為什么Google Android 4.0以上版本的地圖活動會關閉？

Question

我在Eclipse上有一個Navigation項目，想在Android Studio上運行它，它在API 10設備上運行。 當我嘗試在API 15設備上或以上運行時， MapActivity自動關閉我的應用程序。

它返回空指針異常。 我知道必須將其更改為“地圖片段”，我不知道如何更改它？

我的MapActivity Java代碼如下：-

public class NaviMap extends MapActivity {

MockLocProvider mockProvider;
ArrayList<Step> steps = new ArrayList<Step>();
Step curStep;
TextToSpeech tts;
FixedMyLocationOverlay myLoc;
MapView mv;
MapController mapcontrol;
ArrayList<GeoPoint> points = new ArrayList<GeoPoint>();
static List<Overlay> mapitems;

LocationManager lm;
Drawable dr;
Location from, to;

Context cntx;
ProgressDialog pd;
boolean lastStep = false;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    this.setContentView(R.layout.navi_map);

    from = this.getIntent().getExtras().getParcelable("from");
    to = this.getIntent().getExtras().getParcelable("to");

    lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    tts = new TextToSpeech(this, onInit);

    cntx = this;
    dr = cntx.getResources().getDrawable(R.drawable.marker);

    mv = (MapView) findViewById(R.id.interMap);
    mv.setBuiltInZoomControls(true);

    mapcontrol = mv.getController();
    mapcontrol.setZoom(20);
    mapitems = mv.getOverlays();
    myLoc = new FixedMyLocationOverlay(this, mv);

    GetJson getDir = new GetJson();
    getDir.execute();
    myLoc.enableMyLocation();
}

@Override
protected void onDestroy() {
    // TODO Auto-generated method stub
    tts.stop();
    tts.shutdown();
    mockProvider.shutdown();
    super.onDestroy();
}

@Override
protected void onPause() {
    // TODO Auto-generated method stub
    super.onPause();
    myLoc.disableMyLocation();
}

@Override
protected void onResume() {
    // TODO Auto-generated method stub
    super.onResume();
    myLoc.enableMyLocation();
}

TextToSpeech.OnInitListener onInit = new TextToSpeech.OnInitListener() {
    @Override
    public void onInit(int status) {
        // TODO Auto-generated method stub
        if(status == TextToSpeech.SUCCESS)
        {
            int res = tts.setLanguage(Locale.US);
            if(res == TextToSpeech.LANG_MISSING_DATA || 
                    res == TextToSpeech.LANG_NOT_SUPPORTED)
                Toast.makeText(cntx, "Unable to Initialize Text-to-Speech engine", Toast.LENGTH_LONG).show();
            else
                speak("Getting data, please wait", TextToSpeech.QUEUE_FLUSH);
        }
        else
            Toast.makeText(cntx, "Unable to Initialize Text-to-Speech engine", Toast.LENGTH_LONG).show();
    }
};

LocationListener locListen = new LocationListener(){

    @Override
    public void onLocationChanged(Location loc) {
        // TODO Auto-generated method stub
        GeoPoint point = new GeoPoint((int) ((loc.getLatitude()) * 1E6),
                (int) ((loc.getLongitude()) * 1E6));
        mapcontrol.animateTo(point);
        float distance = loc.distanceTo(curStep.getEnd());
        if(distance <= 2) // reached next step
        {
            if(lastStep) //  reached destination
                speak("Reached your destination", TextToSpeech.QUEUE_FLUSH);
            else // move to next step
            {
                curStep = steps.get(0);
                steps.remove(0);
                if(steps.size() == 0)
                    lastStep = true;
                speak(curStep.getInstruction(), TextToSpeech.QUEUE_FLUSH);
                float dist = curStep.getDistance();
                String mval;
                if(curStep.getDistance() < 1000 )
                    mval = "Meters";
                else
                {
                    dist /= 1000;
                    mval = "Kilo meteres";
                }
                speak("Next step in " + dist + mval, TextToSpeech.QUEUE_ADD);
            }
        }
    }

    @Override
    public void onProviderDisabled(String provider) {}

    @Override
    public void onProviderEnabled(String provider) {}

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {}
};

@Override
protected boolean isRouteDisplayed() {
    // TODO Auto-generated method stub
    return false;
}

public class InterMapOverlay extends Overlay {

    @Override
    public void draw(Canvas canvas, MapView mapview, boolean shadow) {
        // TODO Auto-generated method stub
        super.draw(canvas, mapview, false);
        drawPath(mapview, canvas);
    }

    public void drawPath(MapView mv, Canvas cv) {

        int xp=-1, yp=-1, xn=-1, yn=-1;
        Paint paint = new Paint();
        paint.setColor(Color.BLUE);
        paint.setStyle(Paint.Style.FILL_AND_STROKE);
        paint.setStrokeWidth(5);
        paint.setAlpha(100);
        if(points != null)
        {
            for(int i = 0; i < points.size(); i++)
            {
                GeoPoint curPoint = points.get(i);
                Point point = new Point();
                mv.getProjection().toPixels(curPoint, point);
                xn = point.x;
                yn = point.y;
                if( xp != -1 )
                    cv.drawLine(xp, yp, xn, yn, paint);
                xp = xn;
                yp = yn;
            }
        }
    }       
}

public ArrayList<GeoPoint> decodePoly(String encoded) {

    ArrayList<GeoPoint> poly = new ArrayList<GeoPoint>();
    int index = 0, len = encoded.length();
    int lat = 0, lng = 0;

    while (index < len) {
        int b, shift = 0, result = 0;
        do {
            b = encoded.charAt(index++) - 63;
            result |= (b & 0x1f) << shift;
            shift += 5;
        } while (b >= 0x20);
        int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
        lat += dlat;

        shift = 0;
        result = 0;
        do {
            b = encoded.charAt(index++) - 63;
            result |= (b & 0x1f) << shift;
            shift += 5;
        } while (b >= 0x20);
        int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
        lng += dlng;

