iOS中给自定义tabBar的按钮添加点击放大缩小的动画效果

// 一句话,写在UITabBarController.m脚本中,tabBar是自动执行的方法 
// 点击tabbarItem自动调用 
-(void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item 
{ 
NSInteger index = [self.tabBar.items indexOfObject:item]; 
[self animationWithIndex:index]; 
if([item.title isEqualToString:@"发现"]) 
{ 
// 也可以判断标题,然后做自己想做的事<img alt="得意" src="http://static.blog.csdn.net/xheditor/xheditor_emot/default/proud.gif" /> 
} 
} 
- (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= 1; 
pulse.autoreverses= YES; 
pulse.fromValue= [NSNumber numberWithFloat:0.7]; 
pulse.toValue= [NSNumber numberWithFloat:1.3]; 
[[tabbarbuttonArray[index] layer] 
addAnimation:pulse forKey:nil]; 
}