我怎么知道MKMapview setRegion:animated:什么时候完成了？

Question

我想在我的MKMapView上设置一个区域,然后找到与地图的NE和SW角对应的坐标.

This code works just fine to do that:
//Recenter and zoom map in on search location
MKCoordinateRegion region =  {{0.0f, 0.0f}, {0.0f, 0.0f}};
region.center = mySearchLocation.searchLocation.coordinate;
region.span.longitudeDelta = 0.01f;
region.span.latitudeDelta = 0.01f;
[self.mapView setRegion:region animated:NO]; //When this is set to YES it seems to break the coordinate calculation because the map is in motion

//After the new search location has been added to the map, and the map zoomed, we need to update the search bounds
//First we need to calculate the corners of the map so we get the points
CGPoint nePoint = CGPointMake(self.mapView.bounds.origin.x + mapView.bounds.size.width, mapView.bounds.origin.y);
CGPoint swPoint = CGPointMake((self.mapView.bounds.origin.x), (mapView.bounds.origin.y + mapView.bounds.size.height));

//Then transform those point into lat,lng values
CLLocationCoordinate2D neCoord;
neCoord = [mapView convertPoint:nePoint toCoordinateFromView:mapView];
CLLocation *neLocation = [[CLLocation alloc] initWithLatitude:neCoord.latitude longitude:neCoord.longitude];

CLLocationCoordinate2D swCoord;
swCoord = [mapView convertPoint:swPoint toCoordinateFromView:mapView];
CLLocation *swLocation = [[CLLocation alloc] initWithLatitude:swCoord.latitude longitude:swCoord.longitude];

问题是我希望地图缩放动画.但是,当我将setRegion:animated设置为YES时,我最终会在地图缩小时(即动画完成之前)从地图中获取坐标.有没有办法得到动画完成的信号？

Answer 1

从未使用过mapkit,但MKMapViewDelegate有一个mapView:regionDidChangeAnimated:看起来像你正在寻找的方法.

Answer 2

我知道这是超级老,但万一其他人来寻找答案,这里是另一种选择.

关于这个版本的好处是,你可以在第一个完成动画的完整时刻运行完成动画,而不是在回调方法中猜测/硬编码,因为那个是立即调用的.

[MKMapView animateWithDuration:1.0 animations:^{
    [mapView setRegion:mapRegion animated:YES];
} completion:^(BOOL finished) {
    [UIView animateWithDuration:1.0 animations:^{
        self.mapDotsImageView.alpha = 1.0;
    }];
}];

要不就

// zoom in...
let km3:CLLocationDistance = 3000
let crTight = MKCoordinateRegionMakeWithDistance(location.coordinate, km3, km3)
MKMapView.animate(withDuration: 1.0, animations: { self.theMap.region = crTight })