我做的發現這裏的MapView教程:https://developers.google.com/maps/documentation/android/v1/hello-mapview谷歌地圖API的Android V1的MapView教程崩潰
的問題是,它總是崩潰。下面的代碼:
package com.example.googlemapstest;
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.os.Bundle;
import android.app.Activity;
import android.graphics.drawable.Drawable;
import android.view.Menu;
public class MainActivity extends MapActivity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
MapView mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
List<Overlay> mapOverlays = mapView.getOverlays();
Drawable drawable = this.getResources().getDrawable(R.drawable.androidmarker);
HelloItemizedOverlay itemizedoverlay = new HelloItemizedOverlay(drawable, this);
GeoPoint point = new GeoPoint(19240000,-99120000);
OverlayItem overlayitem = new OverlayItem(point, "Hola, Mundo!", "I'm in Mexico City!");
drawable.setBounds(0,0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
overlayitem.setMarker(drawable);
itemizedoverlay.addOverlay(overlayitem, drawable);
mapOverlays.add(itemizedoverlay);
}
@Override
protected boolean isRouteDisplayed() {
return false;
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
而且HelloItemizedOverlay類:
package com.example.googlemapstest;
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;
Context mContext;
public HelloItemizedOverlay(Drawable defaultMarker) {
super(boundCenterBottom(defaultMarker));
mOverlays = new ArrayList<OverlayItem>();
populate();
}
public void addOverlay(OverlayItem overlay, Drawable drawable) {
overlay.setMarker(drawable);
mOverlays.add(overlay);
populate();
}
@Override
public int size() {
return mOverlays.size();
}
public HelloItemizedOverlay(Drawable defaultMarker, Context context) {
super(boundCenterBottom(defaultMarker));
mContext = context;
mOverlays = new ArrayList<OverlayItem>();
populate();
}
@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;
}
@Override
protected OverlayItem createItem(int arg0) {
// TODO Auto-generated method stub
return null;
}
}
我不斷收到唯一的例外是
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.googlemapstest/com.example.googlemapstest.MainActivity} : java.lang.NullPointerException
崩潰發生在填入()行itemizedoverlay.addOverlay( overlayitem,drawable); 現在,最初我發現我添加的OverlayItem的mMarker變量爲null,並添加了兩行來手動設置它。但是,該方案仍然不斷崩潰!
然後我發現這個問題:Problem with crash with ItemizedOverlay這似乎是處理同樣的錯誤。
我按照最佳答案的建議做了,但仍然沒有運氣。
我相信我已經很好地梳理了這一點,並且無法想象空錯誤來自哪裏。任何幫助深表感謝。
您使用地圖v1而不是v2的任何特定原因?如果您使用的是不推薦使用的庫,您將會獲得更多幫助。 – ianhanniballake 2013-02-26 00:03:56
我開始維護api v1應用程序,並且正在做本教程以掌握基本概念。 – user1401321 2013-03-01 12:57:52