Question

我在Android中实现OpenStreetMap MapView时遇到了问题。我正在使用OsmDroid库：问题是当我点击智能手机退出按钮（中心）后恢复应用程序或单击最近的应用程序按钮时，未显示地图，并且视图在黑屏中停止。没有显示ANR。在logcat中没有异常消息。没有打印异常。只有一个黑屏。

有什么问题？我试图调试应用程序，但我没有发现异常。这是代码：

package it.presenteapp.ui;

import it.presenteapp.R;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.drawable.Drawable;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;

import android.view.Menu;
import android.view.MenuItem;
import android.view.View;

import android.widget.TextView;
import android.widget.Toast;

import org.osmdroid.DefaultResourceProxyImpl;
import org.osmdroid.api.IGeoPoint;

import org.osmdroid.tileprovider.tilesource.TileSourceFactory;

import org.osmdroid.util.GeoPoint;

import org.osmdroid.views.MapView;
import org.osmdroid.views.overlay.ItemizedIconOverlay;
import org.osmdroid.views.overlay.MinimapOverlay;
import org.osmdroid.views.overlay.OverlayItem;
import org.osmdroid.views.overlay.PathOverlay;
import org.osmdroid.views.overlay.ScaleBarOverlay;
import org.osmdroid.views.overlay.compass.CompassOverlay;
import org.osmdroid.views.overlay.mylocation.MyLocationNewOverlay;


import java.util.ArrayList;
import java.util.Timer;
import java.util.TimerTask;

import it.presenteapp.network.NetworkResource;
import it.presenteapp.network.classForJSON.RouteResponse;
import it.presenteapp.utils.Config;

public class MapActivity extends Activity
{
    private MapView mOsmv;
    private Timer timerTask;
    private boolean networkProviderEnabled;
    private RouteResponse Route;
    private GeoPoint currentLocation;

    private Boolean doBackground =false;

    private MyLocationNewOverlay partenza;
    private GeoPoint arrivo;
    private PathOverlay pathOverlay;
    private Paint paint;
    private MinimapOverlay miniMapOverlay;
    private ScaleBarOverlay scaleBar;
    private CompassOverlay compassOverlay;

    private String nomeCognome;




    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_map);

        this.mOsmv = (MapView)findViewById(R.id.mapview);

        Intent i=getIntent();
        this.nomeCognome = i.getStringExtra("NomeCognome");
        this.arrivo= new GeoPoint(i.getDoubleExtra("Latitudine",43.6156683),i.getDoubleExtra("Longitudine",13.5177356));

        getActionBar().setTitle("Ricerca loculo: "+ nomeCognome);



    }

    @Override
    protected void onResume()
    {
        super.onResume();
        Log.e("MAPACTIVITY", "RESUME CALLED");

        this.mOsmv.setTileSource(TileSourceFactory.CYCLEMAP);
        this.mOsmv.setUseDataConnection(true);
        this.mOsmv.setBuiltInZoomControls(true);
        this.mOsmv.setMultiTouchControls(true);
        this.mOsmv.setMinZoomLevel(4);
        this.mOsmv.getController().setZoom(this.mOsmv.getMaxZoomLevel());

        Log.e("1", "ok");
        /* setto il marker di arrivo */
        Drawable markerArrivo = this.getResources().getDrawable(R.drawable.arrivo);
        ArrayList listItem = new ArrayList<OverlayItem>();
        final OverlayItem itemArrivo = new OverlayItem(this.nomeCognome, "nato il "+ "\n"+ "morto il ", arrivo);
        itemArrivo.setMarker(markerArrivo);
        listItem.add(itemArrivo);
        this.mOsmv.getOverlayManager().clear();
        this.mOsmv.getOverlayManager().add(new ItemizedIconOverlay<OverlayItem>(listItem, new ItemizedIconOverlay.OnItemGestureListener<OverlayItem>() {
            @Override
            public boolean onItemSingleTapUp(int index, OverlayItem item) {
                Toast.makeText(getApplicationContext(),itemArrivo.getTitle()+"\n"+itemArrivo.getSnippet(),Toast.LENGTH_SHORT).show();
                return false;
            }

            @Override
            public boolean onItemLongPress(int index, OverlayItem item) {
                //Toast.makeText(getApplicationContext(),"LUUUNGO",Toast.LENGTH_SHORT).show();
                return false;
            }
        }, new DefaultResourceProxyImpl(getApplicationContext())));
        Log.e("2", "ok");
        /* setto il marker di partenza/attuale posizione dell'utente */
        partenza = new MyLocationNewOverlay(getApplicationContext(),this.mOsmv);
        partenza.enableFollowLocation();
        partenza.enableMyLocation();

        this.mOsmv.getOverlayManager().add(partenza);
        Log.e("3", "ok");
        /* aggiungo la scala della mappa */
        scaleBar = new ScaleBarOverlay(this.getBaseContext(), this.mOsmv.getResourceProxy());
        scaleBar.setCentred(true);
        this.mOsmv.getOverlayManager().add(scaleBar);

        Log.e("4", "ok");
        /* aggiungo la bussola della mappa */
        compassOverlay = new CompassOverlay(this, this.mOsmv);
        compassOverlay.enableCompass();
        this.mOsmv.getOverlayManager().add(compassOverlay);
        Log.e("5", "ok");
        /* aggiungo la mini mappa */
        miniMapOverlay = new MinimapOverlay(this, this.mOsmv.getTileRequestCompleteHandler());
        this.mOsmv.getOverlayManager().add(miniMapOverlay);
        Log.e("6", "ok");
        /* setto le proprietà del disegno della rotta */
        this.paint = new Paint();
        paint.setColor(Color.BLUE);
        paint.setAlpha(100);
        paint.setStyle(Paint.Style.STROKE);
        paint.setStrokeWidth(8);
        Log.e("7", "ok");
        /* inizializzo il routing via Graphopper */
        this.startGraphopperTask();
        Log.e("9", "ok");
    }

    @Override
    protected void onPause() {
        super.onPause();

        Log.e("MAPACTIVITY","PAUSE CALLED");

        this.timerTask.cancel();
        this.mOsmv.setBuiltInZoomControls(false);
        setVisible(false);
        this.partenza.disableMyLocation();
        this.partenza.disableFollowLocation();
        this.mOsmv.getTileProvider().detach();

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.map, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        switch (item.getItemId())
        {
            case R.id.action_shortcut_map_credits:
                Toast.makeText(this,"@ Univpm", Toast.LENGTH_SHORT).show();
                return true;

            case android.R.id.home:
                onBackPressed();
                return true;

            default:
                Log.e("premuto","altro");
        }
        return super.onOptionsItemSelected(item);
    }


    @Override
    protected void onDestroy()
    {
        Log.e("MAPACTIVITY","DESTROY CALLED");
        super.onDestroy();
    }

    public void drawRoute(RouteResponse _Route)
    {
        if(this.pathOverlay != null)
            this.mOsmv.getOverlayManager().remove(this.pathOverlay);

        Log.e("new position","setted!");

        PathOverlay newPathOverlay = new PathOverlay(Color.RED,MapActivity.this);
        newPathOverlay.addPoints(_Route.getPaths()[0].getPoints().getCoordinatesGeoPoint());
        newPathOverlay.setPaint(this.paint);

        this.mOsmv.getOverlays().add(newPathOverlay);
        this.pathOverlay = newPathOverlay;

        TextView istruzioni= (TextView) findViewById(R.id.popup_ins);
        istruzioni.setText(_Route.getPaths()[0].getInstructions()[0].getText());
        istruzioni.setVisibility(TextView.VISIBLE);

        doBackground=false;

    }
    public void centerPosition(View v)
    {
        this.mOsmv.getController().animateTo((IGeoPoint) partenza.getMyLocation());
        while (true)
        {
            if (!this.mOsmv.isAnimating())
            {
                this.mOsmv.getController().setZoom(this.mOsmv.getMaxZoomLevel());
                return;
            }

        }
    }
    private class GraphopperTask extends AsyncTask<Void, Void, Void>
    {
        RouteResponse puntiRotta;

        @Override
        protected void onPreExecute()
        {
            Log.e("task ricerc route", "partito!");
            super.onPreExecute();
            // before making http calls

        }

        @Override
        protected Void doInBackground(Void... arg0)
        {

            NetworkResource net =new NetworkResource();
            if(partenza.getMyLocation() != null)
            {
                try {
                    Log.e("FASE PRE-CHIAMATA ROUTE", "CORRETTA");
                    String StartPoint = new StringBuilder().append(partenza.getMyLocation().getLatitudeE6() / 1E6).append(",")
                            .append(partenza.getMyLocation().getLongitudeE6() / 1E6).toString();
                    String EndPoint = new StringBuilder().append(arrivo.getLatitudeE6() / 1E6).append(",")
                            .append(arrivo.getLongitudeE6() / 1E6).toString();
                    puntiRotta = net.getRoute(StartPoint, EndPoint);
                    Log.e("StartPoint", StartPoint);
                    Log.e("EndPoint", EndPoint);
                    Log.e("FASE PARSING ROUTE", "CORRETTA");
                } catch (Exception e) {
                    Log.e("ERRORE", e.toString());
                }
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void result)
        {
            super.onPostExecute(result);
            // After completing http call
            // will close this activity and launch main activity
            Route=puntiRotta;
            drawRoute(Route);
        }

    }

    private void startGraphopperTask()
    {
        final Handler handler = new Handler();
        this.timerTask = new Timer();
        TimerTask doAsynchronousTask = new TimerTask()
        {
            @Override
            public void run()
            {
                handler.post(new Runnable()
                {
                    public void run()
                    {
                        try
                        {
                            if(partenza.getMyLocation() != null)
                            {
                                GraphopperTask graphopperTask = new GraphopperTask();
                                // PerformBackgroundTask this class is the class that extends AsynchTask

                                graphopperTask.execute();
                            }
                        } catch (Exception e)
                        {

                        }
                    }
                });
            }
        };
        this.timerTask.schedule(doAsynchronousTask, Config.startRouteDelay, Config.updateRouteInterval);
        Log.e("8", "ok");
    }

}

Answer 1

问题是你在onPause（）中调用setVisible（false），而在onResume（）中没有调用setVisibile（true）。考虑到在这种情况下你不需要使用setVisible（bool）方法;根据Android文档（链接）：

public void setVisible（boolean visible）在API级别3 Control中添加此活动的主窗口是否可见。这仅供参考对于不会显示UI的活动的特殊情况本身，但不能只是在onResume（）之前完成，因为它需要等待服务绑定等。将此设置为false允许您防止在此期间显示您的UI。默认这个值来自于windowNoDisplay属性活动的主题。

使用OsmDroid的MapView中的黑屏

1 个答案: