1，下面创建一个操作表（或叫底部警告框）并弹出显示
（注：自IOS8起，建议使用UIAlertController代替UIActionSheet。）
import UIKit
class ViewController: UIViewController,UIActionSheetDelegate {
override func viewDidLoad() {
super.viewDidLoad()
let actionSheet=UIActionSheet()
//actionSheet.title = "请选择操作"
actionSheet.addButtonWithTitle("取消")
actionSheet.addButtonWithTitle("动作1")
actionSheet.addButtonWithTitle("动作2")
actionSheet.cancelButtonIndex=0
actionSheet.delegate=self
actionSheet.showInView(self.view);
}
func actionSheet(actionSheet: UIActionSheet, didDismissWithButtonIndex buttonIndex: Int) {
print("点击了："+actionSheet.buttonTitleAtIndex(buttonIndex)!)
}
}
2，在一般情况下，工具条，或标签条中显示的调用方式是不一样的
actionSheet.showInView(self.view); //一般情况
actionSheet.showFromToolbar(self.navigationController.toolbar) //工具条的情况下
actionSheet.showFromTabBar(self.tabBar) //标签条的情况下
