如何在 iPhone、iOS 8 上为弹出框设置动画

Question

我在按钮单击时出现了一个弹出框，但它没有动画。我希望它从零大小开始，并成长为类似于 facebooks 在帖子上的胡萝卜动作的正确大小。非常感谢任何帮助。代码如下：

@IBAction func button(sender: AnyObject) {
    let popover = PopoverController()
    popover.modalPresentationStyle = .Popover
    popover.preferredContentSize = CGSizeMake(UIScreen.mainScreen().bounds.width, 100)

    let popoverPresentationController = popover.popoverPresentationController
    popoverPresentationController?.permittedArrowDirections = UIPopoverArrowDirection.Up
    popoverPresentationController?.delegate = self
    popoverPresentationController?.sourceView = sender as UIView
    popoverPresentationController?.sourceRect = sender.bounds

    self.presentViewController(popover, animated: true, completion: nil)
}


func adaptivePresentationStyleForPresentationController(controller: UIPresentationController!) -> UIModalPresentationStyle {
        return UIModalPresentationStyle.None
}

Answer 1

你可以试试

popoverPresentationController?.modalTransitionStyle = .crossDissolve 

就在演示之前。