API 级别 8 到 17 的 Google Maps API V2 android 应用程序答案

【问题标题】：Google Maps API V2 android app on API level 8 up to 17API 级别 8 到 17 的 Google Maps API V2 android 应用程序
【发布时间】：2013-02-16 23:52:42
【问题描述】：

我正在使用 Google 地图 API V2，它运行良好。我有一个 2.2.2 的 android 设备，我用它来调试我的应用程序。

现在我刚拿到 Galaxy Note 2，当我尝试在该设备上调试时，应用程序立即崩溃“项目已停止工作”。

所以我只是做了一个小例子来测试。再次，它在 2.2.2 上运行良好，但在 4.1.1 上运行不佳。

这是我用于小示例练习的代码

任何建议将不胜感激

我的布局

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/tv_location"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <fragment xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/map"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@id/tv_location"
        class="com.google.android.gms.maps.SupportMapFragment" />
</RelativeLayout>

我的清单

    <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.ss"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />

    <permission 
        android:name="com.example.ss.permission.MAPS_RECEIVE"
        android:protectionLevel="signature"/>


    <uses-permission android:name="com.example.ss.permission.MAPS_RECEIVE"/>
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

    <uses-feature
        android:glEsVersion="0x00020000"
        android:required="true"/>


    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >

        <uses-library android:name="com.google.android.maps" />
        <activity
            android:name="com.example.ss.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <meta-data
            android:name="com.google.android.maps.v2.API_KEY"
             android:value="my key"/>
    </application>

</manifest>

还有我的测试代码

public class MainActivity extends FragmentActivity implements LocationListener{

private GoogleMap googleMap;
private LatLng source;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

     int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(getBaseContext());

        if(status!=ConnectionResult.SUCCESS){
            int requestCode = 10;
            Dialog dialog = GooglePlayServicesUtil.getErrorDialog(status, this, requestCode);
            dialog.show();
        }else{
            SupportMapFragment fm = (SupportMapFragment)getSupportFragmentManager().findFragmentById(R.id.map);

            googleMap = fm.getMap();

            googleMap.setMyLocationEnabled(false);

            LocationManager locManager = (LocationManager) getSystemService(LOCATION_SERVICE);

            Criteria criteria = new Criteria();

            String provider = locManager.getBestProvider(criteria, true);

            Location loc = locManager.getLastKnownLocation(provider);


            if(loc!=null){
                onLocationChanged(loc);
            }
            source = new LatLng(loc.getLatitude(), loc.getLongitude());
            //makeUrl = new MakeUrl(source, destination);
            //String url = makeUrl.makeLocationUrl();
            googleMap.moveCamera(CameraUpdateFactory.newLatLng(source));
            googleMap.animateCamera(CameraUpdateFactory.zoomTo(15));
        }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.activity_main, menu);
    return true;
}

@Override
public void onLocationChanged(Location arg0) {
    // TODO Auto-generated method stub

}

@Override
public void onProviderDisabled(String arg0) {
    // TODO Auto-generated method stub

}

@Override
public void onProviderEnabled(String arg0) {
    // TODO Auto-generated method stub

}

@Override
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
    // TODO Auto-generated method stub

}

}

我在 NOTE 2 上得到的堆栈跟踪

    02-17 13:03:23.135: D/dalvikvm(9527): Late-enabling CheckJNI
02-17 13:03:23.170: E/Trace(9527): error opening trace file: No such file or directory (2)
02-17 13:03:23.345: D/dalvikvm(9527): GC_CONCURRENT freed 179K, 6% free 12453K/13191K, paused 2ms+1ms, total 33ms
02-17 13:03:23.345: D/dalvikvm(9527): WAIT_FOR_CONCURRENT_GC blocked 26ms
02-17 13:03:23.575: D/dalvikvm(9527): GC_CONCURRENT freed 279K, 7% free 12634K/13511K, paused 12ms+1ms, total 24ms
02-17 13:03:23.665: D/dalvikvm(9527): GC_CONCURRENT freed 276K, 7% free 12862K/13703K, paused 2ms+12ms, total 29ms
02-17 13:03:23.705: D/AbsListView(9527): Get MotionRecognitionManager
02-17 13:03:23.740: D/dalvikvm(9527): GC_CONCURRENT freed 194K, 6% free 13206K/13959K, paused 2ms+2ms, total 20ms
02-17 13:03:23.740: D/dalvikvm(9527): WAIT_FOR_CONCURRENT_GC blocked 9ms
02-17 13:03:23.745: D/dalvikvm(9527): WAIT_FOR_CONCURRENT_GC blocked 9ms
02-17 13:03:23.760: D/AndroidRuntime(9527): Shutting down VM
02-17 13:03:23.760: W/dalvikvm(9527): threadid=1: thread exiting with uncaught exception (group=0x41c802a0)
02-17 13:03:23.760: E/AndroidRuntime(9527): FATAL EXCEPTION: main
02-17 13:03:23.760: E/AndroidRuntime(9527): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.mm/com.example.mm.MainActivity}: java.lang.NullPointerException
02-17 13:03:23.760: E/AndroidRuntime(9527):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2100)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2125)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at android.app.ActivityThread.access$600(ActivityThread.java:140)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1227)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at android.os.Handler.dispatchMessage(Handler.java:99)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at android.os.Looper.loop(Looper.java:137)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at android.app.ActivityThread.main(ActivityThread.java:4898)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at java.lang.reflect.Method.invokeNative(Native Method)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at java.lang.reflect.Method.invoke(Method.java:511)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1008)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:775)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at dalvik.system.NativeStart.main(Native Method)
02-17 13:03:23.760: E/AndroidRuntime(9527): Caused by: java.lang.NullPointerException
02-17 13:03:23.760: E/AndroidRuntime(9527):     at com.example.mm.MainActivity.onCreate(MainActivity.java:82)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at android.app.Activity.performCreate(Activity.java:5191)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
02-17 13:03:23.760: E/AndroidRuntime(9527):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064)
02-17 13:03:23.760: E/AndroidRuntime(9527):     ... 11 more
02-17 13:03:23.955: D/dalvikvm(9527): GC_CONCURRENT freed 233K, 6% free 13394K/14215K, paused 14ms+1ms, total 44ms

【问题讨论】：

请同时发布来自 logcat 的堆栈跟踪或错误消息。
@mdiener Stacktrace 已添加
由于您的源代码中没有可见的行号，即 MainActivity 中的第 82 行？
@mdiener 对不起，那是在源头 = new LatLng(loc.getLatitude(), loc.getLongitude());

标签： google-maps-android-api-2 supportmapfragment mapfragment

【解决方案1】：

似乎没有该位置提供者的最后一个已知位置。如果该位置提供者从未进行过位置修复，则可能会发生这种情况。只需尝试更好地解决 loc == null 的情况。

【讨论】：