mapview不显示注释点

Question

我想绘制mapview中的一个点。 我创建了两个文件 1.一个扩展了nsobject的文件，以及一个扩展视图的文件。 下面是这两个文件的源代码：

#import "gpMapViewAnnotations.h" 

@implementation gpMapViewAnnotations 
@synthesize title, coordinate; 

- (id)initWithTitle:(NSString *)ttl andCoordinate:(CLLocationCoordinate2D)c2d { 

    title = ttl; 
    coordinate = c2d; 
    return self; 
} 

这是接口文件的代码。

#import <Foundation/Foundation.h> 
#import <MapKit/MapKit.h> 

@interface gpMapViewAnnotations : NSObject <MKAnnotation>{ 

    NSString *title; 
    CLLocationCoordinate2D coordinate; 
} 
@property (nonatomic, copy) NSString *title; 
@property (nonatomic, readonly) CLLocationCoordinate2D coordinate; 

- (id)initWithTitle:(NSString *)ttl andCoordinate:(CLLocationCoordinate2D)c2d; 


@end 

@end

现在，这是视图文件的源代码：

#import <UIKit/UIKit.h> 
#import <MapKit/Mapkit.h> 
#import "ASIHTTPRequestDelegate.h" 
#import "AppDelegate.h" 
#import "gpMapViewAnnotations.h" 

@interface gpViewController : UIViewController 
< ASIHTTPRequestDelegate, MKMapViewDelegate> 
{ 
    MKMapView *gpMapView; 


    gpMapViewAnnotations *gpAnnotations; 

} 
@property (strong, nonatomic) IBOutlet MKMapView *gpMapView; 

@end 

，这里是实现文件：

#import "gpViewController.h" 
#import "ASIHTTPRequest.h" 
#import "Parser.h" 
#import "AppDelegate.h" 
#import "TFHpple.h" 
#import "TouchXML.h" 
#import "gpMapViewAnnotations.h" 


@interface gpViewController() 

@end 

@implementation gpViewController 
@synthesize gpMapView; 


- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil 
{ 
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; 
    if (self) { 

    } 
    return self; 
} 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 
    // Do any additional setup after loading the view from its nib. 
    // Set some coordinates for our position (Buckingham Palace!) 
    CLLocationCoordinate2D location; 
    location.latitude = (double) 51.501468; 
    location.longitude = (double) -0.141596; 

    // Add the annotation to our map view 
    gpMapViewAnnotations *newAnnotation = [[gpMapViewAnnotations alloc] initWithTitle:@"Buckingham Palace" andCoordinate:location]; 
    [gpMapView addAnnotation:newAnnotation]; 

    NSURL *url = [NSURL URLWithString:@"http://v1.syndication.nhschoices.nhs.uk/organisations/gppractices/location.xml?apikey=YAHUGHET&range=50&northing=174900&easting=517900&name=richmond"]; 
    ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url]; 

    [request setDelegate:self]; 

    [request startAsynchronous]; 
    [gpMapView setDelegate:self]; 

} 

- (void)viewDidUnload 
{ 
    [self setGpMapView:nil]; 
    [super viewDidUnload]; 
    // Release any retained subviews of the main view. 
    // e.g. self.myOutlet = nil; 
} 

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation 
{ 
    return YES; 
} 

- (void)requestFinished:(ASIHTTPRequest *)request 
{ 
    NSLog(@"view did load"); 
    NSLog(@"request finished"); 
    // Use when fetching text data 
    NSString *responseString = [request responseString]; 
// NSLog(@"%@",responseString); 
    // Use when fetching binary data 

    NSData *responseData = [request responseData]; 

    // we will put parsed data in an a array 
    NSMutableArray *res = [[NSMutableArray alloc] init]; 
    // using local resource file 
    // NSString *XMLPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"test.xml"]; 
    // NSData *XMLData = [NSData dataWithContentsOfFile:responseString]; 
    CXMLDocument *doc = [[CXMLDocument alloc] initWithData:responseData options:0 error:nil]; 

    NSArray *nodes = NULL; 
    // searching for piglet nodes 
    nodes = [doc nodesForXPath:@"//*" error:nil]; 
    NSLog(@"coming here 1"); 
    for (CXMLElement *node in nodes) { 
     //NSLog(@"coming here 2"); 

