__null_unspecified属性关键字解决内存泄漏

Analyze静态分析时，经常遇到以下内存泄漏

nil returned from a method that is expected to return a non-null value

原代码示例

@property (nonatomic, strong) UIViewController * liveVC;

- (UIViewController *)liveVC

{

    UINavigationController * aNav = [UIViewController currentTabbarController].selectedViewController;

    for (UIViewController * aVC in aNav.childViewControllers ) {

        if  ([NSStringFromClass(aVC.class) isEqual:@"HZSMeetingOnlineLiveViewController"]) {

            return aVC;

        }

    }

    return nil;

}

解决方式

@property (nonatomic, strong, null_unspecified) UIViewController * liveVC;

原代码示例

- (HZSSameLiveUserModel *)getLiveUserModelWithUserId:(NSString *)userId;

- (HZSSameLiveUserModel *)getLiveUserModelWithUserId:(NSString *)userId//根据用户id获取模型

{

    HZSSameLiveUserModel * aSelectModel;

    for (HZSSameLiveUserModel * aModel in HZSLiveInstance.shareInstance.mLiveWindowList) {

        if ([aModel.selectUserId isEqual:userId]) {

            aSelectModel = aModel;

            break;

        }

    }

    return aSelectModel;

}

解决方式

- (null_unspecified HZSSameLiveUserModel *)getLiveUserModelWithUserId:(NSString *)userId;