MapView ConcurrentModificationException

Question

由于标题暗示我有（有时）在尝试创建两个位置之间的路由时发生并发修改... 这是我的代码（并且万一您想知道MyOverlay不会尝试访问其他覆盖在地图中）

private class fillRouteTask extends AsyncTask<Void, GeoPoint, Void> { 

    /** 
    * create the url to call to get the route 
    * 
    * @param src 
    * @param dest 
    * @return 
    */ 
    private StringBuilder createUrl(GeoPoint src, GeoPoint dest) { 
    // connect to map web service 
    StringBuilder urlString = new StringBuilder(); 
    urlString.append("http://maps.google.com/maps?f=d&hl=en"); 
    urlString.append("&saddr=");// from 
    urlString.append(Double 
    .toString((double) src.getLatitudeE6()/1.0E6)); 
    urlString.append(","); 
    urlString.append(Double 
    .toString((double) src.getLongitudeE6()/1.0E6)); 
    urlString.append("&daddr=");// to 
    urlString.append(Double 
    .toString((double) dest.getLatitudeE6()/1.0E6)); 
    urlString.append(","); 
    urlString.append(Double 
    .toString((double) dest.getLongitudeE6()/1.0E6)); 
    urlString.append("&ie=UTF8&0&om=0&output=kml"); 
    Log.d("xxx", "URL=" + urlString.toString()); 

    return urlString; 
    } 

    /** 
    * create the connection to google url 
    * 
    * @param src 
    * @param dest 
    * @return 
    */ 
    private String connectToUrl(GeoPoint src, GeoPoint dest) { 

    // get the kml (XML) doc. And parse it to get the 
    // coordinates(direction 
    // route). 
    Document doc = null; 
    HttpURLConnection urlConnection = null; 
    URL url = null; 
    try { 
    url = new URL(createUrl(src, dest).toString()); 
    urlConnection = (HttpURLConnection) url.openConnection(); 
    urlConnection.setRequestMethod("GET"); 
    urlConnection.setDoOutput(true); 
    urlConnection.setDoInput(true); 
    urlConnection.connect(); 

    DocumentBuilderFactory dbf = DocumentBuilderFactory 
     .newInstance(); 
    DocumentBuilder db = dbf.newDocumentBuilder(); 
    doc = db.parse(urlConnection.getInputStream()); 

    if (doc.getElementsByTagName("GeometryCollection") != null 
     && doc.getElementsByTagName("GeometryCollection") 
     .getLength() > 0) { 
    return doc.getElementsByTagName("GeometryCollection").item(
     0).getFirstChild().getFirstChild().getFirstChild() 
     .getNodeValue(); 
    } 

    } catch (MalformedURLException e) { 
    Log.d("test", e.getLocalizedMessage()); 
    } catch (IOException e) { 
    Log.d("test", e.getLocalizedMessage()); 
    } catch (ParserConfigurationException e) { 
    Log.d("test", e.getLocalizedMessage()); 
    } catch (SAXException e) { 
    Log.d("test", e.getLocalizedMessage()); 
    } 
    return null; 
    } 

    protected Void doInBackground(Void... arg0) { 
    try { 
    // get the current overlays present in the map 
    List<Overlay> overs = Collections.synchronizedList(mapView 
     .getOverlays()); 
    String path = connectToUrl(orig, dest); 
    if (path != null) { 
    Log.d("xxx", "path=" + path); 
    String[] pairs = path.split(" "); 
    String[] lngLat = pairs[0].split(","); 

    GeoPoint startGP = new GeoPoint((int) (Double 
     .parseDouble(lngLat[1]) * 1E6), (int) (Double 
     .parseDouble(lngLat[0]) * 1E6)); 

    overs.add(new MyOverlay(startGP, startGP, 1)); 
    GeoPoint gp1; 
    GeoPoint gp2 = startGP; 
    for (int i = 1; i < pairs.length; i++) // the last one would 
    // be 
    // crash 
    { 
     lngLat = pairs[i].split(","); 
     gp1 = gp2; 
     // watch out! For GeoPoint, first:latitude, 
     // second:longitude 
     gp2 = new GeoPoint(
     (int) (Double.parseDouble(lngLat[1]) * 1E6), 
     (int) (Double.parseDouble(lngLat[0]) * 1E6)); 
     Log.d("xxx", "pair:" + pairs[i]); 
     publishProgress(gp1, gp2); 
    } 
    overs.add(new MyOverlay(dest, dest, 3)); // use 
    // the 
    // default 
    // color 
    drawn = false; 
    } else { 
    m_handler.post(new Runnable() { 

     public void run() { 
     Toast.makeText(getApplicationContext(), 
     "Problem in getting the directions", 
     Toast.LENGTH_SHORT).show(); 
     } 
    }); 
    } 
    } catch (Exception e) { 
    m_handler.post(new Runnable() { 

    public void run() { 
     Toast.makeText(getApplicationContext(), 
     R.string.errorrouteLoad, Toast.LENGTH_LONG) 
     .show(); 
    } 
    }); 
    } 
    return null; 

    } 

    /* 
    * (non-Javadoc) 
    * 
    * @see android.os.AsyncTask#onProgressUpdate(Progress[]) 
    */ 
    @Override 
    protected void onProgressUpdate(GeoPoint... values) { 
    // TODO Auto-generated method stub 
    List<Overlay> overs = Collections.synchronizedList(mapView 
    .getOverlays()); 
    overs.add(new MyOverlay(values[0], values[1], 2, 0x0000ff)); 

    } 

    /* 
    * (non-Javadoc) 
    * 
    * @see android.os.AsyncTask#onPostExecute(java.lang.Object) 
    */ 
    @Override 
    protected void onPostExecute(Void result) { 
    // TODO Auto-generated method stub 
    Log.d("routing", "done"); 
    mapView.postInvalidate(); 
    } 
} 

Answer 1

您只能在UI线程上修改叠加层。您需要将新数据添加到AsyncTask的onPostExecute方法中的叠加层。