This code works some of the time, but then sometimes crashes with a EXC_BAD_ACCESS error.
NSInteger compareDistance(id num1, id num2, void *context)
{
int rv;
//cast parameters from general type
CLLocation* location = (__bridge_transfer CLLocation *)context;
Attraction* attr1 = num1;
Attraction* attr2 = num2;
//convert to CLLocation objects and calculate distance from user current
CLLocation* locationAttr1 =
[[CLLocation alloc] initWithLatitude:attr1.latitude
longitude:attr1.longitude];
CLLocation* locationAttr2 =
[[CLLocation alloc] initWithLatitude:attr2.latitude
longitude:attr2.longitude];
CLLocationDistance distance1 = [locationAttr1 distanceFromLocation:location];
CLLocationDistance distance2 = [locationAttr2 distanceFromLocation:location];
//compare and rate
if (distance1 < distance2)
rv = NSOrderedAscending;
else if (distance1 > distance2)
rv = NSOrderedDescending;
else
rv = NSOrderedSame;
return rv;
}
This is a compare function for ordering an NSMutableArray:
-(NSMutableArray *)getAttractionsByDistanceInCategory:(int)catID
{
[self confirmAttractions];
//set up array and context to prepare for sort
NSMutableArray *attractionsToSort = [[NSMutableArray alloc] init];
for (Attraction *a in attractions)
{
if ((catID < 0) || (catID >= 0 && a.category == catID))
[attractionsToSort addObject:a];
}
CLLocation* currentLocation =
[[CLLocation alloc] initWithLatitude:usersLat longitude:usersLng];
//conduct sort
[attractionsToSort sortUsingFunction:compareDistance
context:(__bridge_retained void *)currentLocation];
return attractionsToSort;
}
Hmm. Do you think the problem could be ARC? I'm side-eyeing that __bridge_retained void * business.
Thanks in advance for any advice!
__bridge_transfer transfers ownership to the destination object, which is probably not what you want to do here, you don't want ownership of the context, because ARC will try and release it when it thinks you are done with it, and you don't want it to do that.
Basically, you don't want to transfer ownership anywhere, so just use __bridge in both cases, and it should work fine.
Related
I am trying to to call MKPolylines' + polylineWithCoordinates:count: method.
How can I create a CLLocationCoordinate2D * object in this case. I have gone through this particular answer in CLLocationCoordinate2D without knowing how many will be in the array?
// unpacking an array of NSValues into memory
CLLocationCoordinate2D *points = malloc([mutablePoints count] * sizeof(CLLocationCoordinate2D));
for(int i = 0; i < [mutablePoints count]; i++) {
[[mutablePoints objectAtIndex:i] getValue:(points + i)];
}
MKPolyline *myPolyline = [MKPolyline polylineWithCoordinates:points count:[mutablePoints count]];
free(points);
What kind of entries are in the array mutablePoints in the above case?
If your question is simply what kind of entries are in the array, the answer is quite simple: NSValue entries. You can have a look at this guide for more info on how to use NSValues.
CLLocationCoordinate2D coordinate;
for (int i = 0; i < arr.count; i++)
{
float t1 = [[arr objectAtIndex:1] floatValue];
float t2 = [[arr objectAtIndex:0] floatValue];
coordinate.latitude = t1;
coordinate.longitude = t2;
}
I'm running a thread to fetch drivers location every 10 seconds and want to remove the added markers from the map but it doesn't work..
My code:
-(void)APiResponse:(id)returnJson
{
[googleMapsDriverPin setMap:nil];
googleMapsDriverPin = nil;
NSMutableArray *driverPins = [[NSMutableArray alloc]init];
for (int x = 0; x < [[returnJson valueForKey:#"drivers"] count]; x++) {
CLLocation *driverLocations = [[CLLocation alloc]initWithLatitude:[[[[returnJson valueForKey:#"drivers"] objectAtIndex:x] valueForKey:#"driver_latitude"] doubleValue] longitude:[[[[detail valueForKey:#"drivers"] objectAtIndex:x] valueForKey:#"driver_longitude"] doubleValue]];
[driverPins addObject:driverLocations];
}
for (CLLocation *newLocation in driverPins) {
googleMapsDriverPin = [[GMSMarker alloc] init];
[googleMapsDriverPin setPosition:newLocation.coordinate];
[googleMapsDriverPin setAnimated:YES];
[googleMapsDriverPin setTitle:#"title"];
[googleMapsDriverPin setSnippet:#"snippet"];
[googleMapsDriverPin setIcon:[GMSMarker markerImageWithColor:[UIColor blackColor]]];
[googleMapsDriverPin setMap:googleMaps];
}
}
It just keeps adding and adding every 10 seconds and not removing, please help!
Thanks!
Its a kind of quick and dirty option but if you wanted to go that way GMSMarker has a userData property which you could use to tag the driver pins
- (void)apiResponse:(id)returnJson
{
for (GMSMarker *pin in self.googleMaps.markers) {
if (pin.userData == #"Driver Pin"){
pin.map = nil;
}
}
...
for (CLLocation *newLocation in driverPins) {
googleMapsDriverPin = [[GMSMarker alloc] init];
...
[googleMapsDriverPin setUserData:#"Driver Pin"];
}
}
Update:
[self.googleMapsView clear];
On the based on pin id you can also delete pin.
Here deletePinId integer is for selected pin id.
for(GMSMarker *pin in self.mapView_.markers) {
NSLog(#"pin.userData : %#",pin.userData);
int pinId1 = [[pin.userData valueForKey:#"pin_id"] integerValue];
if(deltePinId == pinId1 ){
pin.map = nil;
}
}
you currently only store ONE marker, but you want to add N markers -- so (as saxon said) you need an array to hold all the pins :)
#interface YouClass
...
#property(nonatomic, retain) NSMutableArray *googleMapsDriverPins;
#end
#implementation YourClass
...
-(void)APiResponse:(id)returnJson
{
for(GMSMarker *pin in self.googleMapsDriverPins) {
pin.map = nil;
}
self.googleMapsDriverPins = nil;
NSMutableArray *driverPins = [[NSMutableArray alloc]init];
for (int x = 0; x < [[returnJson valueForKey:#"drivers"] count]; x++) {
CLLocation *driverLocations = [[CLLocation alloc]initWithLatitude:[[[[returnJson valueForKey:#"drivers"] objectAtIndex:x] valueForKey:#"driver_latitude"] doubleValue] longitude:[[[[detail valueForKey:#"drivers"] objectAtIndex:x] valueForKey:#"driver_longitude"] doubleValue]];
[driverPins addObject:driverLocations];
}
self.googleMapsDriverPins = [NSMutableArray arrayWithCapacity:driverPins.count];
for (CLLocation *newLocation in driverPins) {
GMSMarker *googleMapsDriverPin = [[GMSMarker alloc] init];
[googleMapsDriverPin setPosition:newLocation.coordinate];
[googleMapsDriverPin setAnimated:YES];
[googleMapsDriverPin setTitle:#"title"];
[googleMapsDriverPin setSnippet:#"snippet"];
[googleMapsDriverPin setIcon:[GMSMarker markerImageWithColor:[UIColor blackColor]]];
[googleMapsDriverPin setMap:googleMaps];
[self.googleMapsDriverPins addObject:googleMapsDriverPin];
}
}
#end
It looks like you have a loop adding multiple drivers, each of which assigns to the member variable googleMapsDriverPin. Then next time it removes the googleMapsDriverPin - but that will only be the last pin you added, not all of them.
For this to work you would need to add each marker inside your loop to an array, and then remove all of them from the map on your next update.
In Swift 2:
Create an outlet for your map:
#IBOutlet weak var mapView: GMSMapView!
Create an array to store all markers
var markers = [GMSMarker]()
Create markers like this:
func funcName() {
let position = CLLocationCoordinate2DMake(lat, lon)
let marker = GMSMarker(position: position)
for pin: GMSMarker in self.markers {
if pin.userData as! String == "from" {
pin.map = nil
}
}
marker.icon = UIImage(named: "navigation-red")
marker.userData = "from"
marker.map = self.mapView
self.markers.append(marker)
}
You can set the userData property to anything you want and later on use that string to delete that marker.When the funcName function is executed, all markers with userData as "from" are removed from the map.Let me know if you have any queries.
I want to sort a NSMutableArray, where each row is a NSMutableDictionary, with my GPS position from CoreLocation framework.
This is an example of my array of POI
arrayCampi = (
{
cap = 28100;
"cell_phone" = "";
championship = "IBL 1D";
citta = Novara;
division = "";
email = "";
fax = 0321457933;
indirizzo = "Via Patti, 14";
latitude = "45.437174";
league = "";
longitude = "8.596029";
name = "Comunale M. Provini";
naz = Italy;
prov = NO;
reg = Piemonte;
sport = B;
surname = "Elettra Energia Novara 2000";
telefono = 03211816389;
webaddress = "http://www.novarabaseball.it/";
})
I need to sort this array with my location (lat and long) with field 'latitude' and 'longitude' of each row in ascending mode (first row is POI nearest to me).
I have tried this solution without success:
+ (NSMutableArray *)sortBallparkList:(NSMutableArray *)arrayCampi location:(CLLocation *)myLocation {
if ([arrayCampi count] == 0) {
return arrayCampi;
}
if (myLocation.coordinate.latitude == 0.00 &&
myLocation.coordinate.longitude == 0.00) {
return arrayCampi;
}
NSMutableArray *sortedArray = [NSMutableArray arrayWithArray:arrayCampi];
BOOL finito = FALSE;
NSDictionary *riga1, *riga2;
while (!finito) {
for (int i = 0; i < [sortedArray count] - 1; i++) {
finito = TRUE;
riga1 = [sortedArray objectAtIndex: i];
riga2 = [sortedArray objectAtIndex: i+1];
CLLocationDistance distanceA = [myLocation distanceFromLocation:
[[CLLocation alloc]initWithLatitude:[[riga1 valueForKey:#"latitude"] doubleValue]
longitude:[[riga1 valueForKey:#"longitude"] doubleValue]]];
CLLocationDistance distanceB = [myLocation distanceFromLocation:
[[CLLocation alloc]initWithLatitude:[[riga2 valueForKey:#"latitude"] doubleValue]
longitude:[[riga2 valueForKey:#"longitude"] doubleValue]]];
if (distanceA > distanceB) {
[riga1 retain];
[riga2 retain];
[sortedArray replaceObjectAtIndex:i+1 withObject:riga2];
[sortedArray replaceObjectAtIndex:i withObject:riga1];
[riga1 release];
[riga2 release];
finito = FALSE;
}
}
}
return sortedArray;
}
Can anyone help me, also with other solution?
Alex.
Sorting by lat and long will not give you the nearest location from any given coordinates. As an approximation*) you could use Pythagoras (you learned that in high school, remember?):
float distance = sqrtf(powf((origLat-destLat),2)+powf((origLon-destLon), 2));
Simply add that to your dictionary with key #"distance" and sort with
NSArray *sorted = [arrayOfDictionaries sortedArrayUsingDescriptors:
#[[NSSortDescriptor sortDescriptorWithKey:#"distance" ascending:YES]]];
*) It's an approximation because theoretically distance between two points is a curved line on the surface of an ellipsoid.
[arrayCampi sortedArrayUsingSelector:#selector(compare:)];
- (NSComparisonResult)compare:(NSDictionary *)otherObject {
if ([[self objectForKey:#"key"] isEqual:[otherObject objectForKey:#"key"]]) {
return NSOrderedSame;
}
else if (//condition) {
return NSOrderedAscending;
}
else {
return NSOrderedDescending;
}
}
Take a look at How to sort an NSMutableArray with custom objects in it?
I think there's no need to implement your own sorting algorithm. There are the ready ones out there :-) I would suggest to look at NSSortDescriptor.
And since you keep your geo coordinates in NSString format, and not the NSNumber, you probably would need to write your own NSPredicate for NSString objects comparison in your class. (I don't remember if #"123" is greater than #"1.23", I mean special symbol '.')
I have been working on an iPhone app, where-in i have list of users in a NSMutableArray like below.
myMutableArray: (
{
FirstName = Getsy;
LastName = marie;
Latitude = "30.237314";
Longitude = "-92.461008";
},
{
FirstName = Angel;
LastName = openza;
Latitude = "30.260329";
Longitude = "-92.450414";
},
{
FirstName = Sara;
LastName = Hetzel;
Latitude = "30.2584499";
Longitude = "-92.4135357";
}
)
I need to sort users based on the location who is nearby to my location by calculating latitude and longitude. I am not able to achieve this till now. Could someone help me on giving some samples?
UPDATED: I am trying like below as per Mr.sch suggested. Please check my updated code. Is it fine?.
NSArray *orderedUsers = [myMutableArray sortedArrayUsingComparator:^(id a,id b) {
NSArray *userA = (NSArray *)a;
NSArray *userB = (NSArray *)b;
CGFloat aLatitude = [[userA valueForKey:#"Latitude"] floatValue];
CGFloat aLongitude = [[userA valueForKey:#"Longitude"] floatValue];
CLLocation *participantALocation = [[CLLocation alloc] initWithLatitude:aLatitude longitude:aLongitude];
CGFloat bLatitude = [[userA valueForKey:#"Latitude"] floatValue];
CGFloat bLongitude = [[userA valueForKey:#"Longitude"] floatValue];
CLLocation *participantBLocation = [[CLLocation alloc] initWithLatitude:bLatitude longitude:bLongitude];
CLLocation *myLocation = [[CLLocation alloc] initWithLatitude:locationCoordinates.latitude longitude:locationCoordinates.longitude];
CLLocationDistance distanceA = [participantALocation distanceFromLocation:myLocation];
CLLocationDistance distanceB = [participantBLocation distanceFromLocation:myLocation];
if (distanceA < distanceB) {
return NSOrderedAscending;
} else if (distanceA > distanceB) {
return NSOrderedDescending;
} else {
return NSOrderedSame;
}
}];
Thank you!
NSArray *orderedUsers = [users sortedArrayUsingComparator:^(id a,id b) {
User *userA = (User *)a;
User *userB = (User *)b;
CLLocationDistance distanceA = [userA.location getDistanceFromLocation:myLocation];
CLLocationDistance distanceB = [userB.location getDistanceFromLocation:myLocation];
if (distanceA < distanceB) {
return NSOrderedAscending
} else if (distanceA > distanceB) {
return NSOrderedDescending;
} else {
return NSOrderedSame;
}
}];
First thing, you will need to calculate the distance between your current location and the location of each other user.
Talking mathematically, here is a Wolfram|Alpha example
Now "programmatic-ally", you can use CLLocation class, here is an example:
(CLLocationDistance)getDistanceFrom:(const CLLocation *)location
But first you will need to create the location object from your Latitude and Longitude. You can use:
(id)initWithLatitude:(CLLocationDegrees)latitude longitude:(CLLocationDegrees)longitude
You can calculate the distance (geographical, not flat plane!) between your position and each of these items' positions and order by that value.
- (void)viewDidLoad {
[super viewDidLoad];
// This Array Taken Globally
List_of_locationsArray =[[NSMutableArray alloc]initWithObjects:
#{#"latitude" : #"17.415045",#"logitude":#"78.421424"} ,#{#"latitude" : #"17.415045",#"logitude":#"78.421424"},#{#"latitude" : #"17.415045",#"logitude":#"78.421424"},#{#"latitude" : #"17.415045",#"logitude":#"78.421424"},#{#"latitude" : #"17.415045",#"logitude":#"78.421424"}
,nil];
}
-(void)sortingLocationsArray{
// CLLocation* currentLocation =[[CLLocation alloc]initWithLatitude:[currentLatitude doubleValue] longitude:[currentLogitude doubleValue]];
CLLocation* currentLocation =[[CLLocation alloc]initWithLatitude: currentLatitudeHere longitude:CurrentLogHere];
NSMutableArray* tempLocationsArr = [[NSMutableArray alloc]initWithCapacity:[locationsArray count]];
for (int i=0; i<[locationsArray count]; i++) {
CLLocationDegrees latValue = [[locationsArray[i] objectForKey:#"latitude"] doubleValue];
CLLocationDegrees longValue = [[locationsArray[i] objectForKey:#"logitude"] doubleValue];
CLLocation* location = [[CLLocation alloc]initWithLatitude:latValue longitude:longValue];
[tempLocationsArr addObject:location];
NSArray* sortLocationArry = [tempLocationsArr sortedArrayUsingComparator:^NSComparisonResult(CLLocation* location1, CLLocation* location2) {
CLLocationDistance distA = [location1 distanceFromLocation:currentLocation];
CLLocationDistance distB = [location2 distanceFromLocation:currentLocation];
if (distA < distB) {
return NSOrderedAscending;
} else if ( distA > distB) {
return NSOrderedDescending;
} else {
return NSOrderedSame;
}
}];
//ArrayAfterSorting is another mutable Array to Store Sorting Data
[ArrayAfterSorting removeAllObjects];
[sortLocationArry enumerateObjectsUsingBlock:^(CLLocation* location, NSUInteger idx, BOOL *stop) {
NSMutableDictionary *tempDict = [[NSMutableDictionary alloc]init];
[tempDict setObject:[NSString stringWithFormat:#"%f",location.coordinate.latitude] forKey:#"latitude"];
[tempDict setObject:[NSString stringWithFormat:#"%f",location.coordinate.longitude] forKey:#"logitude"];
[ArrayAfterSorting addObject:tempDict];
}];
NSLog(#"sortedArray : %#", ArrayAfterSorting);
}
}
You may solve your problem in following way
1)Firstly store all above values in separate array Like latArray ,longArray,nameArray
2)Now get the distance between location(longArray,latArray) from your current location.
Then store these distances in separate Array(distanceArray).
//getDistance Between currentLocation and desired Location
-(void *)getDistanceFromCurrentLocation{
for(int val=0;val<[latArray count];val++){
NSString *dis_From_Current_Location;
dis_From_Current_Location =nil;
CGFloat str_Longitude=[[defaults objectForKey:#"long"]floatValue];
CGFloat str_Latitude=[[defaults objectForKey:#"lati"]floatValue];
//Suppose this is your current location
CGFloat lat1= [[latArray objectAtIndex:val]floatValue];
//these array for lat
CGFloat long1=[[longArray objectAtIndex:val]floatValue];
//these array for longArray
CLLocation *location1 = [[CLLocation alloc] initWithLatitude:lat1 longitude:long1];
CLLocation *location2 = [[CLLocation alloc] initWithLatitude:str_Latitude longitude:str_Longitude];
CLLocationDistance dist=[location1 distanceFromLocation:location2];
NSLog(#"Distance i meters: %f", [location1 distanceFromLocation:location2]);
long long v = llabs(dist/1000);
dis_From_Current_Location=[NSString stringWithFormat:#"%lld km",v];
[location1 release];
[location2 release];
[distanceArray addObject: dis_From_Current_Location];
//distanceArray is Global NsMutableArray.
}
}
Now You should Apply sorting method(selection, bubble) fro sorting the distances.
One thing need to care is that when you sort the distanceArray
please adjust values of nameArray as according to the distanceArray
See Below code for sorting the distanceArray and adjust the nameArray's value.
-(void)getSoretdArray{
NSString * tempStr,*tempStr2;
for(int i=0;i<[distanceArray count]; i++){
for(int j=i+1;j<[distanceArray count]; j++){
if([distanceArray objectAtIndex:j]>[distanceArray objectAtIndex:j+1]){
tempStr=[distanceArray objectAtIndex:j];
NSString* str= [distanceArray objectAtIndex:j+1];
[ distanceArray insertObject:str atIndex:j];
[distanceArray insertObject:tempStr atIndex:j+1] ;
//also change the name of corresponding location.
//you have to adjust the stored names in namArray for storing names of Corresponding Distances
tempStr2=[nameArray objectAtIndex:j];
NSString* str1= [nameArray objectAtIndex:j+1];
[ nameArray insertObject:str1 atIndex:j];
[nameArray insertObject:tempStr2 atIndex:j+1] ;
}
}
}
}
This will definitely work just try to use carefully
appdata.items is NSMutableArray.
I connot compile This code.
Error code is "prop.173 has an incomplete type".
NSInteger compareInfo(id aInfo1, id aInfo2, void *context){
NSDate* info1 = [aInfo1 objectAtIndex:2];
NSDate* info2 = [aInfo2 objectAtIndex:2];
return [info1 compare:info2];
}
-(void)saveData{
NSData* data = [[NSMutableData alloc] init];
appdata.items = [appdata.items sortUsingFunction:compareInfo context:NULL];
NSKeyedArchiver* archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:data];
[archiver encodeObject:appdata forKey:DATAKEY];
[archiver finishEncoding];
[data writeToFile:[self dataFilePath] atomically:YES];
[archiver release];
[data release];
}
Here is some code that might help you, (I spend pretty much time making it working, doc is not really helpfull)
It computes the distance between POI object and a currentLocation and order POI Object from the closest to the fartest from this location
NSInteger compareDistance(id num1, id num2, void *context)
{
int retour;
// fist we need to cast all the parameters
CLLocation* location = context;
POI* param1 = num1;
POI* param2 = num2;
// then we can use them as standard ObjC objects
CLLocation* locationCoordinates = [[CLLocation alloc] initWithLatitude:location.coordinate.latitude longitude:location.coordinate.longitude];
CLLocation* locationPOI1 = [[CLLocation alloc] initWithLatitude:param1.coords.latitude longitude:param1.coords.longitude];
CLLocation* locationPOI2 = [[CLLocation alloc] initWithLatitude:param2.coords.latitude longitude:param2.coords.longitude];
CLLocationDistance distance1 = [locationPOI1 distanceFromLocation:locationCoordinates];
CLLocationDistance distance2 = [locationPOI2 distanceFromLocation:locationCoordinates];
//make the comparaison
if (distance1 < distance2)
retour = NSOrderedAscending;
else if (distance1 > distance2)
retour = NSOrderedDescending;
else
retour = NSOrderedSame;
[locationCoordinates release];
[locationPOI1 release];
[locationPOI2 release];
return retour;
}
-(void) orderByProximityFromLocation:(CLLocationCoordinate2D) coordinates
{
CLLocation* currentLocation = [[CLLocation alloc] initWithLatitude:coordinates.latitude longitude:coordinates.longitude];
[listOfPOI sortUsingFunction:compareDistance context:currentLocation];
[currentLocation release];
}
The method sortUsingFunction:context: is for NSMutableArray, not NSArray, which sorts the contents of the mutable array. The method you want is sortedArrayUsingFunction:context: which will return a sorted array which you can assign, as you're currently trying to do.
Unless, of course, items is an NSMutableArray, in which case you can call sortUsingFunction:context: but as it doesn't return anything, so you don't assign it to items.