Question

我使用以下for循环来管理/找出用户位置的五个最近注释，然后将它们设置为mapView的注释。

for (int i = 0; i <= 5; i++) {
            //NSLog(@"Stores Count For Loop: %i", [storesLessThan100KAway count]);
            if ([storesLessThan100KAway count] > 5) {
                NSSortDescriptor *descriptor = [[NSSortDescriptor alloc] initWithKey:@"distanceToTarget" ascending:YES];
                NSArray *newArray = [storesLessThan100KAway sortedArrayUsingDescriptors:[NSArray arrayWithObject:descriptor]];
                [mapView addAnnotation:[newArray objectAtIndex:i]];
                if ([[mapView annotations] count] > 4) {
                    [descriptor release];
                    [dict release];
                    [currentlocation release];
                    [usrlocation release];
                    [annotation release];
                    [paul drain];
                    [[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:NO];
                    return;
                }
            }

但是，在放大或移动地图之前，不会显示添加到地图中的注释。无论如何我可以阻止这个吗？

Answer 1

MKMapView是UIView的子类 - 您可以尝试调用[mapView setNeedsDisplay]吗？

如果不起作用：

// Force update of map view.
CLLocationCoordinate2D center = [mapView centerCoordinate];
[mapView setCenterCoordinate:center];

Answer 2

尝试将这些行放入计时器并在完成添加注释后将其停止

static float deltaX=.1;
CLLocation *location = [[[CLLocation alloc] initWithLatitude:self.mapView.centerCoordinate.latitude longitude:self.mapView.centerCoordinate.longitude] autorelease];

MKCoordinateRegion region;
region.center = location.coordinate;
MKCoordinateSpan span;

span.latitudeDelta = self.mapView.region.span.latitudeDelta+deltaX;
span.longitudeDelta = self.mapView.region.span.longitudeDelta+deltaX;
deltaX+=.1;
deltaX*=-1;
region.span = span; // Set the region's span to the new span.
[self.mapView setRegion:region animated:0];

除非放大或移动地图，否则MapView不会重新加载注释

2 个答案: