MKPlacemark引脚标题

Question

我的mapview工作正常，但是放在地图上的大头针的标题是美国。如何更改此标题？

    MKCoordinateRegion thisRegion = {{0.0,0.0}, {0.0,0.0}};

        thisRegion.center.latitude = 22.569722;
        thisRegion.center.longitude = 88.369722;

        CLLocationCoordinate2D coordinate;
        coordinate.latitude = 22.569722;
        coordinate.longitude = 88.369722;

        thisRegion.center = coordinate;

        MKPlacemark *mPlacemark = [[[MKPlacemark alloc] initWithCoordinate:coordinate addressDictionary:nil] autorelease];

        [mapView addAnnotation:mPlacemark];
        [mapView setRegion:thisRegion animated:YES];

Answer 1

这是一个很老的问题，但也许其他人碰巧遇到了同样的问题(和我一样)：

不要在地图的注解中添加MKPlacemark，而要使用MKPointAnnotation。此类的title和subtitle属性不是只读的。当您设置它们时，地图上的注释会相应地更新-这可能就是您想要的。

要在代码中使用MKPointAnnotation，请使用以下代码替换分配和添加MKPlacemark的行：

MKPointAnnotation *annotation = [[MKPointAnnotation alloc] init];
annotation.coordinate = coordinate;
annotation.title = NSLocalizedString(@"Dropped Pin",
                                     @"Title of a dropped pin in a map");
[mapView addAnnotation:annotation];

您也可以在以后的任何时候设置title和subtitle属性。例如，如果正在运行异步地址查询，则可以在地址可用时立即将副标题设置为注释的地址。

Answer 2

以下代码演示了在iOS 5.1中使用CLGeocoder在地图上放置注记

-(void) locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation {

CLGeocoder *geocoder = [[CLGeocoder alloc] init];

// Apple recommendation - if location is older than 30s ignore
// Comment out below during development
/*  if (fabs([newLocation.timestamp timeIntervalSinceDate:[NSDate date]]) > 30) {
    NSLog(@"timestamp");
    return;
}*/   

CLLocation *coord = [[CLLocation alloc] initWithLatitude:locationManager.location.coordinate.latitude longitude:locationManager.location.coordinate.longitude];                            
[geocoder reverseGeocodeLocation:coord completionHandler:^(NSArray *placemarks, NSError *error) {

    if (error) {
        NSLog(@"Geocode failed with error");
    }

    // check for returned placemarks
    if (placemarks && placemarks.count > 0) {
        CLPlacemark *topresult = [placemarks objectAtIndex:0];
        MKPointAnnotation *annotation = [[MKPointAnnotation alloc] init];
        annotation.coordinate = locationManager.location.coordinate;
        annotation.title = NSLocalizedString(@"You are here", @"Title");
        annotation.subtitle = [NSString stringWithFormat:@"%@, %@", [topresult subAdministrativeArea], [topresult locality]];
        [self.mapView addAnnotation:annotation];
    }
}];
}

Answer 3

查看MKPlacemark所遵循的MKAnnotation协议。您应该能够设置标题。

http://developer.apple.com/library/ios/#documentation/MapKit/Reference/MKAnnotation_Protocol/Reference/Reference.html

http://developer.apple.com/library/ios/#documentation/MapKit/Reference/MKPlacemark_Class/Reference/Reference.html