在我的手機(jī)上構(gòu)建谷歌地圖活動(dòng)時(shí)遇到問題。我創(chuàng)建的程序如下：package com.example.calvin.navigation2;import android.app.Activity;import android.content.Context;import android.support.v4.app.FragmentActivity;import com.google.android.gms.maps.CameraUpdateFactory;import com.google.android.gms.maps.GoogleMap;import com.google.android.gms.maps.OnMapReadyCallback;import com.google.android.gms.maps.SupportMapFragment;import com.google.android.gms.maps.model.LatLng;import com.google.android.gms.maps.model.MarkerOptions;public class MapActivity extends FragmentActivity implements OnMapReadyCallback{    private GoogleMap mMap;    private final Context con;    public MapActivity(Context context) {        this.con = context;        SupportMapFragment mapFragment = (SupportMapFragment) ((FragmentActivity)con).getSupportFragmentManager()                .findFragmentById(R.id.mapView);        mapFragment.getMapAsync(this);    }    @Override    public void onMapReady(GoogleMap googleMap) {        mMap = googleMap;        // Add a marker in Sydney, Australia, and move the camera.        LatLng sydney = new LatLng(-34, 151);        mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));        mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));    }}然后我調(diào)用這個(gè)類中的上一個(gè)類：package com.example.calvin.navigation2;import android.support.v7.app.ActionBar;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.Window;public class Page2Activity extends AppCompatActivity {    LocationTracker tracker;    MapActivity myMap;    @Override    protected void onCreate(Bundle savedInstanceState) {        this.requestWindowFeature(Window.FEATURE_NO_TITLE);        super.onCreate(savedInstanceState);        ActionBar actionBar = getSupportActionBar();        actionBar.hide();        setContentView(R.layout.activity_page2);        myMap = new MapActivity(Page2Activity.this);    }}在編譯它構(gòu)建的程序時(shí)，但是當(dāng)從我的手機(jī)上的應(yīng)用程序調(diào)用時(shí)，它總是會(huì)終止。