UIActionSheet *sheet = [[UIActionSheet alloc] initWithTitle:@"打开图片" delegate:self cancelButtonTitle:@"关闭"destructiveButtonTitle:nil otherButtonTitles:@"相册", @"相机", nil];
//cancelButtonTitle destructiveButtonTitle是系统自动的两项。
//otherButtonTitles是自己定义的项，注意，最后一个参数要是nil。
sheet.actionSheetStyle =UIActionSheetStyleBlackOpaque;//UIActionSheetStyleBlackTranslucentactionsheet的样式,枚举值;
[sheet showInView:self.view];//在当前view显示Action sheet
原文：http://www.cnblogs.com/tian-sun/p/4500904.html