tabbar背景颜色

 //oc
    [[UITabBar appearance]setBackgroundImage:[[UIImage alloc]init]];
    
    [[UITabBar appearance]setBackgroundColor:[UIColor colorWithRed:128/255.0 green:68/255.0 blue:188/255.0 alpha:0.3]];
//    // 第二种方式
//    UIView *view = [[UIView alloc]init];
//    view.backgroundColor = [UIColor colorWithRed:128/255.0 green:68/255.0 blue:188/255.0 alpha:1];
//    view.frame = self.tabBar.bounds;
//    [[UITabBar appearance] insertSubview:view atIndex:0];