I have an iphone app which displays a list of businesses and their location on a Google Map using the MKMapView. As a new feature, I am trying to add a "Nearby" feature, whereby it gets the users current location and displays several map annotations on a google map within the vicinity of say 10KM. Currently, the businesses location is stored as an address string in a mysql database, this is then retrieved and geocoded to display it on a google map.
How do I go about doing this? If there is any tutorials around, please point me to one. (I haven't had any luck with finding one).
Thanks in advance!
UPDATE:
I got it partially working - it's only displaying businesses within a 20KM radius which is great, the problem i'm having is that when they open this Nearby Businesses View, it takes quite some time for it to go through each business and check the distance between the user and each individual business. Is there any way to speed this up? Here is my code:, both these methods are called from the viewDidLoad method.
-(void)getMapData
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc]init];
NSInteger *bizMax = [[numOfBiz objectAtIndex:0]intValue];
int x = 0;
while(x < bizMax)
{
NSURL *mapURL = [NSURL URLWithString:[NSString stringWithFormat:#"getBizMap-xml.php?biz_id=%#",[bizIDS objectAtIndex:x]]];
NSMutableArray *mapArray = [[NSMutableArray alloc] initWithContentsOfURL:mapURL];
self.mapLocation = mapArray;
self.mapStringLocation = [mapArray objectAtIndex:0];
NSLog(#"Location: %#",mapStringLocation);
[mapArray release];
CLLocationCoordinate2D trueLocation = [self getLocationFromAddressString:mapStringLocation];
AddressAnnotation *addAnnotation = [[AddressAnnotation alloc] initWithCoordinate:trueLocation];
CLLocation *bizLoc = [[CLLocation alloc] initWithLatitude:trueLocation.latitude longitude:trueLocation.longitude];
CLLocation *userLocation = [[CLLocation alloc] initWithLatitude:nearbyMapView.userLocation.coordinate.latitude longitude:nearbyMapView.userLocation.coordinate.longitude];
//double distance = [userLocation getDistanceFrom: bizLoc] / 1000;
double kilometers = [userLocation distanceFromLocation:bizLoc] / 1000;
NSLog(#"Distance from %# to current location is %g",mapStringLocation,kilometers);
if(kilometers < maxDistance)
{
[self.nearbyMapView addAnnotation:addAnnotation];
[addAnnotation release];
}
x++;
}
[pool release];
}
-(void)getNumOfBusinesses
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc]init];
NSString *numOfBizJSON = [[NSString alloc]initWithContentsOfURL:[NSURL URLWithString:[NSString stringWithFormat:#"numOfBiz.php"]]];
NSString *bizIDSJSON = [[NSString alloc]initWithContentsOfURL:[NSURL URLWithString:[NSString stringWithFormat:#"allBizIDSJSON.php"]]];
SBJsonParser *parser = [[SBJsonParser alloc]init];
numOfBiz = [[parser objectWithString:numOfBizJSON error:nil]copy];
bizIDS = [[parser objectWithString:bizIDSJSON error:nil]copy];
NSLog(#"biz id 1 = %#",[bizIDS objectAtIndex:0]);
[parser release];
[numOfBizJSON release];
[bizIDSJSON release];
[pool release];
}
This isn't that hard. You can fetch all your data, calculate the distance between you and the location. The next step would be comparing the distance with the maxDistance(the search radius). If the distance < maxDistance, add you can display that location.
I think this could be achieved with very little cocoa knowledge...
If you need something more specific, start coding and I'll help you with that.
Related
My app is real-time tracker, where multiple users are logged in and updating their location by sending their co-ordinates to our web service which is then called back let's after every 2 minutes to show all the users on my MapView.
