentViewController:controller animated:YES completion:nil];

   // set the parameters from the popover itself
   UIPopoverPresentationController * popover = [controller popoverPresentationController];
   popover.delegate = self;   // my view controller is the <UIPopoverPresentationControllerDelegate>

   // define where the popover arrow should point
   popover.permittedArrowDirections = side;
   popover.sourceView = target;
   popover.sourceRect = CGRectMake(0, 0, target.frame.size.width, target.frame.size.height);
}

#pragma Mark ----------------- <UIPopoverPresentationControllerDelegate> methods -------------------

- (void)prepareForPopoverPresentation:(UIPopoverPresentationController *)popoverPresentationController {
   NSLog(@"prepareForPopoverPresentation");
}

- (BOOL)popoverPresentationControllerShouldDismissPopover:(UIPopoverPresentationController *)popoverPresentationController {
   // only called when touchup outside the popover
   NSLog(@"popoverPresentationControllerShouldDismissPopover");
   return YES;
}

- (void)popoverPresentationControllerDidDismissPopover:(UIPopoverPresentationController *)popoverPresentationController {
   // only called when touchup outside the popover
   NSLog(@"popoverPresentationControllerDidDismissPopover");
}

- (void)popoverPresentationController:(UIPopoverPresentationController *)popoverPresentationController willRepositionPopoverToRect:(inout CGRect *)rect inView:(inout UIView *__autoreleasing  _Nonnull *)view {
   NSLog(@"willRepositionPopoverToRect: %@", NSStringFromCGRect(*rect));
}

Answer 1

Swift版本更具体：

func showPathPopover(button: UIButton) {

  let popController = self.storyboard?.instantiateViewController(withIdentifier: "PathPopover") as! PathPopover

  popController.modalPresentationStyle = UIModalPresentationStyle.popover
  popController.popoverPresentationController?.permittedArrowDirections = UIPopoverArrowDirection.any
  popController.popoverPresentationController?.delegate = self
  popController.popoverPresentationController?.sourceView = button
  popController.popoverPresentationController?.sourceRect = button.bounds

  // present the popover
  self.present(popController, animated: true, completion: nil)

}