iOS支付宝金额跳动的效果

#import "UILabel+JumpNumber.h"#import <objc/runtime.h>#define kRangeNumberKey @"RangeKey"         //每次数字跳动相差的间隔数#define kBeginNumberKey @"BeginNumberKey"   //起始数字#define kEndNumberKey @"EndNumberKey"       //结束跳动时的数字#define kFormatKey @"FormatStringKey"       //字符串格式#define kFrequency 1.0/30.0f                //数字跳动频率#define kRangeNumber(endNumber,duration) (endNumber * kFrequency)/duration@interface UILabel ()@property (nonatomic, strong) NSNumber *flickerNumber;@property (nonatomic, strong) NSTimer *currentTimer;@end@implementation UILabel (JumpNumber)#pragma mark - getter & setter methods//No.1//开始写代码，完成 "flickerNumber" 和 "currentTimer" 的getter、setter方法- (void)setFlickerNumber:(NSNumber *)flickerNumber {    objc_setAssociatedObject(self, "flickerNumber", flickerNumber, OBJC_ASSOCIATION_RETAIN_NONATOMIC);}- (NSNumber *)flickerNumber {    return objc_getAssociatedObject(self, "flickerNumber");}- (void)setCurrentTimer:(NSTimer *)currentTimer {    objc_setAssociatedObject(self, "currentTimer", currentTimer, OBJC_ASSOCIATION_RETAIN_NONATOMIC);}- (NSTimer *)currentTimer {    return objc_getAssociatedObject(self, "currentTimer");}//end_code#pragma mark - flicker methods(public)- (void)oxc_setNumber:(NSNumber *)number {    [self oxc_setNumber:number duration:1.0 format:nil];}- (void)oxc_setNumber:(NSNumber *)number format:(NSString *)formatStr {    [self oxc_setNumber:number duration:1.0 format:formatStr];}- (void)oxc_setNumber:(NSNumber *)number duration:(NSTimeInterval)duration format:(NSString *)formatStr{    /*检查是否是数字类型*/    if(![number isKindOfClass:[NSNumber class]]){        self.text = [NSString stringWithFormat:@"%@",number];        return;    }    [self.currentTimer invalidate];    self.currentTimer = nil;    /*变量初始化*/    self.flickerNumber = @(0);    int beginNumber = 0;    int endNumber = [number intValue];    NSMutableDictionary *userInfo = [NSMutableDictionary dictionaryWithCapacity:0];    if(formatStr) {        [userInfo setObject:formatStr forKey:kFormatKey];    }    [userInfo setObject:@(beginNumber) forKey:kBeginNumberKey];    [userInfo setObject:number forKey:kEndNumberKey];    [userInfo setObject:@(kRangeNumber(endNumber, duration)) forKey:kRangeNumberKey];    self.currentTimer = [NSTimer scheduledTimerWithTimeInterval:kFrequency target:self selector:@selector(flickerAnimation:) userInfo:userInfo repeats:YES];    [[NSRunLoop currentRunLoop] addTimer:self.currentTimer forMode:NSRunLoopCommonModes];}#pragma mark - private methods- (void)flickerAnimation:(NSTimer *)timer{    //No.2    //开始写代码，根据前后代码补全每次数字跳动的实现过程    //获取字典信息    NSMutableDictionary *info = timer.userInfo;    int begin = (int)[info objectForKey:kBeginNumberKey];    int end = ((NSNumber *)[info objectForKey:kEndNumberKey]).intValue;    int range = ((NSNumber *)[info objectForKey:kRangeNumberKey]).intValue;//    NSString *format = [info objectForKey:kFormatKey];    //获取text值 如果为0表示第一次；如果大于end表示到达最大值，结束定时器；否则显示当前数加上间隔数    int value = self.text.intValue;//    NSLog(@"%d, %d, %d, %d", value, begin, end, range);    if (value == 0) {        self.text = [NSString stringWithFormat:@"%d", begin];    }    else if (value >= end) {        self.text = [NSString stringWithFormat:@"%d", end];        [self.currentTimer invalidate];        self.currentTimer = nil;        return;    }    else {        value += range;        self.text = [NSString stringWithFormat:@"%d", value];    }    //end_code}- (NSString *)finalString:(NSNumber *)number stringFormat:(NSString *)formatStr {    NSAssert([formatStr rangeOfString:@"%@"].location != NSNotFound, @"string format type is not matched,please check your format type");    return [NSString stringWithFormat:formatStr,number];}@end