Issue
Can I limit the Google Maps V2 (Android) at 180° / -180° longitude (like iOS MapKit)? I don't want it to wrap around, as I'm trying to implement a clusterin algorithm, and the 180 / -180 degree split would make it difficult.
I would like the panning to be limited at the red line:

Solution
So I created a solution that should be fine. If the user panns the map across the -180 / 180 border, the map will flip to the other side. So wrapping the map is still possible, but the "dangerous" area is never displayed.
I had to create a custom MapView:
public class CustomMapView extends MapView {
private double prevLongitude;
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
boolean retVal = correctCamera();
prevLongitude = getMap().getCameraPosition().target.longitude;
return retVal;
}
public boolean correctCamera() {
if (getMap().getProjection().getVisibleRegion().latLngBounds.northeast.longitude < getMap().getProjection().getVisibleRegion().latLngBounds.southwest.longitude) {
double diff = getMap().getProjection().getVisibleRegion().latLngBounds.southwest.longitude - getMap().getProjection().getVisibleRegion().latLngBounds.northeast.longitude;
double longitudeSW;
double longitudeNE;
double longitudeDiff = (360-diff) / 25;
// use > 0 if you want the map to jump to the other side
// <= 0 will cause the map to flip back
if (prevLongitude > 0) {
longitudeSW = -180 + longitudeDiff;
longitudeNE = -180 + longitudeDiff - diff;
} else {
longitudeSW = 180 - longitudeDiff + diff;
longitudeNE = 180 - longitudeDiff;
}
LatLngBounds bounds = new LatLngBounds(
new LatLng(getMap().getCameraPosition().target.latitude, longitudeSW),
new LatLng(getMap().getCameraPosition().target.latitude, longitudeNE)
);
getMap().animateCamera(CameraUpdateFactory.newLatLngBounds(bounds, 0));
return true;
}
return false;
}
}
And the xml:
<com.ieffects.clustermap.CustomMapView
android:id="@+id/map"
android:layout_width="match_parent"
android:layout_height="match_parent" />
And for the GoogleMap (mapView.getMap()):
map.setOnCameraChangeListener(new OnCameraChangeListener() {
@Override
public void onCameraChange(CameraPosition position) {
mapView.correctCamera();
}
});
This is needed if the user let's the map "fly" into the dangerous region.
Answered By - D-32
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