iOS实用小方法集锦（二）_ios downloadmodelifneededwithconditions-优快云博客

本文链接：https://blog.youkuaiyun.com/cishengchangan/article/details/51424789

本文探讨了UINavigationController中标题偏移的问题解决方法，通过修改backBarButtonItem的样式来调整。此外，还介绍了如何计算倒计时时间，包括天数、小时、分钟和秒的转换。文章涵盖了Objective-C代码优化技巧，如使用宏定义改进NSLog的使用，以及从字典转换为Model的属性设置技巧。

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UINavigationController之标题歪了

NSArray *VCArray = [self.navigationController viewControllers];
    
    long beforeVCNumber = [VCArray indexOfObject:self] - 1;
    UIViewController *beforeVC;
    if (beforeVCNumber >= 0) {
        beforeVC = [VCArray objectAtIndex:beforeVCNumber];
        beforeVC.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc]initWithTitle:@""style:UIBarButtonItemStylePlain                                             target:self action:nil];
}

倒计时时间计算

		long long day = countdown / (24*60*60);
        long long hour = (countdown % (24*60*60))/(60*60);
        long long minute = (countdown - (24*60*60)*day-hour*60*60)/60;
        long long second = countdown - 24*60*60*day-hour*60*60-minute*60;

打印方法优化

#define NSLog(FORMAT, ...) fprintf(stderr, "位置：%s %d行 \n内容：%s\n\n", [[[NSString stringWithUTF8String: __FILE__] lastPathComponent] UTF8String], __LINE__, [[NSString stringWithFormat: FORMAT, ## __VA_ARGS__] UTF8String])

字典转model，设置model属性快捷输入@property

+ (void)propertyCodeWithDictinoray:(NSDictionary *)dic{
    NSMutableString *muStr = [NSMutableString string];
    [dic enumerateKeysAndObjectsUsingBlock:^(id  _Nonnull key, id  _Nonnull obj, BOOL * _Nonnull stop) {
        NSString *str;
        NSLog(@"%@",[obj class]);
        if ([obj isKindOfClass:NSClassFromString(@"__NSCFString")] || [obj isKindOfClass:NSClassFromString(@"NSTaggedPointerString")] || [obj isKindOfClass:NSClassFromString(@"__NSCFConstantString")]) {
            str = [NSString stringWithFormat:@"@property (nonatomic, copy) NSString *%@;",key];
        }
        if ([obj isKindOfClass:NSClassFromString(@"__NSCFNumber")]) {
            str = [NSString stringWithFormat:@"@property (nonatomic, assign) int %@;",key];
        }
        if ([obj isKindOfClass:NSClassFromString(@"__NSCFArray")] || [obj isKindOfClass:NSClassFromString(@"__NSArrayI")]) {
            str = [NSString stringWithFormat:@"@property (nonatomic, copy) NSArray *%@;",key];
        }
        if ([obj isKindOfClass:NSClassFromString(@"__NSCFDictionary")]) {
            str = [NSString stringWithFormat:@"@property (nonatomic, copy) NSDictionary *%@;",key];
        }
        if ([obj isKindOfClass:NSClassFromString(@"__NSCFBoolean")]) {
            str = [NSString stringWithFormat:@"@property (nonatomic, assign) BOOL %@;",key];
        }
        
        [muStr appendFormat:@"\n%@\n",str];
    }];
    
