Demo

gistfile1.m

//
//  IZGoogleGeocoder.m
//  JSON Google Geocoder
//
//  Created by Zsombor Szabó on 2/11/11.
//  Copyright 2011 IZE. All rights reserved.
//

#import "IZGoogleGeocoder.h"

#import "IZHTTPOperation.h"
#import "NSURL+Parameters.h"
#import "JSON.h"

@implementation IZGoogleGeocoder

- (id)init
{
	self = [super init];
	if (self)
	{
		operationQueue_ = [[NSOperationQueue alloc] init];
	}
	
	return self;
}

- (void)dealloc
{
	[operationQueue_ cancelAllOperations];
	[operationQueue_ release];
	[super dealloc];
}

- (void)searchForAddress:(NSString *)address // required
				location:(CLLocation *)location // required
 boundsSouthWestLocation:(CLLocation *)boundsSouthWestLocation // optional
 boundsNorthEastLocation:(CLLocation *)boundsNorthEastLocation // optional
				  region:(NSString *)region // optional
				language:(NSString *)language // optional
				  sensor:(BOOL)sensor // required
			  completion:(void (^)(id result, NSError *error))block
{
	// Sanity check
	if (address == nil && location == nil)
		return;	
	// Either address or location, and not both at the same time
	if (address && location)
		return;
	
	// Construct parameters for the URL
	NSMutableDictionary *parameters = [[NSMutableDictionary alloc] init];
	if (address)
	{
		[parameters setObject:address forKey:@"address"];
	}
	if (location)
	{
		[parameters setObject:[NSString stringWithFormat:@"%.6f,%.6f", location.coordinate.latitude, location.coordinate.longitude] 
					   forKey:@"latlng"];
	}
	if (boundsSouthWestLocation && boundsNorthEastLocation)
	{
		[parameters setObject:[NSString stringWithFormat:@"%.6f,%.6f|%.6f,%.6f", 
							   boundsSouthWestLocation.coordinate.latitude, boundsSouthWestLocation.coordinate.longitude,
							   boundsNorthEastLocation.coordinate.latitude, boundsNorthEastLocation.coordinate.longitude] 
					   forKey:@"bounds"];
	}
	if (region)
	{
		[parameters setObject:region forKey:@"region"];
	}
	if (language)
	{
		[parameters setObject:language forKey:@"language"];
	}
	if (sensor)
	{
		[parameters setObject:@"true" forKey:@"sensor"];
	}
	else
	{
		[parameters setObject:@"false" forKey:@"sensor"];
	}
	
	NSURL *requestURL = [[NSURL alloc] initWithBaseString:kGoogleAPIMapsGeocodeJSONBaseURL parameters:parameters];
	[parameters release];
	
	__block IZHTTPOperation *httpOperation = [[IZHTTPOperation alloc] initWithURL:requestURL];
	[requestURL release];
	
	// Store the current queue, so we know on which queue to call when completed
	__block NSOperationQueue *currentQueue = [NSOperationQueue currentQueue];
	
	[httpOperation setCompletionBlock:^
	{
		if ([httpOperation isCancelled])
			return;
              
		NSError *error = httpOperation.error;		
		NSData *data = httpOperation.responseBody;
		
		id json = nil;
		if (data)
		{
			NSString *jsonString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
			json = [jsonString JSONValue];
			[jsonString release];
		}

		// We finished, now let's call the block parameter on the calling queue (usually the main thread)
		[currentQueue addOperationWithBlock:^
		 {
			 block(json, error);
		 }];
	}];
	[operationQueue_ addOperation:httpOperation];
	[httpOperation release];	
}

- (BOOL)isLoading
{
	return ([operationQueue_ operationCount] > 0);
}

- (void)cancel
{
	[operationQueue_ cancelAllOperations];
}

@end