MKMapView - 限制地图滚动到正方形叠加层

Question

我有一个带有方形覆盖的MKMapView，描述为：

   CLLocationCoordinate2D coordsBg[5]={
    CLLocationCoordinate2DMake(31.750865,35.180882),
    CLLocationCoordinate2DMake(31.740331,35.180882),
    CLLocationCoordinate2DMake(31.740331,35.165452),
    CLLocationCoordinate2DMake(31.750865,35.165452),
    CLLocationCoordinate2DMake(31.750865,35.180882)
};     
MKPolygon *bg=[MKPolygon polygonWithCoordinates:coordsBg count:5];
[map addOverlay:bg];

我希望限制用户在覆盖层之外滚动。

我可以为此限制 MKMapView 滚动视图吗？还是有其他方法？

谢谢

沙尼

Answer 1

经过几个小时的敲打，我得到了这个对我有用的解决方案。

它混淆了：

这篇文章：设置 mkmapview 的缩放级别

和这个链接：限制 mkmapview 从@Anna卡列尼娜评论滚动到我的问题。

这是我的代码：

- (void)mapView:(MKMapView *)mapView regionWillChangeAnimated:(BOOL)animated
{
    lastGoodMapRect = mapView.visibleMapRect;
    lastGoodRegion = mapView.region;
}
- (void)mapView:(MKMapView *)mapView regionDidChangeAnimated:(BOOL)animated
{
    if (manuallyChangingMapRect) {
        manuallyChangingMapRect=NO;
        return;
    }
    if( [mapView zoomLevel] > 16 )
    {
        [mapView setCenterCoordinate:lastGoodRegion.center zoomLevel:16 animated:YES];
    }
    MKMapRect visibleRect = mapView.visibleMapRect;
    MKMapRect OverlayRect = bg.boundingMapRect;
    MKMapRect intersectionRect = MKMapRectIntersection(visibleRect,OverlayRect);
    //you can change the min and max zoom off course
    if(!MKMapRectEqualToRect(visibleRect,intersectionRect)){
        if( [mapView zoomLevel] < 15){
            [mapView setCenterCoordinate:lastGoodRegion.center zoomLevel:15 animated:YES];
        }else if( [mapView zoomLevel] > 16 )
        {
            [mapView setCenterCoordinate:lastGoodRegion.center zoomLevel:16 animated:YES];
        }else{
            manuallyChangingMapRect=YES;
            [mapView setVisibleMapRect:lastGoodMapRect animated:YES];
        }
    }
}