    NSLog(@"%@",muStr);
}

添加日历时间并返回标记

+ (void)addEventNotify:(NSInteger )afterNum title:(NSString *)title AndEventBlock:(EventIndetifierBlock)eventBlock
{
    NSDateFormatter *hdateFormatter=[[NSDateFormatter alloc] init];
    [hdateFormatter setDateFormat:@"HH"];
    NSDateFormatter *mdateFormatter=[[NSDateFormatter alloc] init];
    [mdateFormatter setDateFormat:@"mm"];
    NSDateFormatter *sdateFormatter=[[NSDateFormatter alloc] init];
    [sdateFormatter setDateFormat:@"ss"];
    NSString *hs = [hdateFormatter stringFromDate:[NSDate date]];
    NSString *ms = [mdateFormatter stringFromDate:[NSDate date]];
    NSString *ss = [sdateFormatter stringFromDate:[NSDate date]];
    NSInteger fiveNum = 17 *3600;
    NSInteger endDateNum;
    if (hs.integerValue <= 17) {
        endDateNum = fiveNum - ([hs integerValue] * 60*60 + [ms integerValue]*60 + ss.integerValue);
        afterNum = afterNum + endDateNum;
    }else{
         endDateNum = ([hs integerValue] * 60*60 + [ms integerValue]*60 + ss.integerValue) - fiveNum;
         afterNum = afterNum - endDateNum;
    }
    NSDate *date = [NSDate dateWithTimeIntervalSinceNow:afterNum];
    //生成事件数据库对象
    EKEventStore *eventDB = [[EKEventStore alloc] init];
    //申请事件类型权限
    [eventDB requestAccessToEntityType:EKEntityTypeEvent completion:^(BOOL granted, NSError * _Nullable error) {
        if (granted) { //授权是否成功
            EKEvent *myEvent  = [EKEvent eventWithEventStore:eventDB]; //创建一个日历事件
            myEvent.title     = title;  //标题
            myEvent.startDate = date; //开始date   required
            myEvent.endDate   = date;  //结束date    required
            myEvent.URL = [NSURL URLWithString:@"cn.youxnet.mqqb://miqiqianbao"];
            myEvent.notes = @"cn.youxnet.mqqb://miqiqianbao";
            [myEvent addAlarm:[EKAlarm alarmWithAbsoluteDate:date]]; //添加一个闹钟  optional
            [myEvent addAlarm:[EKAlarm alarmWithRelativeOffset:60 * -1.0]];
            [myEvent setCalendar:[eventDB defaultCalendarForNewEvents]]; //添加calendar  required
            NSError *err;
            [eventDB saveEvent:myEvent span:EKSpanThisEvent error:&err]; //保存
            if (err) {
                NSLog(@"失败");
                if (eventBlock) {
                    eventBlock(@"失败");
                }
            }else{
                NSLog(@"%@",myEvent.eventIdentifier);
//                [YOLOToast showSuccessWithStatus:@"提交成功 "];
                if (eventBlock) {
                    eventBlock(myEvent.eventIdentifier);
                }
            }
        }else{
            if (eventBlock) {
                eventBlock(@"false");
            }
        }
    }];
}

UILabel滚动方式之来回滚动

+ (void)startAnimationIfNeededWith:(UILabel *)titleLabel WithFont:(NSInteger)font{
    //自定义高度
    CGSize size = [titleLabel.text sizeWithAttributes:@{NSFontAttributeName:[UIFont systemFontOfSize:font]}];
    
    if (size.width > (kScreen_Width - kFloat(100))) {
        [titleLabel setFrame:CGRectMake(0, 0, size.width, kYFloat(60))];
        float offset = size.width - kScreen_Width + kFloat(100);
        [UIView animateWithDuration:10
                              delay:0
                            options:UIViewAnimationOptionRepeat //动画重复的主开关
         |UIViewAnimationOptionAutoreverse //动画重复自动反向，需要和上面这个一起用
         |UIViewAnimationOptionCurveLinear //动画的时间曲线，滚动字幕线性比较合理
                         animations:^{
                             titleLabel.transform = CGAffineTransformMakeTranslation(offset, 0);
                         }
                         completion:^(BOOL finished) {

                         }



         ];
	}
}

UILabel滚动之循环滚动

+ (void)startAnimationIfNeededWith:(UILabel *)titleLabel WithFont:(NSInteger)font{
    //自定义高度
    CGSize size = [titleLabel.text sizeWithAttributes:@{NSFontAttributeName:[UIFont systemFontOfSize:font]}];
    
    if (size.width > (kScreen_Width - kFloat(100))) {
        [titleLabel setFrame:CGRectMake(0, 0, size.width, kYFloat(60))];
        CGRect frame = titleLabel.frame;
        frame.origin.x = 20;
        titleLabel.frame = frame;
        [UIView beginAnimations:@"testAnimation" context:NULL];
        [UIView setAnimationDuration:20];
        [UIView setAnimationCurve:UIViewAnimationCurveLinear];
        [UIView setAnimationDelegate:self];
        [UIView setAnimationRepeatAutoreverses:NO];
        [UIView setAnimationRepeatCount:9999999999];
        frame = titleLabel.frame;
        frame.origin.x = - size.width;
        titleLabel.frame = frame;
        [UIView commitAnimations];
    }
}

十六进制带透明度的颜色值

+ (UIColor *)UIColorFromHexColor:(NSString *)hexColor Andalpha:(CGFloat )alpha
{
    unsigned int red,green,blue;
    NSRange range;
    range.length = 2;
    
    range.location = 0;
    [[NSScanner scannerWithString:[hexColor substringWithRange:range]] scanHexInt:&red];
    
    range.location = 2;
    [[NSScanner scannerWithString:[hexColor substringWithRange:range]] scanHexInt:&green];
    
    range.location = 4;
    [[NSScanner scannerWithString:[hexColor substringWithRange:range]] scanHexInt:&blue];
    
    return [UIColor colorWithRed:(float)(red/255.0f) green:(float)(green / 255.0f) blue:(float)(blue / 255.0f) alpha:alpha];
}