如何在不更改用户设置的缩放比例的情况下更新地图标记？

Posted 2023-04-14

【中文标题】如何在不更改用户设置的缩放比例的情况下更新地图标记？

【英文标题】：How do I update the map marker without changing the zoom that the user has set?

【发布时间】：2013-03-11 04:01:38

【问题描述】：

我正在构建一个使用带有位置监听器的 Google 地图的 android 应用。当地图第一次出现时，我在位置监听器中将缩放设置为 12，我在谷歌地图开发方面相当新，所以我想知道一旦用户捏住以更改缩放，我如何在不影响缩放的情况下更新位置？下面是我的位置监听器。

/**
 *Mylocationlistener class will give the current GPS location 
 *with the help of Location Listener interface 
 */
private class Mylocationlistener implements LocationListener 

    @Override
    public void onLocationChanged(Location location) 

        if (location != null) 
            // ---Get current location latitude, longitude---

            Log.d("LOCATION CHANGED", location.getLatitude() + "");
            Log.d("LOCATION CHANGED", location.getLongitude() + "");
            currentLocation = new LatLng(location.getLatitude(), location.getLongitude());
            currentLatLng = new LatLng(location.getLatitude(), location.getLongitude());
            Marker currentLocationMarker = map.addMarker(new MarkerOptions().position(currentLocation).title("Current Location"));
            // Move the camera instantly to hamburg with a zoom of 15.
            map.moveCamera(CameraUpdateFactory.newLatLngZoom(currentLatLng, 15));
            // Zoom in, animating the camera.
            map.animateCamera(CameraUpdateFactory.zoomTo(12), 2000, null);
            if (!firstPass)
                currentLocationMarker.remove();
            
            firstPass = false;
            Toast.makeText(MapViewActivity.this,"Latitude = "+
                    location.getLatitude() + "" +"Longitude = "+ location.getLongitude(),
                    Toast.LENGTH_LONG).show();

        
    

【参考方案1】：

您可以在侦听器中添加一个局部变量，并使用它仅缩放第一个位置。代码如下所示：

private class Mylocationlistener implements LocationListener 

   private boolean zoomed = false;

   @Override
   public void onLocationChanged(Location location) 

    if (location != null) 
        // ---Get current location latitude, longitude---

        Log.d("LOCATION CHANGED", location.getLatitude() + "");
        Log.d("LOCATION CHANGED", location.getLongitude() + "");
        currentLocation = new LatLng(location.getLatitude(), location.getLongitude());
        currentLatLng = new LatLng(location.getLatitude(), location.getLongitude());
        Marker currentLocationMarker = map.addMarker(new MarkerOptions().position(currentLocation).title("Current Location"));
        // Move the camera instantly to hamburg with a zoom of 15.
        map.moveCamera(CameraUpdateFactory.newLatLngZoom(currentLatLng, 15));
        // Zoom in, animating the camera.
        if (!zoomed) 
            map.animateCamera(CameraUpdateFactory.zoomTo(12), 2000, null);
            zoomed = true;
                                               
        if (!firstPass)
            currentLocationMarker.remove();
        
        firstPass = false;
        Toast.makeText(MapViewActivity.this,"Latitude = "+
                location.getLatitude() + "" +"Longitude = "+ location.getLongitude(),
                Toast.LENGTH_LONG).show();

    

【参考方案2】：

尝试使用这个：

map.animateCamera(CameraUpdateFactory.newLatLngZoom(currentLocationMarker.getPosition(), map.getCameraPosition().zoom));

【讨论】：

你一定是新手。这是几年前回答的。