- (void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item {

    NSInteger index = [self.tabBar.items indexOfObject:item];

    if (self.indexFlag != index) {

        [self animationWithIndex:index];

    }

}

// 动画

- (void)animationWithIndex:(NSInteger) index {

    NSMutableArray * tabbarbuttonArray = [NSMutableArray array];

    for (UIView *tabBarButton in self.tabBar.subviews) {

        if ([tabBarButton isKindOfClass:NSClassFromString(@"UITabBarButton")]) {

            [tabbarbuttonArray addObject:tabBarButton];

        }

    }

    CABasicAnimation*pulse = [CABasicAnimation animationWithKeyPath:@"transform.scale"];

    pulse.timingFunction= [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];

    pulse.duration = 0.08;

    pulse.repeatCount= ;

    pulse.autoreverses= YES;

    pulse.fromValue= [NSNumber numberWithFloat:0.7];

    pulse.toValue= [NSNumber numberWithFloat:1.3];

    [[tabbarbuttonArray[index] layer]

     addAnimation:pulse forKey:nil];

    self.indexFlag = index;

}