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我对 Android 应用程序开发非常陌生。在我正在制作的这个练习应用程序中，当应用程序启动时，它首先检查是否启用了位置提供程序以及是否启用了该数据。

我已经在 Androidmanifest 中设置了权限 ACCESS_NETWORK_STATE 但应用程序仍然崩溃。

我想就如何解决这个问题征求一些建议。

谢谢！

这是我的代码：

    public class MainActivity extends Activity {

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

       LocationManager locMan = (LocationManager) getSystemService (LOCATION_SERVICE);
       ConnectivityManager conMan = (ConnectivityManager) getSystemService (CONNECTIVITY_SERVICE);
       boolean statCheck = locMan.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
       boolean dataConCheck =  conMan.getActiveNetworkInfo().isConnected();

       if (statCheck == false) {
         Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
         startActivity(intent);
    }

       if (dataConCheck == false) {
         Intent intent = new Intent (Settings.ACTION_WIRELESS_SETTINGS);
         startActivity(intent);
    }

}

    05-11 00:58:52.349: W/dalvikvm(1354): threadid=1: thread exiting with uncaught exception (group=0x40018578)
    05-11 00:58:52.359: E/AndroidRuntime(1354): FATAL EXCEPTION: main
    05-11 00:58:52.359: E/AndroidRuntime(1354): java.lang.RuntimeException: Unable to start activity ComponentInfo{cheapapps.productivity.inviter/cheapapps.productivity.inviter.MainActivity}: java.lang.NullPointerException
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at android.app.ActivityThread.access$1500(ActivityThread.java:117)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at android.os.Handler.dispatchMessage(Handler.java:99)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at android.os.Looper.loop(Looper.java:130)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at android.app.ActivityThread.main(ActivityThread.java:3687)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at java.lang.reflect.Method.invokeNative(Native Method)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at java.lang.reflect.Method.invoke(Method.java:507)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at dalvik.system.NativeStart.main(Native Method)
    05-11 00:58:52.359: E/AndroidRuntime(1354): Caused by: java.lang.NullPointerException
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at cheapapps.productivity.inviter.MainActivity.onCreate(MainActivity.java:25)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
    05-11 00:58:52.359: E/AndroidRuntime(1354):     ... 11 more
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1 回答 1

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添加使用权限 ->ACCESS_COARSE_LOCATION或 ACCESS_FINE_LOCATION，具体取决于您的要求。

参考这个

于 2013-05-10T18:45:35.303 回答