Objective c NSMUTABLEARRY排序返回的顺序不正确

我试图根据两个位置（当前位置和第一个for循环中指定的坐标）之间的距离对NSMutableArray进行排序。但是，排序并没有返回任何特定的顺序，而是一个完全随机的顺序（请参见此处的图片：）

你能告诉我哪里出了问题吗

分类：

[self.venues sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {

    return [[obj1 objectForKey:@"distance"] compare:[obj2 objectForKey:@"distance"]];

}];

-设置场地：

- (void) setVenues:(NSMutableArray *)_venues {

    if (venues != _venues) {

        [venues release];

        ...

        NSMutableArray *updatedVenues = [NSMutableArray array];            

        for (NSDictionary *venue in _venues) {

            ...

            if (address != nil && city != nil) {

                CLLocationCoordinate2D coord = CLLocationCoordinate2DMake([[_location objectForKey:@"lat"] floatValue], [[_location objectForKey:@"lng"] floatValue]);

                CLLocation *currentLoc = [[CLLocation alloc] initWithLatitude:self.currentLocation.latitude longitude:self.currentLocation.longitude];
                CLLocation *venueLoc = [[CLLocation alloc] initWithLatitude:coord.latitude longitude:coord.longitude];

                CLLocationDistance distance = [venueLoc distanceFromLocation:currentLoc];

                float miles = distance / 1000;
                miles *= 0.621371192; // metres to miles

                NSMutableDictionary *newLocation = [NSMutableDictionary dictionaryWithDictionary:_location];
                [newLocation removeObjectForKey:@"distance"];
                [newLocation setObject:[NSNumber numberWithFloat:miles] forKey:@"distance"];
                _location = [NSDictionary dictionaryWithDictionary:newLocation];

                ...

                NSMutableDictionary *newVenue = [NSMutableDictionary dictionaryWithDictionary:venue];
                [newVenue removeObjectForKey:@"location"];
                [newVenue setObject:_location forKey:@"location"];                   
                [updatedVenues addObject:newVenue];

            }

        }

        venues = [updatedVenues retain];

    }

}

---

看起来您需要按地点、位置、距离进行排序：

[self.venues sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {

    NSNumber *distance1 = [[obj1 objectForKey:@"location"] objectForKey:@"distance"];
    NSNumber *distance2 = [[obj2 objectForKey:@"location"] objectForKey:@"distance"];
    return [distance1 compare:distance2];

}];

如果您使用的是Xcode>=4.4（iOS为4.5）版本，您可以执行以下操作：

[self.venues sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
    return [obj1[@"location"][@"distance"] compare:obj2[@"location"][@"distance"]];

}];

---

看起来您需要按地点、位置、距离进行排序：

[self.venues sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {

    NSNumber *distance1 = [[obj1 objectForKey:@"location"] objectForKey:@"distance"];
    NSNumber *distance2 = [[obj2 objectForKey:@"location"] objectForKey:@"distance"];
    return [distance1 compare:distance2];

}];

如果您使用的是Xcode>=4.4（iOS为4.5）版本，您可以执行以下操作：

[self.venues sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
    return [obj1[@"location"][@"distance"] compare:obj2[@"location"][@"distance"]];

}];

---

您可以将

CLLocation*currentLoc=..

移动到循环之外。在发布之前，您已经这样做了，只是没有更新代码！：）顺便说一句，您可以使用以Xcode 4.4开头的字典[@“key”]语法。您可以将

CLLocation*currentLoc=..

移动到循环之外。在发布之前是否这样做过，只是没有更新代码！：）顺便说一句，您可以使用从Xcode 4.4开始的字典[@“key”]语法。