一些不常用的方法

忽略警告

忽略可能存在内存泄漏警告

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
          [moduleInstance performSelector:selector
                               withObject:[UPContext sharedInstance]];
#pragma clang diagnostic pop
      }

支持http协议

ios9开始苹果安全会自动先知http网址的访问，如果想开放此访问，需要在info.plist中进行修改。
添加App Transport Security Setting，其中继续添加Allow Arbitrary Loads，设置为Yes。

宏定义中"##","@#"

例如DKNightVersionManager中宏定义语法
#define DKColorPickerWithKey(key) [[DKColorTable sharedColorTable] pickerWithKey:@#key]
使用时：
self.dk_backgroundColorPicker = DKColorPickerWithKey(backgroundColor);
backgroundColor本身不是字符串，可在宏定义中经过@#字符，其中#为字符串化的意思，转换为@"backgroundColor"字符串。
此为C中语法。
可参考如下：

#define f(a,b) a##b             //##被称为连接符（concatenation），把宏参数与之前的token(参数／字符串空格等)连接起来。
#define g(a) #a                 //#:把宏参数转换为字符串。不管该参数宏什么，即“原貌”用字符串显示出来

音频后台播放

// Apps using this category don't mute when the phone's mute button is turned on, but play sound when the phone is silent
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback withOptions:AVAudioSessionCategoryOptionAllowBluetooth error:nil];
[[AVAudioSession sharedInstance] setActive:YES error:nil];

渐变色

    CAGradientLayer *graLayer = [CAGradientLayer layer];
    graLayer.frame = CGRectMake(100, 100, 200, 200);
    graLayer.colors = @[
        (__bridge id)[UIColor redColor].CGColor,
        (__bridge id)[UIColor yellowColor].CGColor
    ];
//    graLayer.locations = @[@0, @0.2];
    graLayer.startPoint = CGPointMake(0, 0);
    graLayer.endPoint = CGPointMake(1, 1);
    [self.view.layer addSublayer:graLayer];

旋转适配

- (void)viewSafeAreaInsetsDidChange{
    [super viewSafeAreaInsetsDidChange];
    
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 110000
    if (@available(iOS 11.0, *)){
           
        if (deviceOrientationisLandscape()) {
            [self.commentMoreBtn mas_updateConstraints:^(MASConstraintMaker *make) {
                make.right.mas_equalTo(self.view.mas_safeAreaLayoutGuideRight).offset(-15);
            }];
        }else
        {
            [self.commentMoreBtn mas_updateConstraints:^(MASConstraintMaker *make) {
                make.right.mas_equalTo(-15);
            }];
        }
    }
#endif
}

系统下拉手势冲突问题

- (UIRectEdge)preferredScreenEdgesDeferringSystemGestures {
    return UIRectEdgeAll;
}