在iOS9上进行演示之前,UIPopoverPresentationController应该设置一个非零的sourceView或barButtonItem

我正在尝试使用自定义UIPopoverPresentationController类来显示弹出窗口.但它崩溃了错误() should have a non-nil sourceView or barButtonItem set before the presentation occurs.下面是我发生崩溃的按钮单击代码.

- (IBAction)showPopup:(UIButton *)sender {
ViewController *cOntentViewController= [[ViewController alloc] init];

    contentViewController.preferredCOntentSize= CGSizeMake(200, 200);
    contentViewController.modalPresentatiOnStyle= UIModalPresentationPopover;
    myPopoverController *popOver = [[myPopoverController alloc]initWithPresentedViewController:contentViewController presentingViewController:self andTintColor:[UIColor lightGrayColor]];

    popOver.delegate = self;
    popOver.permittedArrowDirectiOns= UIPopoverArrowDirectionUp;
    popOver.sourceRect = sender.frame;
    popOver.sourceView = self.view;
    [self presentViewController:contentViewController animated: YES completion: nil];
}

下面是我的自定义UIPopoverPresentationController的样子示例

myPopoverController.h file

@interface myPopoverController : UIPopoverPresentationController

@property (readonly) UIColor *tintColor;


-(instancetype)initWithPresentedViewController:(UIViewController *)presentedViewController presentingViewController:(UIViewController *)presentingViewController andTintColor:(UIColor *)aTintColor;

@end


myPopoverController.m file

//Some code for UIPopoverBackgroundView

-(instancetype)initWithPresentedViewController:(UIViewController *)presentedViewController presentingViewController:(UIViewController *)presentingViewController
{

    self = [self initWithPresentedViewController:presentedViewController presentingViewController:presentingViewController andTintColor: [UIColor redColor]];

    return self;
}


-(instancetype)initWithPresentedViewController:(UIViewController *)presentedViewController presentingViewController:(UIViewController *)presentingViewController andTintColor:(UIColor *)aTintColor
{

    self = [super initWithPresentedViewController:presentedViewController presentingViewController:presentingViewController];

    if (!self) {
        return nil;
    }

    [super setPopoverBackgroundViewClass: [myPopoverControllerBackgroundView class]];
    tintColor = aTintColor;


    return self;
}

我没有barbutton但是我正在设置sourceView.我在这里做错了吗？感谢您的帮助

您也可以创建这样的popover演示控制器,它可能会起作用

- (IBAction)showPopup:(UIButton *)sender {

ViewController *cOntentViewController= [[ViewController alloc] init];
    contentViewController.preferredCOntentSize= CGSizeMake(200, 200);
    contentViewController.modalPresentatiOnStyle= UIModalPresentationPopover;

UIPopoverPresentationController *popoverpresentatiOnController= contentViewController.popoverPresentationController;
    popoverpresentationController.delegate = self;
    popoverpresentationController.permittedArrowDirectiOns= UIPopoverArrowDirectionUp;
    popoverpresentationController.sourceRect = sender.bounds;
    popoverpresentationController.sourceView = sender;
    [self presentViewController:contentViewController animated: YES completion: nil];
}