Maps API在animateTo()方法上抛出NullPointerException

Question

当尝试将地图动画到某个geopopoint时，我得到了一个致命的异常-这里是异常:

12-20 17:53:20.400: E/Crittercism(3523): java.lang.NullPointerException
12-20 17:53:20.400: E/Crittercism(3523): at com.amazon.geo.maps.MercatorProjection.latLongToWorldPixels(MercatorProjection.java:397)
12-20 17:53:20.400: E/Crittercism(3523): at com.amazon.geo.maps.MercatorProjection.toPixels(MercatorProjection.java:69)
12-20 17:53:20.400: E/Crittercism(3523): at com.amazon.geo.maps.MapView.animateTo_AmazonInternal(MapView.java:1801)
12-20 17:53:20.400: E/Crittercism(3523): at com.amazon.geo.maps.MapController.animateTo(MapController.java:46)
12-20 17:53:20.400: E/Crittercism(3523): at com.fatattitude.myapplication.MyMapActivity.moveMapToPoint(BusMapActivity.java:1564)

这是我的代码。我的日志输出还显示，GeoPoint的值为LatitudeE6= 51537141和 longitude = -246271

private void moveMapToPoint(GeoPoint gp, int zoomLevel) {
MapController mc = mapView.getController();
if (zoomLevel < 0)
zoomLevel = mapView.getZoomLevel();
mc.stopAnimation(true);
mc.setZoom(zoomLevel);
String strGeoPointInfo = String.format("Lat:%d, Lng:%d", gp.getLatitudeE6(), gp.getLongitudeE6() );
Log.i("GeoPoint-Info", "**moveMapToPoint: " + strTestOutput);
mc.animateTo(gp);
}

如果我注释

//mc.stopAnimation(true);

我不再得到异常。

谁能帮我理解为什么会出现这个异常?

请帮帮我。

Answer 1

应用程序很可能在GPS传感器寻找位置之前等待。

mMyLocationOverlay.runOnFirstFix(new Runnable() { 
    public void run() {
                    mapView.getController().animateTo(myLocation);
        }});