Question

I have an application where I am using nsxmlparser to parse XML. But I don’t have the XML file. I have an API method which produces the XML file. I have produced the xml file in console. But the problem is I don’t know how to parse the API method. I have written the following code, but it does not produce the output.

TWeatherElement.h

//This is my element class .
#import <Foundation/Foundation.h>

@interface TWeatherElement : NSObject
{
    NSString *mIcon;
    NSString *mCurrentdate;
    NSString *mConditionname;
    NSString *mMintemp;
    NSString *mMaxtemp;
    NSString *mWind;
    NSString *mHumidity;
}

@property (nonatomic,retain) NSString *icon;
@property (nonatomic, retain)NSString *currentdate;
@property (nonatomic,retain)NSString *conditionname;
@property (nonatomic,retain)NSString *mintemp;
@property (nonatomic, retain)NSString *maxtemp;
@property (nonatomic, retain)NSString *wind;
@property (nonatomic, retain)NSString *humidity;

@end

TWeatherElement.m

#import "TWeatherElement.h"

@implementation TWeatherElement
@synthesize icon = mIcon;
@synthesize currentdate = mCurrentdate;
@synthesize conditionname = mConditionname;
@synthesize mintemp = mMintemp;
@synthesize maxtemp = mMaxtemp;
@synthesize wind = mWind;
@synthesize humidity = mHumidity;

-(void)dealloc
{
    [mIcon release];
    //[mForecastdate release];
    [mCurrentdate release];
    [mConditionname release];
    [mMintemp release];
    [mMaxtemp release];
    [mWind release];
    [mHumidity release];
    [super dealloc];
}

@end

TWeatherParser.h

//TWeatherParser is my parser class
#import "TWeatherElement.h"
#import <Foundation/Foundation.h>

@interface TWeatherParser : NSObject<NSXMLParserDelegate>
{
    NSMutableArray *mParserArray;
    NSXMLParser *mXmlParser;
    NSMutableString *mCurrentElement;
    BOOL elementFound;
    TWeatherElement *mWeather;
}
@property (nonatomic, retain) NSMutableString *currentElement;
@property (nonatomic, retain) TWeatherElement *weatherobj;

-(void)getInitialiseWithData:(NSData *)inData;

@end

TWeatherParser.m

#import "TWeatherParser.h"
#import "JourneyAppDelegate.h"
//#define kParsingFinishedNotification @"ParsingFinishedNotification"

@implementation TWeatherParser
@synthesize weatherobj = mWeatherobj;
@synthesize currentElement = mCurrentElement;

-(void)getInitialiseWithData:(NSData *)inData
{
    mWeather = [[TWeather alloc]init];
    [mParserArray removeAllObjects];
    NSBundle* bundle = [NSBundle mainBundle];

    //This is to get to the path of the xml file named contact_data, but
    //my problem is I don't have an XML file. My XML file is generated
    //through an API method, [(NSString *)getBusXMLAtStop:(NSString*)stopnumber]

    What should I write here so that I can parse my XML file which
    is retrieving through the above below API method?

}

API METHOD:
-(NSString *)getBusXMLAtStop:(NSString*)stopnumber
{
    NSError *error;
    NSURLResponse *response;
    NSData *dataReply;
    NSString *stringReply;

    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:
                                    [NSURL URLWithString: [NSString stringWithFormat:@"http://www.google.com/ig/api?weather=,,,50500000,30500000",stopnumber]]];
    [request setHTTPMethod: @"GET"];
    dataReply = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
    //NSString *str;
    stringReply = [[NSString alloc] initWithData:dataReply encoding:NSUTF8StringEncoding];
    NSLog(@"%@",stringReply);
    return stringReply;
}

-(void)parser:(NSXMLParser *)parser didStartElement:(NSString*) elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString*)qualifiedName attribute:(NSDictionary*)attributeDict
{
    if (nil!= qualifiedName)
    {
        elementName = qualifiedName;
    }
    if ([elementName isEqualToString:@"weather"])
    {
        self.weatherobj = [[TWeatherElement alloc]init];
    }
    else if([elementName isEqualToString:@"current_date_time data"]||
            [elementName isEqualToString:@"condition data"]||
            [elementName isEqualToString:@"humidity data"]||
            [elementName isEqualToString:@"icon data"]||
            [elementName isEqualToString:@"wind_condition data"]||
            [elementName isEqualToString:@"low data"]||
            [elementName isEqualToString:@"high data"])
    {
        self.currentElement = [NSMutableString string];
    }
    else
    {
        self.currentElement = nil;
    }
}

-(void)parser:(NSXMLParser*)parser foundCharacters:(NSString*)string
{
    if (nil!= self.currentElement)
    {
        [self.currentElement appendString:string];
    }
}

-(void)parser:(NSXMLParser *)parser didEndElement:(NSString*)elementName namespaceURI:(NSString*)namespaceURI qualifiedName:(NSString*)qName
{
    if (nil != qName)
    {
        elementName  = qName;
    }
    if ([elementName isEqualToString:@"current_date_time data"])
    {
        self.weatherobj.currentdate = self.currentElement;

    }
    else if ([elementName isEqualToString:@"condition data"])
    {
        self.weatherobj.conditionname = self.currentElement;

    }
    else if ([elementName isEqualToString:@"humidity data"])
    {
        self.weatherobj.humidity = self.currentElement;

    }
    else if ([elementName isEqualToString:@"icon data"])
    {
        self.weatherobj.icon = self.currentElement;

    }
    else if ([elementName isEqualToString:@"wind_condition data"])
    {
        self.weatherobj.wind = self.currentElement;

    }
    else if ([elementName isEqualToString:@"low data"])
    {
        self.weatherobj.mintemp = self.currentElement;

    }
    else if ([elementName isEqualToString:@"high data"])
    {
        self.weatherobj.maxtemp = self.currentElement;

    }

    else if ([elementName isEqualToString:@"weather"])
    {
        [mParserArray addObject:self.weatherobj];
        NSLog(@"mDataArray count = %d",[mParserArray count]);
        [self.weatherobj release];
    }
}

-(void)dealloc
{
    self.weatherobj = nil;
    self.currentElement = nil;
    [super dealloc];
}
@end

How to call the API method in the getInitialiseWithData function so that I can parse my XML file?

Answer 1

Get the string containing the XML from the API and pass the string (it must have a function that takes the string).

Or just turn the string into NSData,

NSData* data=[stringContainingXML dataUsingEncoding:NSUTF8StringEncoding];

You need to use a parser library, libxml, touchxml, or NSXMLparser. Look on Google, and do a simple tutorial. After that you should have no problem.
I suggest touchxml. I never used it, but I hear it’s easy to use compared to the rest.

Good luck mate.