Ios UITableview中基于当前位置的排序距离

我如何根据与当前位置的距离对数组进行排序并在tableview中显示。当我使用以下代码进行排序时，我没有得到任何正确的结果，而是得到了随机距离的数组。有人能指导我解决此问题吗

-(void)sort_distance{
// Determine distance between current location and geofence location

[distance_array removeAllObjects];

NSMutableDictionary *dict=[[NSMutableDictionary alloc] init];
CLLocation *pinLocation;
CLLocation *userLocation;

for (int i=0; i<[self.geofences count]; i++) {

    //dict =[self.geofences objectAtIndex:i];

    CLLocationDegrees firstLat = [self.currentLatitude doubleValue];
    CLLocationDegrees firstLong = [self.currentLongitude doubleValue];

    CLLocationDegrees secondLat = [[[self.geofences objectAtIndex:i] objectForKey:@"lat"] doubleValue];
    CLLocationDegrees secondLong = [[[self.geofences objectAtIndex:i] objectForKey:@"lon"] doubleValue];


    pinLocation = [[CLLocation alloc]
                               initWithLatitude:secondLat
                               longitude:secondLong];

    userLocation = [[CLLocation alloc]
                                initWithLatitude:firstLat
                                longitude:firstLong];
    CLLocationDistance distance = [pinLocation distanceFromLocation:userLocation]/1000;

    //current distance is NSNumber


    CLLocationDistance kilometers = distance /1000;
    // or you can also use this..

    distanceString = [[NSString alloc] initWithFormat: @"%.1f Km", kilometers];

    NSLog(@"sa: %@", distanceString);


    [distance_array addObject:distanceString];

    [dict setObject:[NSNumber numberWithDouble:distance] forKey:@"newdistance"];


}
NSLog(@"distance array: %@", distance_array);







// Sorting the Geofence-Location depends on distance from current location


NSSortDescriptor * sort = [[NSSortDescriptor alloc] initWithKey:@"newdistance" ascending:YES];

NSArray *sortDescriptors = [NSArray arrayWithObject:sort];

sortedArray = [self.geofences sortedArrayUsingDescriptors:sortDescriptors];


}

-（void）排序距离{
//确定当前位置和土工围栏位置之间的距离
[distance_array removeAllObjects]；
NSMutableDictionary*dict=[[NSMutableDictionary alloc]init]；
CLLocation*pinLocation；
CLLocation*用户位置；
对于（int i=0；iCLLocationDistance是双精度类型，而您正在将其保存为整数类型。因此您将失去一些精度。请改用“[NSNumber numberWithDouble:”

这将按升序排序，因为降序返回的是取消排序而不是取消排序，反之亦然

-(CLLocationDistance )distanceOfCurrentPosition:(CLLocation *)userLocation WithPosition:(NSDictionary *)postition{

CLLocationDegrees secondLat = [postition[@"lat"] doubleValue];
CLLocationDegrees secondLong = [postition[@"lon"] doubleValue];

CLLocation *pinLocation = [[CLLocation alloc]
                           initWithLatitude:secondLat
                           longitude:secondLong];

CLLocationDistance distance = [pinLocation distanceFromLocation:userLocation]/1000;
CLLocationDistance kilometers = distance /1000;
return kilometers;
}

-(void)sort_distance{
CLLocationDegrees firstLat = [self.currentLatitude doubleValue];
CLLocationDegrees firstLong = [self.currentLongitude doubleValue];

CLLocation *userLocation = [[CLLocation alloc]
                            initWithLatitude:firstLat
                            longitude:firstLong];

[_geofences sortUsingComparator:^NSComparisonResult(NSDictionary *position1, NSDictionary *position2) {

    CLLocationDistance distanceWithPosition1 = [self distanceOfCurrentPosition:userLocation WithPosition:position1];
    CLLocationDistance distanceWithPosition2 = [self distanceOfCurrentPosition:userLocation WithPosition:position2];

    if (distanceWithPosition1> distanceWithPosition2) {
        return NSOrderedDescending;
    }else if(distanceWithPosition2 > distanceWithPosition1){
        return NSOrderedAscending;
    }else{
        return NSOrderedSame;
    }

}];

NSLog(@"Order :%@",_geofences);
}

-（void）排序距离{
//确定当前位置和土工围栏位置之间的距离
[distance_array removeAllObjects]；
NSMutableDictionary*dict=[[NSMutableDictionary alloc]init]；
CLLocation*pinLocation；
CLLocation*用户位置；
对于（int i=0；i请尝试这些方法对数组进行排序

-(NSArray *)sortArray:(NSArray *)arrayForSort forKey:(NSString *)key
{
    return [arrayForSort sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
        if([obj1 isKindOfClass:[NSDictionary class]] && [obj2 isKindOfClass:[NSDictionary class]])
            return [[obj1 objectForKey:key] compare:[obj2 objectForKey:key]];
        return NSOrderedSame;
    }];
}

就当是你的案子吧

self.geofenses=[self-sortArray:self.geofenses-forKey:@“newdistance”]

祝你今天愉快：）
填充时，在您的
geofences
数组中添加一个新键
currentDistance
或类似的东西，并存储该点与当前位置之间的距离如何？然后根据该键的值对数组进行排序。每次用户更改位置时，您都可以轻松更新这些值。我假设您是我们正在使用某种机制来观察位置变化。在这种情况下，使用Comparator进行SorterDarray将是一个不错的选择。尝试一下。@N00B程序员：我已尝试根据您的评论添加新键，但没有任何更改。我无法理解
距离\u数组
、
dict
和
SorterDarray
之间的关系。您是我们的哪个数组正在打印数据（在
单元格中…
）？此外，排序是在您记录阵列后完成的。记录
sortedArray
并告诉它的排序是什么。嘿@Chandu检查我的新答案。我希望能对我们有所帮助。，，，我尝试过这样做，但没有成功。请使用response type检查我的更新问题您正在self.geofenses中运行排序描述符，而您正在存储distance在一个单独的字典中。它将如何工作？它仅在一次排序距离正确时在tableview中不更新，并且始终第一个对象位于第一位。在重新加载表后，表中的位置也不会改变。AlSoSorDarray=[distance_array SortDarray UsingSelector:@selector（compare:）]；NSLog（@“%@”，SortDarray）；[\u tbl\u selectcard reloadData]；以及tableview中的哪个数组计数？？self.geofiner数组和距离标签am使用sortedArray
-(NSArray *)sortArray:(NSArray *)arrayForSort forKey:(NSString *)key
{
    return [arrayForSort sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
        if([obj1 isKindOfClass:[NSDictionary class]] && [obj2 isKindOfClass:[NSDictionary class]])
            return [[obj1 objectForKey:key] compare:[obj2 objectForKey:key]];
        return NSOrderedSame;
    }];
}