iOS常用扩展类,宏

NSObject扩展类

/**
 *  从XIB文件中初始化ViewController,类名与XIB文件名一致
 *
 *  @return VC
 */
+ (id)viewControllerFromNIB {
    if (![self class]) return nil;
    return [[[self class] alloc] initWithNibName:NSStringFromClass([self class]) bundle:nil];
}