Android：谷歌地图显示多个位置

Question

我正在使用http://developer.android.com/resources/tutorials/views/hello-mapview.html#top 使用标记在地图中显示多个位置的教程。但它不显示位置。它只显示地图。这是我的代码。

package com.Map2;

import java.util.List;

import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapView;
import com.google.android.maps.Overlay;
import com.google.android.maps.OverlayItem;
import android.graphics.drawable.Drawable;
import android.os.Bundle;

public class Main extends MapActivity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        MapView mapView = (MapView) findViewById(R.id.theMap);
        mapView.setBuiltInZoomControls(true);


        List<Overlay> mapOverlays = mapView.getOverlays();
        Drawable drawable = this.getResources().getDrawable(R.drawable.marker);
        HelloItemizedOverlay itemizedoverlay = new HelloItemizedOverlay(drawable, this);


        GeoPoint point = new GeoPoint(19240000,-99120000);
        OverlayItem overlayitem = new OverlayItem(point, "Hola, Mundo!", "I'm in Mexico City!");

        itemizedoverlay.addOverlay(overlayitem);
        mapOverlays.add(itemizedoverlay);


        GeoPoint point2 = new GeoPoint(35410000, 139460000);
        OverlayItem overlayitem2 = new OverlayItem(point2, "Sekai, konichiwa!", "I'm in Japan!");
        itemizedoverlay.addOverlay(overlayitem2);
        mapOverlays.add(itemizedoverlay);

    }


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

我的另一门课是……

package com.Map2;

import java.util.ArrayList;

import android.app.AlertDialog;
import android.content.Context;
import android.graphics.drawable.Drawable;

import com.google.android.maps.ItemizedOverlay;
import com.google.android.maps.OverlayItem;

public class HelloItemizedOverlay extends ItemizedOverlay {

    private ArrayList<OverlayItem> mOverlays = new ArrayList<OverlayItem>();
    Context mContext;


    public HelloItemizedOverlay(Drawable defaultMarker) {
          super(boundCenterBottom(defaultMarker));
        }

    public void addOverlay(OverlayItem overlay) {
        mOverlays.add(overlay);
        populate();
    }

    @Override
    protected OverlayItem createItem(int i) {
      return mOverlays.get(i);
    }

    @Override
    public int size() {
      return mOverlays.size();
    }

    public HelloItemizedOverlay(Drawable defaultMarker, Context context) {
          super(defaultMarker);
          mContext = context;
        }

    @Override
    protected boolean onTap(int index) {
      OverlayItem item = mOverlays.get(index);
      AlertDialog.Builder dialog = new AlertDialog.Builder(mContext);
      dialog.setTitle(item.getTitle());
      dialog.setMessage(item.getSnippet());
      dialog.show();
      return true;
    }

}

请尽快帮助我。谢谢。

Answer 1

使用这个HelloItemizedOverlay类代码

import java.util.ArrayList;

import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.graphics.drawable.Drawable;

import com.google.android.maps.ItemizedOverlay;
import com.google.android.maps.OverlayItem;

public class CustomItemizedOverlay extends ItemizedOverlay {

    private ArrayList<OverlayItem> mOverlays = new ArrayList<OverlayItem>();
    private Context mContext;
    public CustomItemizedOverlay(Drawable defaultMarker, Context context) {
        super(boundCenterBottom(defaultMarker));
        mContext = context;
    }

    public void addOverlay(OverlayItem overlay) {
        mOverlays.add(overlay);
        populate();
    }

    @Override
    protected OverlayItem createItem(int i) {
        return mOverlays.get(i);
    }

    @Override
    public int size() {
        return mOverlays.size();
    }

    @Override
    protected boolean onTap(int index) {
      OverlayItem item = mOverlays.get(index);
      AlertDialog.Builder dialog = new AlertDialog.Builder(mContext);
      dialog.setTitle(item.getTitle());
      dialog.setMessage(item.getSnippet());
      dialog.show();
      return true;
    }
}