Ipad 在iOS8中更改操作表弹出箭头

我正在使用

UIAlertController

。但在iOS 8的iPad上，操作表显示的是popover arrow。有没有办法把箭藏起来

这是我的密码：

UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"this is alert controller" message:@"yeah" preferredStyle:UIAlertControllerStyleActionSheet];

            UIAlertAction *cancelAction = [UIAlertAction
                                           actionWithTitle:NSLocalizedString(@"Cancel", @"Cancel action")
                                           style:UIAlertActionStyleCancel
                                           handler:^(UIAlertAction *action)
                                           {
                                               NSLog(@"Cancel action");
                                           }];

            UIAlertAction *okAction = [UIAlertAction
                                       actionWithTitle:NSLocalizedString(@"OK", @"OK action")
                                       style:UIAlertActionStyleDefault
                                       handler:^(UIAlertAction *action)
                                       {
                                           NSLog(@"OK action");
                                       }];

            UIAlertAction *deleteAction = [UIAlertAction
                                           actionWithTitle:NSLocalizedString(@"Delete", @"Delete action")
                                           style:UIAlertActionStyleDestructive
                                           handler:^(UIAlertAction *action) {
                                               NSLog(@"Delete action");
                                           }];

            [alertController addAction:cancelAction];
            [alertController addAction:okAction];
            [alertController addAction:deleteAction];

            UIPopoverPresentationController *popover = alertController.popoverPresentationController;
            if (popover) {
                popover.sourceView = self.view;
                popover.sourceRect = self.view.bounds;
                popover.permittedArrowDirections = UIPopoverArrowDirectionUnknown;
            }
            [self presentViewController:alertController animated:YES completion:nil];

---

您使用UIPopoverPresentationController显示警报时走错了方向。你只是不需要那些被剪掉的代码

UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"this is alert controller" message:@"yeah" preferredStyle:UIAlertControllerStyleActionSheet];

        UIAlertAction *cancelAction = [UIAlertAction
                                       actionWithTitle:NSLocalizedString(@"Cancel", @"Cancel action")
                                       style:UIAlertActionStyleCancel
                                       handler:^(UIAlertAction *action)
                                       {
                                           NSLog(@"Cancel action");
                                       }];

        UIAlertAction *okAction = [UIAlertAction
                                   actionWithTitle:NSLocalizedString(@"OK", @"OK action")
                                   style:UIAlertActionStyleDefault
                                   handler:^(UIAlertAction *action)
                                   {
                                       NSLog(@"OK action");
                                   }];

        UIAlertAction *deleteAction = [UIAlertAction
                                       actionWithTitle:NSLocalizedString(@"Delete", @"Delete action")
                                       style:UIAlertActionStyleDestructive
                                       handler:^(UIAlertAction *action) {
                                           NSLog(@"Delete action");
                                       }];

        [alertController addAction:cancelAction];
        [alertController addAction:okAction];
        [alertController addAction:deleteAction];

       [self presentViewController:alertController animated:YES completion:nil];

---

解决方案：

使用下一行从行动表中删除箭头

[yourAlertController.popoverPresentationController setPermittedArrowDirections:0];

样本

UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Test Action Sheet" message:@"Message" preferredStyle:UIAlertControllerStyleActionSheet];

    UIAlertAction *cancelAction = [UIAlertAction
                                   actionWithTitle:@"Cancel"
                                   style:UIAlertActionStyleDestructive
                                   handler:^(UIAlertAction *action)
                                   {
                                       NSLog(@"Cancel action");
                                   }];

    UIAlertAction *okAction = [UIAlertAction
                               actionWithTitle:@"Ok"
                               style:UIAlertActionStyleDefault
                               handler:^(UIAlertAction *action)
                               {
                                   NSLog(@"OK action");
                               }];
    UIAlertAction *otherAction = [UIAlertAction
                               actionWithTitle:@"Other"
                               style:UIAlertActionStyleDefault
                               handler:^(UIAlertAction *action)
                               {
                                   NSLog(@"Otheraction");
                               }];

    [alertController addAction:okAction];
    [alertController addAction:otherAction];
    [alertController addAction:cancelAction];


    // Remove arrow from action sheet.
    [alertController.popoverPresentationController setPermittedArrowDirections:0];

    //For set action sheet to middle of view.
    alertController.popoverPresentationController.sourceView = self.view;
    alertController.popoverPresentationController.sourceRect = self.view.bounds;

    [self presentViewController:alertController animated:YES completion:nil];

输出

---

杰金的回答，用Swift：

popoverController.permittedArrowDirections = UIPopoverArrowDirection(rawValue: 0)

---

如果您有导航/状态栏，则所选答案不会使警报居中。要使警报控制器精确居中，请执行以下操作：

alertController.popoverPresentationController.sourceRect = [self sourceRectForCenteredAlertController];
alertController.popoverPresentationController.sourceView = self.view;
alertController.popoverPresentationController.permittedArrowDirections = 0;

使用方便的方法：

- (CGRect)sourceRectForCenteredAlertController
{
    CGRect sourceRect = CGRectZero;
    sourceRect.origin.x = CGRectGetMidX(self.view.bounds)-self.view.frame.origin.x/2.0;
    sourceRect.origin.y = CGRectGetMidY(self.view.bounds)-self.view.frame.origin.y/2.0;
    return sourceRect;
}

此外，如果旋转视图，警报控制器不会保持居中。要使警报控制器居中，需要在旋转后更新sourceRect。例如：

- (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation
{
    // Check if your alert controller is still being presented
    if (alertController.presentingViewController) {
        alertController.popoverPresentationController.sourceRect = [self sourceRectForCenteredAlertController];
    }
}

或者，如果不想使用旋转事件，可以使用

popopoverpresentationcontroller

delegate方法重新定位popover：

- (void)popoverPresentationController:(UIPopoverPresentationController *)popoverPresentationController willRepositionPopoverToRect:(inout CGRect *)rect inView:(inout UIView *__autoreleasing  _Nonnull *)view
{ 
    // Re-center with new rect
}

---

使用[alertControllerActionSheet.popoverPresentationController设置许可证行方向：0]；rect.orign.x=。。。和.y==。。。不需要。