//创建一个提示框对象
UIAlertController* alert = [UIAlertController alertControllerWithTitle:@"保存状态提示" message:@"保存成功！" preferredStyle:UIAlertControllerStyleAlert];
//创建3个按钮（注：按钮有3种样式）
UIAlertAction* btn1 = [UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:nil];
UIAlertAction* btn2 = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil];
UIAlertAction* btn3 = [UIAlertAction actionWithTitle:@"test" style:UIAlertActionStyleDestructive handler:nil];
//把3个添加到提示框内
[alert addAction : btn1];
[alert addAction : btn2];
[alert. addAction : btn3];
//展示提示框
[self presentViewController:alert animated:YES completion:nil];