Every time I get the locations of users from web service in connectionDidFinishLoading method, I am parsing, creating polyline through pointsArray and adding them to overlay:
-(void) connectionDidFinishLoading: (NSURLConnection *) connection
{
userLatitudeArray = [[NSMutableArray alloc]init];
userLongitudeArray = [[NSMutableArray alloc]init];
userIdArray = [[NSMutableArray alloc]init];
userNameArray = [[NSMutableArray alloc]init];
userProfilePicArray = [[NSMutableArray alloc]init];
profilePicURLStringArray = [[NSMutableArray alloc]init];
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
NSArray *trackingDict = [NSJSONSerialization JSONObjectWithData:empJsonData options:kNilOptions error:nil];
if ([trackingDict count] >= 2) {
for (trackUsersCount = 0; trackUsersCount< trackingDict.count; trackUsersCount++) {
NSLog(#"trackUsersCount %i", trackUsersCount);
NSMutableArray *latlongArray = [[NSMutableArray alloc]init];
latlongArray = [[trackingDict objectAtIndex:trackUsersCount]objectForKey:#"latlong"];
[userLongitudeArray removeAllObjects];
[userLatitudeArray removeAllObjects];
for (int i = 0; i<latlongArray.count; i++) {
[userLatitudeArray addObject:[[latlongArray objectAtIndex:i]objectForKey:#"lat"]];
[userLongitudeArray addObject:[[latlongArray objectAtIndex:i]objectForKey:#"long"]];
}
NSString *name = [[trackingDict objectAtIndex:trackUsersCount]objectForKey:#"user_firstName"];
// ProfilePIC URL
profilePicURLString = [[trackingDict objectAtIndex:trackUsersCount]objectForKey:#"user_profilePicture"];
[userNameArray addObject:name];
[profilePicURLStringArray addObject:profilePicURLString];
int i;
if (userLatitudeArray.count>1) {
for (i = 0; i<userLatitudeArray.count; i++) {
CLLocationCoordinate2D userLocation;
userLocation.latitude = [[userLatitudeArray objectAtIndex:i]doubleValue];
userLocation.longitude = [[userLongitudeArray objectAtIndex:i] doubleValue];
MKMapPoint * pointsArray = malloc(sizeof(CLLocationCoordinate2D)*userLongitudeArray.count);
pointsArray[i] = MKMapPointForCoordinate(userLocation);
polyline = [MKPolyline polylineWithPoints:pointsArray count:i];
free(pointsArray);
}
polyline.title = name;
[mapView addOverlay:polyline];
}
}
}
}
What I want to do is to have control on each polyline created for each user, so I can change the color of it and hide/show them on click of a button (one to show/hide my track and the other for all other users), this is why I am adding title to it.
I can see now that I am adding polyline to the same overlay, which is wrong I believe. But I don't know how many users will be there in web-service so can add multiple overlays of them.
Initially I thought I am able to remove a particular polyline with title but then I realised it is removing all as polyline.title property gets updated.
Any help would be much appreciated!
You could collect an array of those tracks that relate to other users, and keep a single track for the current user. If you clean the array at the start of the connectionDidFinishLoading function and populate it where you are currently adding the overlays to the map, then you move the addOverlay to a new function that you call at the end.
- (void) resetMap
{
if (showOtherTracks)
{
[mapView addOverlays:otherUserTracks];
} else {
[mapView removeOverlays:otherUserTracks];
}
if (showMyTrack)
{
[mapView addOverlay:myTrack];
} else {
[mapView removeOverlay:myTrack];
}
}
You can also call this when ever the button is pressed and the state changes.
