防止在谷歌地图上滚动外部地图区域 [英] Prevent scrolling outside map area on google map

问题描述

实际上，我正在处理Google Maps Framework for iOS，并且我想阻止向给定区域滚动。

我一开始试图做的，实现委托方法： - （void）mapView：（GMSMapView *）mapView didChangeCameraPosition：（GMSCameraPosition *）position 并将地图位置与右/左角比较。滚动或缩放时遇到很多问题。

下面是我执行的例子：

   - （void） mapView：（GMSMapView *）mapView didChangeCameraPosition：（GMSCameraPosition *）position {
 
 if（position.target.latitude> topLat）{
 GMSCameraPosition * goBackCamera = [GMSCameraPosition cameraWithLatitude：topLat 
 longitude：position.target.longitude 
 zoom：position.zoom 
 bearing：220 
 viewingAngle：0]; 
 
 [self.mapView animateToCameraPosition：goBackCamera]; 
} 
 
 if（position.target.latitude< bottomLat）{
 GMSCameraPosition * goBackCamera = [GMSCameraPosition cameraWithLatitude：bottomLat 
 longitude：position.target.longitude 
 zoom：position.zoom 
 bearing：220 
 viewingAngle：0]; 
 [self.mapView animateToCameraPosition：goBackCamera]; 
} 
 
 if（position.target.longitude> rightLong）{
 GMSCameraPosition * goBackCamera = [GMSCameraPosition cameraWithLatitude：position.target.latitude 
 longitude：rightLong 
 zoom：position.zoom 
 bearing：220 
 viewingAngle：0]; 
 [self.mapView animateToCameraPosition：goBackCamera]; 
} 
 
 if（position.target.longitude  GMSCameraPosition * goBackCamera = [GMSCameraPosition cameraWithLatitude：position.target.latitude 
 longitude：leftLong 
 zoom：position.zoom 
 bearing：220 
 viewingAngle：0]; 
 [self.mapView animateToCameraPosition：goBackCamera]; 
 
 
 
 
 $ b $ p 
 
你有没有办法更有效地处理这个问题？
 
 
 
 PS：TopLat，RightLong ...表示上纬度和右经度等。
 
 
 
问候
解决方案
使用GMSCoordinateBounds（东北坐标，西南坐标）方法。 
这可能有帮助
  GMSCoordinateBounds类参考 
 
Am actually dealing with the Google Maps Framework for iOS, and I want to block scrolling out side a giving area.

What I tried to do at first, implement the delegate method : - (void)mapView:(GMSMapView *)mapView didChangeCameraPosition:(GMSCameraPosition *)position and compare the map position with the right/left corners.But what I did has many issues when scrolling or zooming. 

Below an exemple of my implementation : 
 - (void)mapView:(GMSMapView *)mapView didChangeCameraPosition:(GMSCameraPosition *)position {  

    if (position.target.latitude > topLat) { 
        GMSCameraPosition *goBackCamera = [GMSCameraPosition cameraWithLatitude:topLat
                                                                      longitude:position.target.longitude
                                                                            zoom:position.zoom
                                                                            bearing:220
                                                                            viewingAngle:0];

        [self.mapView animateToCameraPosition:goBackCamera];
    }

    if (position.target.latitude < bottomLat) {
        GMSCameraPosition *goBackCamera = [GMSCameraPosition cameraWithLatitude:bottomLat
                                                                      longitude:position.target.longitude
                                                                           zoom:position.zoom
                                                                        bearing:220
                                                                   viewingAngle:0];
        [self.mapView animateToCameraPosition:goBackCamera];
    }

    if (position.target.longitude > rightLong) {
        GMSCameraPosition *goBackCamera = [GMSCameraPosition cameraWithLatitude:position.target.latitude
                                                                      longitude:rightLong
                                                                           zoom:position.zoom
                                                                        bearing:220
                                                                   viewingAngle:0];
        [self.mapView animateToCameraPosition:goBackCamera];
    }

    if (position.target.longitude < leftLong) {
        GMSCameraPosition *goBackCamera = [GMSCameraPosition cameraWithLatitude:position.target.latitude
                                                                      longitude:leftLong
                                                                           zoom:position.zoom
                                                                        bearing:220
                                                                   viewingAngle:0];
        [self.mapView animateToCameraPosition:goBackCamera];
    }
}
Do you no a way more efficient to deal with this?

PS: TopLat, RightLong ... mean top Latitude and Right longitude etc 

Regards
解决方案
Use GMSCoordinateBounds(northeast co-ordinates, southwest co-ordinates) method.
This might be helpful
GMSCoordinateBounds Class Reference

                        
这篇关于防止在谷歌地图上滚动外部地图区域的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！