     // NSMutableArray *item = [[NSMutableArray alloc]init]; 
     //create list object to store the title and latitude and longitude. 
     List *gpList = [[List alloc]init]; 

     if([[node localName] isEqualToString:@"entry"]){ 
      NSArray *entryTagNodes = [node children]; 

      //iterate on entry nodes 
      for(CXMLElement *entryTagNode in entryTagNodes){ 
       //check if the tagname is content 
       if([[entryTagNode localName] isEqualToString:@"content"]){ 
         //iterat on content tag childs 
        NSArray *contentTagNodes = [entryTagNode children]; 
        // NSLog(@"tag: %d",[contentTagNodes count]); 
        for(CXMLElement *innerContentNode in contentTagNodes){ 

         NSArray *organisationTagNodes = [innerContentNode children]; 
         for(CXMLElement *orgTagNode in organisationTagNodes){ 
          // NSLog(@"%@",[orgTagNode localName]); 

           //check for tag name is equal to name 
          if([[orgTagNode localName] isEqualToString:@"name"]){ 
           gpList.title = [orgTagNode stringValue]; 

          }else if([[orgTagNode localName] isEqualToString:@"geographicCoordinates"]){ 
           NSArray *geoCordTags = [orgTagNode children]; 

           for(CXMLElement *geoCordTag in geoCordTags){ 
            if([[geoCordTag localName] isEqualToString:@"latitude"]){ 
             gpList.latitude = [geoCordTag stringValue]; 

            }else if([[geoCordTag localName] isEqualToString:@"longitude"]){ 
             gpList.longitude = [geoCordTag stringValue]; 
            } 

           } 
           NSLog(@"latitude nad longitude %@ %@",gpList.latitude,gpList.longitude); 

          } 
         } 
        } 


       } 

      } 
      [res addObject:gpList]; 

     } 

     // and here it is - attributeForName! Simple as that. 
     // [item setObject:[[node valueForKey:@"id"] stringValue] forKey:@"id"]; // <------ this magical arrow is pointing to the area of interest 



    } 

    // and we print our results 
    // NSLog(@"%@", res); 
    NSEnumerator *enumerator = [res objectEnumerator]; 
    id obj; 
    while(obj = [enumerator nextObject]){ 

      NSLog(@"title %@",[obj title]); 

    } 

    /* 
    TFHpple *doc = [TFHpple hppleWithData:responseData isXML:YES]; 
    NSArray *elements = [doc searchWithXPathQuery:@"/"]; 

    NSLog(@"%d",[elements objectAtIndex:0]); 
    */ 
    /* 
    NSXMLParser *xmlParser = [[NSXMLParser alloc] initWithData:responseData]; 
    Parser *parser = [[Parser alloc] initParser]; 

    [xmlParser setDelegate:parser]; 
    BOOL worked = [xmlParser parse]; 
    if(worked){ 
     NSLog(@"parsing is happening "); 

    }else{ 
     NSLog(@"parsing is not happening %@",[app.listArray count]); 
    }*/ 


} 

-(void)mapView:(MKMapView *)mv didAddAnnotationViews:(NSArray *)views{ 
    MKAnnotationView *annotationView = [views objectAtIndex:0]; 
    id <MKAnnotation> mp = [annotationView annotation]; 
    MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance([mp coordinate], 1500, 1500); 
    [mv setRegion:region animated:YES]; 
    [mv selectAnnotation:mp animated:YES]; 
} 

- (void)requestFailed:(ASIHTTPRequest *)request 
{ 
    NSError *error = [request error]; 
    NSLog(@"%@",error); 
} 

@end 

我没有一个线索我在绘制一个简单的点时做错了。我仍然需要使用我创建的读取XML文件的数组放置多个点。但即使是一个简单的观点现在也没有被绘制出来。 请问我在这里做错了什么？

Answer 1

我看不到你的mapView:viewForAnnotation:委托方法。这就是您可以添加视图以跟踪注释的地方。像这样的东西：

- (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation 
{ 
    if(annotation == mapView.userLocation) return nil; 

    MKPinAnnotationView *annotationView; 
    annotationView = (MKPinAnnotationView*)[mapView dequeueReusableAnnotationViewWithIdentifier:@"AnnotationIdentifier"]; 
    if(annotationView == nil){ 
     annotationView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"AnnotationIdentifier"]; 
    } 

    return annotationView; 
}