        GeoPoint p = new GeoPoint((int) (((double) lat / 1E5) * 1E6),
                (int) (((double) lng / 1E5) * 1E6));
        poly.add(p);
    }
    return poly;
}

public class GetJson extends AsyncTask<Void, Address, Void>
{
    @Override
    protected void onPreExecute() {
        // TODO Auto-generated method stub
        points.clear();
        mapitems.clear();

        pd = new ProgressDialog(cntx);
        pd.setCancelable(false);
        pd.setMessage("Getting routes...");
        pd.setProgressStyle(ProgressDialog.STYLE_SPINNER);
        pd.show();
    }

    @Override
    protected Void doInBackground(Void... arg0) {
        // TODO Auto-generated method stub
        String url = "http://maps.googleapis.com/maps/api/directions/json?origin=" + from.getLatitude() + "," + from.getLongitude() +
                "&destination=" + to.getLatitude() + "," + to.getLongitude() + "&sensor=true&units=metric&mode=walking";
        try {
            HttpClient cli = new DefaultHttpClient();
            HttpPost post = new HttpPost(url);
            HttpResponse res = cli.execute(post);
            InputStream in = res.getEntity().getContent();
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    in, "iso-8859-1"), 8);
            StringBuilder sb = new StringBuilder();
            sb.append(reader.readLine() + "\n");
            String line = "0";
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            }
            in.close();
            reader.close();

            // decoding JSON data..
            JSONObject obj = new JSONObject(sb.toString());
            JSONArray array = obj.getJSONArray("routes");
            JSONObject routes = array.getJSONObject(0);
            JSONObject route_polyline = routes.getJSONObject("overview_polyline");
            String encoded = route_polyline.getString("points");
            points = decodePoly(encoded);

            // getting STEPS details...
            JSONArray legs = routes.getJSONArray("legs");
            JSONObject leg1 = legs.getJSONObject(0);
            JSONArray jsteps = leg1.getJSONArray("steps");
            for(int i = 0; i < jsteps.length(); i++)
            {
                JSONObject jstep = jsteps.getJSONObject(i);
                Step step = new Step();
                // getting distance
                JSONObject jdis = jstep.getJSONObject("distance");
                step.setDistance(jdis.getInt("value"));
                // getting duration
                JSONObject jdur = jstep.getJSONObject("duration");
                step.setDuration(jdur.getInt("value") / 60);
                // getting instruction
                step.setInstruction(Html.fromHtml(jstep.getString("html_instructions")).toString());
                // getting starting point
                JSONObject jstart = jstep.getJSONObject("start_location");
                Location start = new Location(LocationManager.NETWORK_PROVIDER);
                start.setLatitude(jstart.getDouble("lat"));
                start.setLongitude(jstart.getDouble("lng"));
                step.setStart(start);
                // getting end point
                JSONObject jend = jstep.getJSONObject("end_location");
                Location end = new Location(LocationManager.NETWORK_PROVIDER);
                end.setLatitude(jend.getDouble("lat"));
                end.setLongitude(jend.getDouble("lng"));
                step.setEnd(end);
                steps.add(step);
            }
        }
        catch(Exception e) {
            e.printStackTrace();
            speak("Unable to get Route data", TextToSpeech.QUEUE_ADD);
        }
    return null;
}

    @Override
    protected void onPostExecute(Void result) {
        // TODO Auto-generated method stub]
        mapcontrol.animateTo(points.get(0));
        StageOverlay stageOverlay = new StageOverlay(dr, cntx);
        stageOverlay.addOverlay(new OverlayItem(points.get(0), "Source", "Source"));
        stageOverlay.addOverlay(new OverlayItem(points.get(points.size() - 1), "Destination", "Destination"));
        mapitems.add(stageOverlay);
        mapitems.add(new InterMapOverlay());
        mapitems.add(myLoc);
        mv.postInvalidate();
        mv.invalidate();
        pd.dismiss();
        curStep = steps.get(0);
        steps.remove(0);
        if(steps.size() == 0)
            lastStep = true;
        speak("Start walking by Instruction, " + curStep.getInstruction(), TextToSpeech.QUEUE_ADD);
        speak("Next step in " + curStep.getDistance() + " meters", TextToSpeech.QUEUE_ADD);
        //lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locListen);
        //lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locListen);
        mockProvider = new MockLocProvider(LocationManager.NETWORK_PROVIDER, cntx, points);
        lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locListen);
        mockProvider.start();
    }
}

private void speak(String text, int Mode)
{
    tts.speak(text, Mode, null);
}
}

XML代碼如下：-

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >

<com.google.android.maps.MapView
    android:id="@+id/interMap"
    android:clickable="true"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:apiKey="0QhmZ8LxWHMvKv6YNSv0kAD87EE7xXRzW4EamFg" />

   </RelativeLayout>

清單文件如下：

    <?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="mani.droid.blindnavigation"
     android:versionCode="1"
     android:versionName="1.0" >

  <uses-sdk
    android:minSdkVersion="10"
    android:targetSdkVersion="17" />

   <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
   <uses-permission android:name="android.permission.INTERNET"/>
   <uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION"/>

     <application
     android:allowBackup="true"
     android:icon="@drawable/ic_launcher"
     android:label="@string/app_name"
     android:theme="@style/AppTheme" >

    <uses-library android:name="com.google.android.maps" />

    <activity
        android:name="mani.droid.blindnavigation.HomeActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity android:name=".NaviMap" />
     </application>

     </manifest>

Answer 1

在清單中添加此權限：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />