在UIView上显示Badge（兼容IOS6）
Ios6中苹果公司吧badge 的类名改了，改成“ _UIBadgeView”了，之前是“ UITabBarButtonBadge”，在网上开到这段代码就那过来了。


- (UIView *)showBadgeValue:(NSString *)strBadgeValue  
{  
    UITabBar *tabBar = [[UITabBar alloc] initWithFrame:CGRectMake(0, 0, 320, 50)];  
    UITabBarItem *item = [[UITabBarItem alloc] initWithTitle:@"" image:nil tag:0];  
    item.badgeValue = strBadgeValue;  
    NSArray *array = [[NSArray alloc] initWithObjects:item, nil];  
    tabBar.items = array;  
    [item release];  
    [array release];  
    //寻找  
    for (UIView *viewTab in tabBar.subviews) {  
        for (UIView *subview in viewTab.subviews) {  
            NSString *strClassName = [NSString stringWithUTF8String:object_getClassName(subview)];  
            if ([strClassName isEqualToString:@"UITabBarButtonBadge"] ||  
                [strClassName isEqualToString:@"_UIBadgeView"]) {  
                //从原视图上移除  
                [subview removeFromSuperview];  
                //  
                [self addSubview:subview];  
                subview.frame = CGRectMake(self.frame.size.width-subview.frame.size.width, 0,   
                                           subview.frame.size.width, subview.frame.size.height);  
                [tabBar release];  
                return subview;  
            }  
        }  
    }  
    [tabBar release];  
    return nil;  
}  
  
- (void)removeBadgeValue  
{  
    //  
    for (UIView *subview in self.subviews) {  
        NSString *strClassName = [NSString stringWithUTF8String:object_getClassName(subview)];  
        if ([strClassName isEqualToString:@"UITabBarButtonBadge"] ||  
            [strClassName isEqualToString:@"_UIBadgeView"]) {  
            [subview removeFromSuperview];  
            break;  
        }  
    }  
}