我正在尝试将地图的缩放级别设置为仅包含注释,但也不要缩放低于 3 英里半径,但我也不会将注释触摸到屏幕的一侧。此外,我还希望注释一旦缩放到 self.view 的下半部分(我的地图占据了整个屏幕)。
我尝试了以下两种方法,但都不起作用。
// #1 ///// 总是在德克萨斯州放大以显示我的注释,缩小到很远我什至看不到美国各州
-(void)zoomToFitMapAnnotations:(MKMapView*)aMapView {
if([aMapView.annotations count] == 0) {
return;
}
CLLocationCoordinate2D topLeftCoord;
topLeftCoord.latitude = -90;
topLeftCoord.longitude = -180;
CLLocationCoordinate2D bottomRightCoord;
bottomRightCoord.latitude = 90;
bottomRightCoord.longitude = -180;
for (id <MKAnnotation> annotation in self.mapView.annotations){
topLeftCoord.longitude = fmin(topLeftCoord.longitude, annotation.coordinate.longitude);
topLeftCoord.latitude = fmax(topLeftCoord.latitude, annotation.coordinate.latitude);
bottomRightCoord.longitude = fmax(bottomRightCoord.longitude, annotation.coordinate.longitude);
bottomRightCoord.latitude = fmin(bottomRightCoord.latitude, annotation.coordinate.latitude);
}
MKCoordinateRegion region;
region.center.latitude = topLeftCoord.latitude - (topLeftCoord.latitude - bottomRightCoord.latitude) * 0.5;
region.center.longitude = topLeftCoord.longitude + (bottomRightCoord.longitude - topLeftCoord.longitude) * 0.5;
//Add a little space on both sides
region.span.latitudeDelta = fabs(topLeftCoord.latitude - bottomRightCoord.latitude) * 1.1;
//Add a little extra space on bith sides
region.span.longitudeDelta = fabs(bottomRightCoord.longitude - topLeftCoord.longitude) * 1.1;
region = [aMapView regionThatFits:region];
[self.mapView setRegion:region animated:YES];
}
// #2 ///// 这个效果最好,但是放大很多;就在房子的顶部,如果只有一个注释,但我想查看一个注释和 4 英里半径。所以我永远不想缩放小于显示的 4 平方英里,除非用户手动缩放它。
MKMapRect zoomRect = MKMapRectNull;
for (id <MKAnnotation> annotation in self.mapView.annotations)
{
MKMapPoint annotationPoint = MKMapPointForCoordinate(annotation.coordinate);
MKMapRect pointRect = MKMapRectMake(annotationPoint.x, annotationPoint.y, 0.1, 0.1);
zoomRect = MKMapRectUnion(zoomRect, pointRect);
}
[self.mapView setVisibleMapRect:zoomRect edgePadding:UIEdgeInsetsMake(300, 300, 100, 300) animated:YES];