I am trying to add some annotations to my mkMapView in this loop:
for (PFObject *fetchedCompany in companyArray)
{
Store *store = [[Store alloc] initWithObject:fetchedCompany];
[self loadStore:store];
[store release];
}
- (void) loadStore:(Store *) store {
CLLocationCoordinate2D location = [self getLocationFromAddressString:store.address];
MapViewAnnotation *mapAnnotation = [[MapViewAnnotation alloc] initWithTitle:store.name coordinate:location];
[self.indexMapView addAnnotation:mapAnnotation];
}
And this the getLocationFromAddressString method that convert the address to a location using google api:
-(CLLocationCoordinate2D) getLocationFromAddressString:(NSString*) addressStr {
NSString *urlStr = [NSString stringWithFormat:#"http://maps.google.com/maps/geo?q=%#&output=csv", [addressStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
NSError *error = nil;
NSString *locationStr = [NSString stringWithContentsOfURL:[NSURL URLWithString:urlStr] encoding:NSUTF8StringEncoding error:&error];
NSArray *items = [locationStr componentsSeparatedByString:#","];
double lat = 0.0;
double lon = 0.0;
if([items count] >= 4 && [[items objectAtIndex:0] isEqualToString:#"200"]) {
lat = [[items objectAtIndex:2] doubleValue];
lon = [[items objectAtIndex:3] doubleValue];
}
else {
NSLog(#"Address, %# not found: Error %#",addressStr, [items objectAtIndex:0]);
}
CLLocationCoordinate2D location;
location.latitude = lat;
location.longitude = lon;
return location;
}
When I send just one location always it works perfectly, but when I add annotations in my loop sometimes some locations could not be recognized and I got the error from my NSLog:
Address, Vallgatan 3 GÖTEBORG not found: Error 620
The thing is I am pretty sure about the addresses because when I tried them without loop they worked. Do you know how can I solve the problem?
You've submitted too many queries and your request got rejected. See Geocoding API V2 docs.
620: G_GEO_TOO_MANY_QUERIES
"The given key has gone over the requests limit in the 24 hour period or has submitted too many requests in too short a period of time. If you're sending multiple requests in parallel or in a tight loop, use a timer or pause in your code to make sure you don't send the requests too quickly"
I want to add a number of annotations(arround 500) on a mapview but the maximum it seems to display is 100. If I go beyond 100, viewForAnnotation delegate method is not called. However it works perfectly for annotations below 100.
here is the code: (works only when count of annotationArray array is less than 101)
_allPoints = [[NSMutableArray alloc] init];
NSString* responseFile = [[NSBundle mainBundle] pathForResource:#"Datafile" ofType:#"txt"];
NSData *sampleData = [NSData dataWithContentsOfFile:responseFile];
if (sampleData) {
NSError* error;
NSDictionary* json = [NSJSONSerialization
JSONObjectWithData:sampleData
options:kNilOptions
error:&error];
NSArray* response = [json objectForKey:#"response"];
for (NSDictionary *lineDict in response) {
if ([[lineDict objectForKey:#"data"] isKindOfClass:[NSArray class]]) {
SinglePoint *singlePoint = [[SinglePoint alloc] initWithDictionary:lineDict];
[_allPoints addObject:singlePoint];
}
else {
NSLog(#"Error");
}
}
}
_mapView = [[MKMapView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
[_mapView setDelegate:self];
[self.view addSubview:_mapView];
NSMutableArray *annotationArray = [[NSMutableArray alloc] init];
for (int i=0; i<[_allPoints count]; i++) {
SinglePoint *singlePoint = [_allPoints objectAtIndex:i];
NVPolylineAnnotation *annotation = [[NVPolylineAnnotation alloc] initWithPoint:singlePoint mapView:_mapView];
[annotationArray addObject:annotation];
}
[_mapView addAnnotations:(NSArray *)annotationArray];
CLLocationCoordinate2D centerCoord = { 28.632747, 77.219982 };
[_mapView setCenterCoordinate:centerCoord zoomLevel:12 animated:NO];
The delegate method is:
EDIT: As per comments, started reusing the view but with no luck :(
if ([annotation isKindOfClass:[NVPolylineAnnotation class]]) {
static NSString *viewIdentifier = #"annotationView";
NVPolylineAnnotationView *annotationView = (NVPolylineAnnotationView *) [mapView dequeueReusableAnnotationViewWithIdentifier:viewIdentifier];
if (annotationView == nil) {
annotationView = [[NVPolylineAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:viewIdentifier mapView:_mapView];
}
return annotationView;
}
return nil;
I could not find any restriction in the documentation or anywhere else. Could it be memory issue?
The MKMapView has not Limit for annotationViews. But it gets quite laggy and unusable above a certain number of views (+1000).
I believe, that the reason for this is that you handle the annotationView management totally wrong. You shouldn't create a unique view for every single annotation, even if you are using ARC. Your rather should reuse every unused View like the cell of a UITableView.
