用一个简洁的方式使用UIAlertController。
一个iPhone X的适配让楼主受尽了自定义的苦，使用系统API多好，所以在楼主不懈的努力下，终于和组长达成一致：逐步用系统控件替换代码里面的自定义控件，第一个挨刀的就是 BlockAlertsAnd-ActionSheets,不是楼主不喜欢它或者它写的不好，而是因为这个好替换，可是啊，楼主维护的App代码量大概在100万行左右，全都写成系统的也会吐啊！，下面先介绍下系统的样子。
iOS8.0，苹果开放：UIAlertController 并在之后两个版本放弃了对UIAlertView（9.0）和 UIActionSheet（8.3）的维护。
NS_CLASS_DEPRECATED_IOS(2_0, 9_0, "UIAlertView is deprecated. Use UIAlertController with a preferredStyle of UIAlertControllerStyleAlert instead") __TVOS_PROHIBITED
@interface UIAlertView : UIView
@end
NS_CLASS_DEPRECATED_IOS(2_0, 8_3, "UIActionSheet is deprecated. Use UIAlertController with a preferredStyle of UIAlertControllerStyleActionSheet instead") __TVOS_PROHIBITED
@interface UIActionSheet : UIView
@end
UIAlertController 是UIAlertView &UIActionSheet的合集，通过UIAlertControllerStyle来确定是Alert or ActionSheet
NS_CLASS_AVAILABLE_IOS(8_0) @interface UIAlertController : UIViewController
+ (instancetype)alertControllerWithTitle:(nullable NSString *)title message:(nullable NSString *)message preferredStyle:(UIAlertControllerStyle)preferredStyle;
- (void)addAction:(UIAlertAction *)action;
@property (nonatomic, readonly) NSArray<UIAlertAction *> *actions;
@property (nonatomic, strong, nullable) UIAlertAction *preferredAction NS_AVAILABLE_IOS(9_0);
- (void)addTextFieldWithConfigurationHandler:(void (^ __nullable)(UITextField *textField))configurationHandler;
@property (nullable, nonatomic, readonly) NSArray<UITextField *> *textFields;
@property (nullable, nonatomic, copy) NSString *title;
@property (nullable, nonatomic, copy) NSString *message;
@property (nonatomic, readonly) UIAlertControllerStyle preferredStyle;
@end
UIAlertController 要求初始化的时候就指明类型（preferredStyle 是 readonly），尽管API设计的相当简单，但是用起来总是有点不太舒服，如下：
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:nil message:nil preferredStyle:style];
UIAlertAction *okAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
NSLog(@"OK");
}];
UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"Cancel" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
NSLog(@"OK");
}];
[alertController addAction:okAction];
[alertController addAction:cancelAction];
[self /** self isKindof:UIViewController */presentViewController:alertController animated:YES /** must be YES*/ completion:nil];
楼主想哭，可是自己找的锅，累死也要搞定，所以就着手开始处理，整了3个我就开始觉得不是办法了，想了下，楼主决定动手改造下系统API，楼主不会打自己脸的，所以也不是瞎折腾，也不是自定义，只是改了系统API的调用方式。
其实还是系统的！！！！
其实还是系统的！！！！
其实还是系统的！！！！
好处是你不用太麻烦new一堆东西，也不用一次又一次addAction,只用一个点就可以进行下一步，基本上一气呵成。
下面上一段代码看看怎么使用！
[KDotAlert alert].format(@"Cancel", @"There is Cancel")
.action(@"OK", ^(UIAlertAction * _Nonnull action) {
[self showMore:@"OK"];
}).cancel(@"Cancel", nil).show(self, nil);
至于：[self showMore:@"OK"]; self是安全的，不需要你加weak
看下定义：
NS_CLASS_AVAILABLE_IOS(8_0) @interface KDotAlert : NSObject
@property (nonatomic, strong, readonly) KDotAlertFormat format; // format title & message
@property (nonatomic, strong, readonly) NSString * _Nullable title; // title
@property (nonatomic, strong, readonly) NSString * _Nullable message; // message
@property (nonatomic, assign, readonly) UIAlertControllerStyle preferredStyle; // The style of the alert controller.
@property (nonatomic, strong, readonly) KDotAlertAction action; // Attaches an action object to the alert or action sheet. default style;
@property (nonatomic, strong, readonly) KDotAlertAction cancel; // ... cancel style;
@property (nonatomic, strong, readonly) KDotAlertAction destructive;// ... destructive style;
// The actions that the user can take in response to the alert or action sheet.
@property (nonatomic, strong, readonly) NSArray<UIAlertAction *> * _Nullable actions;
// Make the preferred action for the user to take from an alert.
@property (nonatomic, strong, readonly) KDotAlertPreferred preferred NS_AVAILABLE_IOS(9_0);
@property (nonatomic, strong, readonly) KDotAlertTextField textField; // Adds a text field to an alert;
@property (nonatomic, strong, readonly) NSArray<UITextField *> * _Nullable textFields; // The array of text fields displayed by the alert.
@property (nonatomic, strong, readonly) KDotAlertShow show; // show with viewController
+ (instancetype _Nonnull )alert;
+ (instancetype _Nonnull )actionSheet;
@end
基本上支持了所有系统API...
算了，不吹了,上Github连接;
Crazy凡
2017-11-11
