动态显示数字

//类似于支付宝余额的动态显示
@property (nonatomic, assign) float balance;

- (void)dealloc {

    //释放定时器

    [_balanceLabelAnimationTimer invalidate];

     _balanceLabelAnimationTimer = nil;

}

- (void)setBalance:(float)balance {
    
    _balance = balance;

    [self setNumberTextOfLabel:self.moneyLab WithAnimationForValueContent:balance];
  
    
}

#pragma mark --- 余额支付的动画----
- (void)setNumberTextOfLabel:(UILabel *)label WithAnimationForValueContent:(CGFloat)value
{
    CGFloat lastValue = [label.text floatValue];
    CGFloat delta = value - lastValue;
    if (delta == 0) {
   
        label.text = @"0.00";
        return;
    }
   
    if (delta > 0) {
        
        CGFloat ratio = value / 60.0;
        
        NSDictionary *userInfo = @{@"label" : label,
                                   @"value" : @(value),
                                   @"ratio" : @(ratio)
                                   };
        _balanceLabelAnimationTimer = [NSTimer scheduledTimerWithTimeInterval:0.02 target:self selector:@selector(setupLabel:) userInfo:userInfo repeats:YES];
        [[NSRunLoop currentRunLoop] addTimer:_balanceLabelAnimationTimer forMode:NSRunLoopCommonModes];
    }
}

- (void)setupLabel:(NSTimer *)timer
{
    NSDictionary *userInfo = timer.userInfo;
    UILabel *label = userInfo[@"label"];
    CGFloat value = [userInfo[@"value"] floatValue];
    CGFloat ratio = [userInfo[@"ratio"] floatValue];
    
    static int flag = 1;
    CGFloat lastValue = [label.text floatValue];
    CGFloat randomDelta = (arc4random_uniform(2) + 1) * ratio;
    CGFloat resValue = lastValue + randomDelta;
    
    if ((resValue >= value) || (flag == 50)) {
        label.text = [NSString stringWithFormat:@"%.2f", value];
        flag = 1;
        [timer invalidate];
        timer = nil;
        return;
    } else {
        label.text = [NSString stringWithFormat:@"%.2f", resValue];
    }
    
    flag++;
    
}