There are a couple of good tutorials for this like Introduction to MapKit on iOS - Ray Wenderlich.
If this won't resolve your problem, you should try to debug your annotation classes. (NVPolylineAnnotation and NVPolylineAnnotationView). Maybe there's something wrong.
Did you also checked your points array for equal coordinates?
Finally was able to track down the problem. Solved it by setting the center of mapView first and then adding annotations later. I still dont know why 100 annotations were shown earlier (and why the no 100 only). Thank you all for your suggestions and time on this.
This is the code I changed:-
_mapView = [[MKMapView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
[_mapView setDelegate:self];
[self.view addSubview:_mapView];
CLLocationCoordinate2D centerCoord = { 28.632747, 77.219982 };
[_mapView setCenterCoordinate:centerCoord zoomLevel:12 animated:NO];
NSMutableArray *annotationArray = [[NSMutableArray alloc] init];
for (int i=0; i<[_allPoints count]; i++) {
SinglePoint *singlePoint = [_allPoints objectAtIndex:i];
NVPolylineAnnotation *annotation = [[NVPolylineAnnotation alloc] initWithPoint:singlePoint mapView:_mapView];
[annotationArray addObject:annotation];
}
[_mapView addAnnotations:(NSArray *)annotationArray];
You can add as many annotations as you like. However, the views for each annotation will not be created until that annotation's coordinate property intersects with the visible portion of your map view. MapKit will not create a view just because you added an annotation to the map.
I have a MKMapView, and I would like to know how I can find the nearest 5 annotations to the user, and only display them on the MKMapView.
My code currently is:
- (void)loadFiveAnnotations {
NSString *string = [[NSString alloc] initWithContentsOfURL:url];
string = [string stringByReplacingOccurrencesOfString:#"\n" withString:#""];
NSArray *chunks = [string componentsSeparatedByString:#";"];
NSArray *keys = [NSArray arrayWithObjects:#"type", #"name", #"street", #"address1", #"address2", #"town", #"county", #"postcode", #"number", #"coffeeclub", #"latlong", nil];
// max should be a multiple of 12 (number of elements in keys array)
NSUInteger max = [chunks count] - ([chunks count] % [keys count]);
NSUInteger i = 0;
while (i < max)
{
NSArray *subarray = [chunks subarrayWithRange:NSMakeRange(i, [keys count])];
NSDictionary *dict = [[NSDictionary alloc] initWithObjects:subarray forKeys:keys];
// do something with dict
NSArray *latlong = [[dict objectForKey:#"latlong"] componentsSeparatedByString:#","];
NSString *latitude = [[latlong objectAtIndex:0] stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
NSString *longitude = [[latlong objectAtIndex:1] stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
CLLocationDegrees lat = [latitude floatValue];
CLLocationDegrees longi = [longitude floatValue];
Annotation *annotation = [[Annotation alloc] initWithCoordinate:CLLocationCoordinate2DMake(lat, longi)];
annotation.title = [dict objectForKey:#"name"];
annotation.subtitle = [NSString stringWithFormat:#"%#, %#, %#",[dict objectForKey:#"street"],[dict objectForKey:#"county"], [dict objectForKey:#"postcode"]];
[mapView addAnnotation:annotation];
[dict release];
i += [keys count];
}
}
A long answer, already mostly written when Stephen Poletto posted and containing example code on how to use the built-in methods for sorting an array, so I though it was still worth posting though the essential answer is the same (ie, "pick the five closest for yourself, pass only those on"):
You're going to need to sort your annotations by distance for yourself, and submit only the closest five to the MKMapView. If you have two CLLocations then you can get the distance between them using the distanceFromLocation: method (which was getDistanceFrom: prior to iOS 3.2; that name is now deprecated).
