爲什麼縮放不適用於Google地圖？

Question

我正在關注本教程enter link description here。問題是mapView.setBuiltInZoomControls(true)完全不起作用......但是當我使用mapView.setClickable(true)時，它就起作用了。然後我的onTouch..方法不會啓動。這是完整的代碼。

package com.emazdoor.gpsmap; 

import java.util.List; 

import android.app.AlertDialog; 
import android.content.Context; 
import android.content.DialogInterface; 
import android.graphics.BitmapFactory; 
import android.graphics.Canvas; 
import android.graphics.Point; 
import android.location.Location; 
import android.location.LocationListener; 
import android.location.LocationManager; 
import android.os.Bundle; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.view.MotionEvent; 
import android.widget.Toast; 

import com.google.android.maps.GeoPoint; 
import com.google.android.maps.MapActivity; 
import com.google.android.maps.MapController; 
import com.google.android.maps.MapView; 
import com.google.android.maps.Overlay; 

public class GPSMap_Activity extends MapActivity { 

    private LocationManager locationManager; 
    public MyLocationListener locationListener; 
    private MapView mapView; 
    private MapController mapcontroller; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_gpsmap_); 
     mapView = (MapView) findViewById(R.id.mapview); 
     mapcontroller = mapView.getController(); 
     mapView.setBuiltInZoomControls(true); 
//  mapView.setClickable(true); 


     String coordinates[] = { "30", "71" }; 
     double latitude = Double.parseDouble(coordinates[0]); 
     double longitude = Double.parseDouble(coordinates[1]); 

     GeoPoint p = new GeoPoint((int) (latitude * 1E6), 
       (int) (longitude * 1E6)); 

     mapcontroller.animateTo(p); 
     mapcontroller.setZoom(7); 
     mapView.invalidate(); 

     locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); 
     locationListener = new MyLocationListener(); 
     locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 
       0, locationListener); 

    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     getMenuInflater().inflate(R.menu.menu, menu); 
     return true; 
    } 

    @Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     switch (item.getItemId()) { 
     case R.id.my_location: 
      Toast.makeText(GPSMap_Activity.this, "Moving to current Location", 
        Toast.LENGTH_LONG).show(); 
      locationListener.gpsCurrentLocation(); 
      return true; 
     case R.id.mapview_setellite: 
      Toast.makeText(GPSMap_Activity.this, "Satellite View", 
        Toast.LENGTH_LONG).show(); 
      if (mapView.isSatellite() == false) 
       mapView.setSatellite(true); 
      return true; 
     case R.id.mapview_normal: 
      Toast.makeText(GPSMap_Activity.this, "Normal View", 
        Toast.LENGTH_LONG).show(); 
      if (mapView.isSatellite() == true) 
       mapView.setSatellite(false); 
      return true; 
     } 
     return super.onOptionsItemSelected(item); 
    } 

    @Override 
    protected boolean isRouteDisplayed() { 

     return false; 
    } 


    @Override 
    public boolean onTouchEvent(MotionEvent event) { 
     if (event.getAction() == 1) { 
      GeoPoint p = mapView.getProjection().fromPixels((int) event.getX(), 
        (int) event.getY()); 
      Toast.makeText(GPSMap_Activity.this, 
        p.getLatitudeE6()/1E6 + " " + p.getLongitudeE6()/1E6, 
        Toast.LENGTH_LONG).show(); 
     } 
     return true; 
    } 

    public class MyLocationListener implements LocationListener { 

     private double tempLatitude, tempLongitude; 


     public void onLocationChanged(Location location) { 
      location.getLatitude(); 
      location.getLatitude(); 
      String text = "My current Location is:" + " Latitude= " 
        + location.getLatitude() + " Longitude= " 
        + location.getLongitude(); 

      Toast.makeText(GPSMap_Activity.this, text, Toast.LENGTH_LONG) 
        .show(); 

      if (location.getLatitude() == 71) { 
       AlertDialog.Builder alertBox = new AlertDialog.Builder(
         GPSMap_Activity.this); 
       alertBox.setMessage("You have Entered in wrong place"); 
       alertBox.setNeutralButton("OK", 
         new DialogInterface.OnClickListener() { 


          public void onClick(DialogInterface dialog, 
            int which) { 
          } 
         }); 
       alertBox.show(); 
      } 

      tempLatitude = location.getLatitude(); 
      tempLongitude = location.getLongitude(); 

      this.gpsCurrentLocation(); 
     } 

     public void gpsCurrentLocation() { 
      String coordinates[] = { "" + tempLatitude, "" + tempLongitude }; 
      double latitude = Double.parseDouble(coordinates[0]); 
      double longitude = Double.parseDouble(coordinates[1]); 

      GeoPoint p = new GeoPoint((int) (latitude * 1E6), 
        (int) (longitude * 1E6)); 

      mapcontroller.animateTo(p); 
      mapcontroller.setZoom(7); 

      MyMapOverlay marker = new MyMapOverlay(p); 
      List<Overlay> listofover = mapView.getOverlays(); 
      listofover.clear(); 
      listofover.add(marker); 

      mapView.invalidate(); 

     } 

     public void onProviderDisabled(String provider) { 
      // TODO Auto-generated method stub 

     } 

     public void onProviderEnabled(String provider) { 
      // TODO Auto-generated method stub 

     } 

     public void onStatusChanged(String provider, int status, Bundle extras) { 
      // TODO Auto-generated method stub 

     } 


    } 

    public class MyMapOverlay extends Overlay { 

     GeoPoint locationGeo = null; 

     public MyMapOverlay(GeoPoint location) { 
      this.locationGeo = location; 
     } 

     @Override 
     public void draw(Canvas canvas, MapView mapView, boolean shadow) { 
      super.draw(canvas, mapView, shadow); 

      Point screenPoint = new Point(); 
      mapView.getProjection().toPixels(this.locationGeo, screenPoint); 

      canvas.drawBitmap(BitmapFactory.decodeResource(getResources(), 
        R.drawable.ic_delete), screenPoint.x, screenPoint.y, null); 
     } 

    } 

} 

Answer 1

Use Touch Event in MapOverlay class. 


public class MyMapOverlay extends com.google.android.maps.Overlay 
{ 


      GeoPoint locationGeo = null; 


      public MyMapOverlay(GeoPoint location) 
      { 
       this.locationGeo = location; 
      } 



      @Override 
      public void draw(Canvas canvas, MapView mapView, boolean shadow) { 
       super.draw(canvas, mapView, shadow); 

       Point screenPoint = new Point(); 
       mapView.getProjection().toPixels(this.locationGeo, screenPoint); 

       canvas.drawBitmap(BitmapFactory.decodeResource(getResources(), 
         R.drawable.ic_delete), screenPoint.x, screenPoint.y, null); 
      } 



    @Override 
     public boolean onTouchEvent(MotionEvent event) { 
      if (event.getAction() == 1) { 
       GeoPoint p = mapView.getProjection().fromPixels((int) event.getX(), 
         (int) event.getY()); 
       Toast.makeText(GPSMap_Activity.this, 
         p.getLatitudeE6()/1E6 + " " + p.getLongitudeE6()/1E6, 
         Toast.LENGTH_LONG).show(); 
      } 
      return true; 
     } 



     } 


In Xml: 


<com.google.android.maps.MapView 
     android:id="@+id/mapView" 
     android:layout_width="fill_parent" 
     android:layout_height="250dip" 
     android:layout_alignParentLeft="true" 
     android:apiKey="@string/Google_Api_key" 
     android:clickable="true" > 

    </com.google.android.maps.MapView>