YYCategories阅读代码

1NSString+YYAdd

- (BOOL)containsString:(NSString *)string {

    if (string == nil) return NO;

    return [self rangeOfString:string].location != NSNotFound;

}

2NSNumber+YYAdd

+ (NSNumber *)numberWithString:(NSString *)string {
    NSString *str = [[string stringByTrim] lowercaseString];
    if (!str || !str.length) {
        return nil;
    }

    static NSDictionary *dic;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        dic = @{@"true" :   @(YES),
                @"yes" :    @(YES),
                @"false" :  @(NO),
                @"no" :     @(NO),
                @"nil" :    [NSNull null],
                @"null" :   [NSNull null],
                @"<null>" : [NSNull null]};
    });
    NSNumber *num = dic[str];
    if (num) {
        if (num == (id)[NSNull null]) return nil;
        return num;
    }

    // hex number
    int sign = 0;
    if ([str hasPrefix:@"0x"]) sign = 1;
    else if ([str hasPrefix:@"-0x"]) sign = -1;
    if (sign != 0) {
        NSScanner *scan = [NSScanner scannerWithString:str];
        unsigned num = -1;
        BOOL suc = [scan scanHexInt:&num];
        if (suc)
            return [NSNumber numberWithLong:((long)num * sign)];
        else
            return nil;
    }
    // normal number
    NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
    [formatter setNumberStyle:NSNumberFormatterDecimalStyle];
    return [formatter numberFromString:string];
}

3.NSArray+YYAdd

- (id)objectOrNilAtIndex:(NSUInteger)index {
    return index < self.count ? self[index] : nil;
}

- (void)prependObjects:(NSArray *)objects {

    if (!objects) return;

    NSUInteger i = 0;

    for (id obj in objects) {

        [self insertObject:obj atIndex:i++];

    }

}

4.NSTimer+YYAdd

+ (void)_yy_ExecBlock:(NSTimer *)timer {
    if ([timer userInfo]) {
        void (^block)(NSTimer *timer) = (void (^)(NSTimer *timer))[timer userInfo];
        block(timer);
    }
}

+ (NSTimer *)scheduledTimerWithTimeInterval:(NSTimeInterval)seconds block:(void (^)(NSTimer *timer))block repeats:(BOOL)repeats {
    return [NSTimer scheduledTimerWithTimeInterval:seconds target:self selector:@selector(_yy_ExecBlock:) userInfo:[block copy] repeats:repeats];
}

+ (NSTimer *)timerWithTimeInterval:(NSTimeInterval)seconds block:(void (^)(NSTimer *timer))block repeats:(BOOL)repeats {
    return [NSTimer timerWithTimeInterval:seconds target:self selector:@selector(_yy_ExecBlock:) userInfo:[block copy] repeats:repeats];
}

5.NSNotificationCenter+YYAdd

- (void)postNotificationOnMainThreadWithName:(NSString *)name object:(id)object userInfo:(NSDictionary *)userInfo waitUntilDone:(BOOL)wait {
    if (pthread_main_np()) return [self postNotificationName:name object:object userInfo:userInfo];
    NSMutableDictionary *info = [[NSMutableDictionary allocWithZone:nil] initWithCapacity:3];
    if (name) [info setObject:name forKey:@"name"];
    if (object) [info setObject:object forKey:@"object"];
    if (userInfo) [info setObject:userInfo forKey:@"userInfo"];
    [[self class] performSelectorOnMainThread:@selector(_yy_postNotificationName:) withObject:info waitUntilDone:wait];
}

6UIImage+YYAdd

+ (UIImage *)imageWithSize:(CGSize)size drawBlock:(void (^)(CGContextRef context))drawBlock {
    if (!drawBlock) return nil;
    UIGraphicsBeginImageContextWithOptions(size, NO, 0);
    CGContextRef context = UIGraphicsGetCurrentContext();
    if (!context) return nil;
    drawBlock(context);
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return image;
}

7.UIControl+YYAdd

- (NSMutableArray *)_yy_allUIControlBlockTargets {
    NSMutableArray *targets = objc_getAssociatedObject(self, &block_key);
    if (!targets) {
        targets = [NSMutableArray array];
        objc_setAssociatedObject(self, &block_key, targets, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    }
    return targets;
}

- (void)removeAllTargets {
    [[self allTargets] enumerateObjectsUsingBlock: ^(id object, BOOL *stop) {
        [self removeTarget:object action:NULL forControlEvents:UIControlEventAllEvents];
    }];
    [[self _yy_allUIControlBlockTargets] removeAllObjects];
}

8.UIBarButtonItem+YYAdd

#import "UIBarButtonItem+YYAdd.h"
#import "YYCategoriesMacro.h"
#import <objc/runtime.h>

YYSYNTH_DUMMY_CLASS(UIBarButtonItem_YYAdd)

static const int block_key;

@interface _YYUIBarButtonItemBlockTarget : NSObject

@property (nonatomic, copy) void (^block)(id sender);

- (id)initWithBlock:(void (^)(id sender))block;
- (void)invoke:(id)sender;

@end

@implementation _YYUIBarButtonItemBlockTarget

- (id)initWithBlock:(void (^)(id sender))block{
    self = [super init];
    if (self) {
        _block = [block copy];
    }
    return self;
}

- (void)invoke:(id)sender {
    if (self.block) self.block(sender);
}

@property (nullable, nonatomic, copy) void (^actionBlock)(id);

- (void)setActionBlock:(void (^)(id sender))block {
    _YYUIBarButtonItemBlockTarget *target = [[_YYUIBarButtonItemBlockTarget alloc] initWithBlock:block];
    objc_setAssociatedObject(self, &block_key, target, OBJC_ASSOCIATION_RETAIN_NONATOMIC);

    [self setTarget:target];
    [self setAction:@selector(invoke:)];
}

- (void (^)(id)) actionBlock {
    _YYUIBarButtonItemBlockTarget *target = objc_getAssociatedObject(self, &block_key);
    return target.block;
}

9.UIView+YYAdd

- (void)removeAllSubviews {
    //[self.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];
    while (self.subviews.count) {
        [self.subviews.lastObject removeFromSuperview];
    }
}

- (UIViewController *)viewController {
    for (UIView *view = self; view; view = view.superview) {
        UIResponder *nextResponder = [view nextResponder];
        if ([nextResponder isKindOfClass:[UIViewController class]]) {
            return (UIViewController *)nextResponder;
        }
    }
    return nil;
}

10UITableView+YYAdd

- (void)clearSelectedRowsAnimated:(BOOL)animated {
    NSArray *indexs = [self indexPathsForSelectedRows];
    [indexs enumerateObjectsUsingBlock:^(NSIndexPath* path, NSUInteger idx, BOOL *stop) {
        [self deselectRowAtIndexPath:path animated:animated];
    }];
}

11UITextField+YYAdd

- (void)selectAllText {
    UITextRange *range = [self textRangeFromPosition:self.beginningOfDocument toPosition:self.endOfDocument];
    [self setSelectedTextRange:range];
}

- (void)setSelectedRange:(NSRange)range {
    UITextPosition *beginning = self.beginningOfDocument;
    UITextPosition *startPosition = [self positionFromPosition:beginning offset:range.location];
    UITextPosition *endPosition = [self positionFromPosition:beginning offset:NSMaxRange(range)];
    UITextRange *selectionRange = [self textRangeFromPosition:startPosition toPosition:endPosition];
    [self setSelectedTextRange:selectionRange];
}

12

+ (CGFloat)screenScale {
    static CGFloat screenScale = 0.0;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        if ([NSThread isMainThread]) {
            screenScale = [[UIScreen mainScreen] scale];
        } else {
            dispatch_sync(dispatch_get_main_queue(), ^{
                screenScale = [[UIScreen mainScreen] scale];
            });
        }
    });
    return screenScale;
}