我正在尝试使用根据手机方向旋转的地图来显示地图。我已经重写了谷歌示例的一部分以使用 aSensorEventListner而不是SensorListener.
我的问题是当我尝试使用该findViewByID()方法显示地图时，我的应用程序在启动时崩溃了。如果我MapView(Context, String)用来创建我的视图，它工作正常。我错过了使用 main.xml 布局文件的东西吗？这有什么问题？
提前致谢。
这是我的代码：
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
mRotateView = new RotateView(this);
// Seems ok
mMapView = new MapView(this, "0t6yfD1f6K1wZe99RmpB2KdpQHl23WZSPRtGLEg");
// Does not work: application crash on launch.
//setContentView(R.layout.main);
//mMapView = (MapView) findViewById(R.id.mapview);
mRotateView.addView(mMapView);
setContentView(mRotateView);
mMyLocationOverlay = new MyLocationOverlay(this, mMapView);
mMyLocationOverlay.runOnFirstFix(new Runnable() {
public void run() {
mMapView.getController().animateTo(
mMyLocationOverlay.getMyLocation());
}
});
mMapView.getOverlays().add(mMyLocationOverlay);
mMapView.getController().setZoom(18);
mMapView.setClickable(true);
mMapView.setEnabled(true);
mMapView.setBuiltInZoomControls(true);
}
安卓清单：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.hello" android:versionCode="1"
android:versionName="1.0">
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
<application android:icon="@drawable/icon" android:label="@string/app_name"
android:theme="@android:style/Theme.NoTitleBar">
<uses-library android:name="com.google.android.maps" />
<activity android:name=".HelloGoogleMapsActivity"
android:label="@string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
资源/布局/main.xml：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<com.google.android.maps.MapView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/mapview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:clickable="true"
android:apiKey="0t6yfD1f6K1wZe99RmpB2KdpQHl23WZSPRtGLEg"
/>
</LinearLayout>
06-04 18:07:31.512: INFO/ActivityManager(66): Starting activity: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10200000 cmp=com.example.hello/.HelloGoogleMapsActivity }
06-04 18:07:31.842: INFO/ActivityManager(66): Start proc com.example.hello for activity com.example.hello/.HelloGoogleMapsActivity: pid=207 uid=10025 gids={3003, 1015}
06-04 18:07:33.053: ERROR/ActivityThread(207): Failed to find provider info for com.google.settings
06-04 18:07:33.063: ERROR/ActivityThread(207): Failed to find provider info for com.google.settings
06-04 18:07:33.093: ERROR/ActivityThread(207): Failed to find provider info for com.google.settings
06-04 18:07:33.282: DEBUG/qemud(34): fdhandler_accept_event: accepting on fd 10
06-04 18:07:33.282: DEBUG/qemud(34): created client 0x150b8 listening on fd 15
06-04 18:07:33.282: DEBUG/qemud(34): client_fd_receive: attempting registration for service 'sensors'
06-04 18:07:33.282: DEBUG/qemud(34): client_fd_receive: -> received channel id 8
06-04 18:07:33.292: DEBUG/qemud(34): client_registration: registration succeeded for client 8
06-04 18:07:33.302: DEBUG/qemud(34): fdhandler_event: disconnect on fd 15
06-04 18:07:33.312: DEBUG/SensorManager(207): found sensor: Goldfish 3-axis Accelerometer, handle=0
06-04 18:07:33.725: DEBUG/AndroidRuntime(207): Shutting down VM
06-04 18:07:33.725: WARN/dalvikvm(207): threadid=3: thread exiting with uncaught exception (group=0x4001aa28)
06-04 18:07:33.732: ERROR/AndroidRuntime(207): Uncaught handler: thread main exiting due to uncaught exception
06-04 18:07:33.772: ERROR/AndroidRuntime(207): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.hello/com.example.hello.HelloGoogleMapsActivity}: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2401)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.app.ActivityThread.access$2100(ActivityThread.java:116)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.os.Handler.dispatchMessage(Handler.java:99)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.os.Looper.loop(Looper.java:123)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.app.ActivityThread.main(ActivityThread.java:4203)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at java.lang.reflect.Method.invokeNative(Native Method)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at java.lang.reflect.Method.invoke(Method.java:521)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at dalvik.system.NativeStart.main(Native Method)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): Caused by: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.view.ViewGroup.addViewInner(ViewGroup.java:1856)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.view.ViewGroup.addView(ViewGroup.java:1751)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.view.ViewGroup.addView(ViewGroup.java:1708)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.view.ViewGroup.addView(ViewGroup.java:1688)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at com.example.hello.HelloGoogleMapsActivity.onCreate(HelloGoogleMapsActivity.java:156)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2364)
06-04 18:07:33.772: ERROR/AndroidRuntime(207): ... 11 more
06-04 18:07:33.812: INFO/Process(66): Sending signal. PID: 207 SIG: 3
06-04 18:07:33.822: INFO/dalvikvm(207): threadid=7: reacting to signal 3
06-04 18:07:33.962: INFO/dalvikvm(207): Wrote stack trace to '/data/anr/traces.txt'
06-04 18:07:34.412: INFO/ARMAssembler(66): generated scanline__00000077:03515104_00000000_00000000 [ 27 ipp] (41 ins) at [0x2aa9e8:0x2aaa8c] in 1786681 ns
06-04 18:07:34.442: INFO/ARMAssembler(66): generated scanline__00000077:03515104_00001001_00000000 [ 64 ipp] (84 ins) at [0x2ac4f8:0x2ac648] in 2802312 ns
06-04 18:07:41.580: WARN/ActivityManager(66): Launch timeout has expired, giving up wake lock!
06-04 18:07:42.550: WARN/ActivityManager(66): Activity idle timeout for HistoryRecord{4379c288 com.example.hello/.HelloGoogleMapsActivity}
我认为问题在于我调用了 setContentView() 2 次：
setContentView(R.layout.main);
mMapView = (MapView) findViewById(R.id.mapview);
mRotateView.addView(mMapView);
setContentView(mRotateView);
我试图评论第一个 setContentView(R.layout.main); 但应用程序在启动时仍然崩溃。它导致 NullPointerException ：
06-05 10:30:10.272: WARN/dalvikvm(211): threadid=3: thread exiting with uncaught exception (group=0x4001aa28)
06-05 10:30:10.282: ERROR/AndroidRuntime(211): Uncaught handler: thread main exiting due to uncaught exception
06-05 10:30:10.312: ERROR/AndroidRuntime(211): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.hello/com.example.hello.HelloGoogleMapsActivity}: java.lang.NullPointerException
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2401)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.app.ActivityThread.access$2100(ActivityThread.java:116)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.os.Handler.dispatchMessage(Handler.java:99)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.os.Looper.loop(Looper.java:123)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.app.ActivityThread.main(ActivityThread.java:4203)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at java.lang.reflect.Method.invokeNative(Native Method)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at java.lang.reflect.Method.invoke(Method.java:521)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at dalvik.system.NativeStart.main(Native Method)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): Caused by: java.lang.NullPointerException
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.view.ViewGroup.addView(ViewGroup.java:1701)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.view.ViewGroup.addView(ViewGroup.java:1688)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at com.example.hello.HelloGoogleMapsActivity.onCreate(HelloGoogleMapsActivity.java:156)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2364)
06-05 10:30:10.312: ERROR/AndroidRuntime(211): ... 11 more
现在我知道问题出在哪里了；但我不知道如何使用 main.xml 文件创建我的 MapView。
我正在使用 new MapView() 代替；它确实有效，但这是实现它的好方法吗？