//过滤相同的好友请求--LQ注释
-(NSMutableArray *)arrayWithOnly:(NSMutableArray *)arr{
    NSMutableArray *array = [NSMutableArray array];
    for (ApplyEntity *model in arr) {
        [array addObject:model.receiverUsername];
    }

    NSMutableArray *categoryArr = [NSMutableArray array];
    for (int i = 0; i <array.count; i++) {
        if ([array containsObject:[array objectAtIndex:i]]==NO) {
            [categoryArr addObject:[arr objectAtIndex:i]];
        }
    }
    return categoryArr;
}