我的应用程序显示地图,我希望用户无法在特定区域滑动。因此,我尝试添加边界,但这会导致应用程序崩溃。以下是工作代码:
public class MapViewer extends Activity implements OnInfoWindowClickListener {
private LatLng defaultLatLng = new LatLng(42.564241, 12.22759);
private GoogleMap map;
private int zoomLevel = 5;
private Database db = new Database(this);
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mapviewer);
try {
map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();
if (map != null) {
map.setMyLocationEnabled(true);
map.setMapType(GoogleMap.MAP_TYPE_NORMAL);
map.getUiSettings().setRotateGesturesEnabled(false);
map.moveCamera(CameraUpdateFactory.newLatLngZoom(defaultLatLng, zoomLevel));
this.addMerchantMarkers(new MarkerOptions());
map.setOnInfoWindowClickListener(this);
}
} catch (NullPointerException e) {
e.printStackTrace();
}
}
@Override
public void onPause() {
if (map != null) {
map.setMyLocationEnabled(false);
map.setTrafficEnabled(false);
}
super.onPause();
}
public void addMerchantMarkers(MarkerOptions mo) {
SQLiteDatabase dbRead = db.getReadableDatabase();
String[] columns = {"title", "addr", "lat", "lon"};
Cursor result = dbRead.query("merchants", columns, null, null, null, null, null);
while(result.moveToNext()) {
String merchant = result.getString(0);
String address = result.getString(1);
float lat = result.getFloat(2);
float lon = result.getFloat(3);
LatLng pos = new LatLng(lat, lon);
map.addMarker(mo.position(pos)
.title(merchant)
.snippet(address)
.icon(BitmapDescriptorFactory.fromResource(R.drawable.marker_50)));;
}
}
}
这是我在onCreate方法中添加的代码,导致了崩溃:
LatLngBounds.Builder builder = new LatLngBounds.Builder();
builder.include(new LatLng(47.09194444, 18.52166666));
builder.include(new LatLng(36.448311, 6.62555555));
LatLngBounds bounds = builder.build();
CameraUpdate cu = CameraUpdateFactory.newLatLngBounds(bounds, 30);
map.animateCamera(cu);
以下是 LogCat:
08-10 20:59:41.689: E/AndroidRuntime(6304): FATAL EXCEPTION: main
08-10 20:59:41.689: E/AndroidRuntime(6304): Process: com.example.myapp, PID: 6304
08-10 20:59:41.689: E/AndroidRuntime(6304): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.myapp/com.example.myapp.MapViewer}: java.lang.IllegalStateException: Error using newLatLngBounds(LatLngBounds, int): Map size can't be 0. Most likely, layout has not yet occured for the map view. Either wait until layout has occurred or use newLatLngBounds(LatLngBounds, int, int, int) which allows you to specify the map's dimensions.
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2215)
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2264)
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.app.ActivityThread.access$800(ActivityThread.java:144)
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1205)
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.os.Handler.dispatchMessage(Handler.java:102)
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.os.Looper.loop(Looper.java:136)
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.app.ActivityThread.main(ActivityThread.java:5139)
08-10 20:59:41.689: E/AndroidRuntime(6304): at java.lang.reflect.Method.invokeNative(Native Method)
08-10 20:59:41.689: E/AndroidRuntime(6304): at java.lang.reflect.Method.invoke(Method.java:515)
08-10 20:59:41.689: E/AndroidRuntime(6304): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:796)
08-10 20:59:41.689: E/AndroidRuntime(6304): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:612)
08-10 20:59:41.689: E/AndroidRuntime(6304): at dalvik.system.NativeStart.main(Native Method)
08-10 20:59:41.689: E/AndroidRuntime(6304): Caused by: java.lang.IllegalStateException: Error using newLatLngBounds(LatLngBounds, int): Map size can't be 0. Most likely, layout has not yet occured for the map view. Either wait until layout has occurred or use newLatLngBounds(LatLngBounds, int, int, int) which allows you to specify the map's dimensions.
08-10 20:59:41.689: E/AndroidRuntime(6304): at mut.b(Unknown Source)
08-10 20:59:41.689: E/AndroidRuntime(6304): at oxp.a(Unknown Source)
08-10 20:59:41.689: E/AndroidRuntime(6304): at oxi.a(Unknown Source)
08-10 20:59:41.689: E/AndroidRuntime(6304): at oyf.b(Unknown Source)
08-10 20:59:41.689: E/AndroidRuntime(6304): at grl.onTransact(SourceFile:92)
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.os.Binder.transact(Binder.java:361)
08-10 20:59:41.689: E/AndroidRuntime(6304): at com.google.android.gms.maps.internal.IGoogleMapDelegate$a$a.animateCamera(Unknown Source)
08-10 20:59:41.689: E/AndroidRuntime(6304): at com.google.android.gms.maps.GoogleMap.animateCamera(Unknown Source)
08-10 20:59:41.689: E/AndroidRuntime(6304): at com.example.myapp.MapViewer.onCreate(MapViewer.java:59)
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.app.Activity.performCreate(Activity.java:5231)
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
08-10 20:59:41.689: E/AndroidRuntime(6304): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2169)
08-10 20:59:41.689: E/AndroidRuntime(6304): ... 11 more
MapViewer.java
的第 59 行是什么? - Raghunandan