So, for example, supposing your Annotation class had a method 'setReferenceLocation:' to which you pass a CLLocation and a getter 'distanceFromReferenceLocation' which returns the distance between the two, you could do:
// create and populate an array containing all potential annotations
NSMutableArray *allPotentialAnnotations = [NSMutableArray array];
for(all potential annotations)
{
Annotation *annotation = [[Annotation alloc]
initWithCoordinate:...whatever...];
[allPotentialAnnotations addObject:annotation];
[annotation release];
}
// set the user's current location as the reference location
[allPotentialAnnotations
makeObjectsPerformSelector:#selector(setReferenceLocation:)
withObject:mapView.userLocation.location];
// sort the array based on distance from the reference location, by
// utilising the getter for 'distanceFromReferenceLocation' defined
// on each annotation (note that the factory method on NSSortDescriptor
// was introduced in iOS 4.0; use an explicit alloc, init, autorelease
// if you're aiming earlier)
NSSortDescriptor *sortDescriptor =
[NSSortDescriptor
sortDescriptorWithKey:#"distanceFromReferenceLocation"
ascending:YES];
[allPotentialAnnotations sortUsingDescriptors:
[NSArray arrayWithObject:sortDescriptor]];
// remove extra annotations if there are more than five
if([allPotentialAnnotations count] > 5)
{
[allPotentialAnnotations
removeObjectsInRange:NSMakeRange(5,
[allPotentialAnnotations count] - 5)];
}
// and, finally, pass on to the MKMapView
[mapView addAnnotations:allPotentialAnnotations];
Depending on where you're loading from, you made need to create a local store (in memory or on disk) for annotations and select the five nearest whenever the user moves. Either register yourself as a CLLocationManager delegate or key-value observe on the map view's userLocation property. If you have quite a lot of potential annotations then sorting all of them is a bit wasteful and you'd be better advised to use a quadtree or a kd-tree.
First you'll need to grab the user's current location. You can build a CLLocationManager and register yourself as the delegate for location updates as follows:
locationManager = [[[CLLocationManager alloc] init] autorelease];
[locationManager setDelegate:self];
[locationManager startUpdatingLocation];
After setting yourself as the delegate, you'll receive the following callback:
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
Now that you have the user's location (newLocation), you can find the five closest annotations. There is a handy method in CoreLocation:
- (CLLocationDistance)distanceFromLocation:(const CLLocation *)location
As you're iterating through your annotations, just store the five nearest locations. You can build a CLLocation out of the 'lat' and 'longi' variables you have using:
- (id)initWithLatitude:(CLLocationDegrees)latitude longitude:(CLLocationDegrees)longitude
Hope this helps!
i want to show multiple pins on my MapView all with Animation of Dropping pin so how it is possible if any body have sample code then please send send link.i am new in this field.Thanks in Advance.
There are few code samples on developer.apple.com
This
is a simple map example with two pins
Just as you show single pin.. keep the code for single pin in Loop and pass different longitude latitude in loop.. You will get the pins at different location
if([points retainCount] > 0)
{
[points release];
points = nil;
}
if([annotationAry retainCount] > 0)
{
[annotationAry release];
annotationAry = nil;
}
points = [[NSMutableArray alloc]init];
annotationAry = [[NSMutableArray alloc]init];
for(int i=0;i<[longitudeary count];i++)
{
CLLocation* currentLocation1 = [[CLLocation alloc] initWithLatitude:[[latitudeary objectAtIndex:i]doubleValue] longitude:[[longitudeary objectAtIndex:i]doubleValue]];
[points addObject:currentLocation1];
}
for(int i=0;i<[points count];i++)
{
// CREATE THE ANNOTATIONS AND ADD THEM TO THE MAP
CSMapAnnotation* annotation = nil;
// create the start annotation and add it to the array
annotation = [[[CSMapAnnotation alloc] initWithCoordinate:[[points objectAtIndex:i] coordinate]
annotationType:CSMapAnnotationTypeImage
title:#"123456..."
shID:[shIDary objectAtIndex:i]
catID:[catIDary objectAtIndex:i]
ciggUse:[ciggaretteUSEary objectAtIndex:i]
wifiUse:[wifiUSEary objectAtIndex:i]
controller:self]autorelease];
[annotationAry addObject:annotation];
}
[mapViewmy addAnnotations:[NSArray arrayWithArray:annotationAry]];