iOS中UIActionSheet动态添加按钮

#import <UIKit/UIKit.h>
@interface RootViewController : UIViewController
<UIActionSheetDelegate>
@end 

//点击任何处，弹出UIActionSheet
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
  UIActionSheet *sheet=[[UIActionSheet alloc]initWithTitle:@"标题" delegate:self cancelButtonTitle:nil destructiveButtonTitle:nil otherButtonTitles:nil, nil];
  // 逐个添加按钮（比如可以是数组循环）
  [sheet addButtonWithTitle:@"Item A"];
  [sheet addButtonWithTitle:@"Item B"];
  [sheet addButtonWithTitle:@"Item C"];
  // 同时添加一个取消按钮
  [sheet addButtonWithTitle:@"Cancel"];
  sheet.cancelButtonIndex = sheet.numberOfButtons-1;
  [sheet showInView:self.view];
}