Interesting UIPopoverController in iOS-iPad

 

Effect:

 

To successfully display a UIPopoverController, follow these steps:

Because UIPopoverController directly inherits from NSObject and does not have visualization capabilities, the content above UIPopoverController must be provided by another controller inherited from UIViewController. This is called "content controller"

 

 @interfaceQCLocationButton() <UIPopoverControllerDelegate>        UIPopoverController *  }

 

     QCCityListViewController *cityList =    _popover = [[UIPopoverController alloc] initWithContentViewController:cityList];

 

 

How much screen space is displayed

There are two ways to set the content size:

       _popover.popoverContentSize = CGSizeMake(, );

 

 

From where

You can set the display position in either of the following ways:

This method needs to pass in a CGRecView, that is to say, the CGRect value of the coordinate origin (0, 0) in the upper left corner of the View is relative to the first method:

(2) The second method is:

 

The arrow points to a UIBarButtonItem.

If the screen of the iPad is rotated and the position displayed by UIPopoverController may change, you need to rewrite a method of the controller.

In the preceding method, override the position displayed by UIPopoverController.

                    [_popover presentPopoverFromRect:self.bounds inView:self permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];