"WebMap"활동을 시작할 때 NullPointerException이 발생했습니다.

Question

웹 맵 활동 구현과 관련하여 Google에서 제공 한 코드를 따라했지만 모든 코드를 이해했지만 활동을 시작할 때 Java Null 포인터 예외가 있다고 생각합니다. t는 위도와 경도를 보여 주며, 나는 그 문제를 해결하는 방법을 모른다. 다음은 코드입니다.

public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 
     getLocation(); 
     setupWebView(); 
     this.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT); 
     } 


     private void setupWebView(){ 
//  mostRecentLocation.setLatitude(36.848427); 
//  mostRecentLocation.setLongitude(10.26829); 
      final String centerURL = "javascript:centerAt(" + 
      mostRecentLocation.getLatitude() + "," + 
      mostRecentLocation.getLongitude()+ ")"; 
      webView = (WebView) findViewById(R.id.webview); 
      webView.getSettings().setJavaScriptEnabled(true); 
      //Wait for the page to load then send the location information 
      webView.setWebViewClient(new WebViewClient()); 
      webView.loadUrl(MAP_URL); 
      /** Allows JavaScript calls to access application resources **/ 
      webView.addJavascriptInterface(new JavaScriptInterface(), "android"); 
     } 

logcat은 setupWebView() 함수에 문제가 있음을 나타냅니다. 도움 주셔서 감사합니다. 로그 캣 :

02-29 13:06:42.284: E/AndroidRuntime(642): FATAL EXCEPTION: main 
02-29 13:06:42.284: E/AndroidRuntime(642): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.android.powerful/com.android.powerful.WebMapActivity}: java.lang.NullPointerException 
02-29 13:06:42.284: E/AndroidRuntime(642): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647) 
02-29 13:06:42.284: E/AndroidRuntime(642): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663) 
02-29 13:06:42.284: E/AndroidRuntime(642): at android.app.ActivityThread.access$1500(ActivityThread.java:117) 
02-29 13:06:42.284: E/AndroidRuntime(642): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931) 
02-29 13:06:42.284: E/AndroidRuntime(642): at android.os.Handler.dispatchMessage(Handler.java:99) 
02-29 13:06:42.284: E/AndroidRuntime(642): at android.os.Looper.loop(Looper.java:130) 
02-29 13:06:42.284: E/AndroidRuntime(642): at android.app.ActivityThread.main(ActivityThread.java:3683) 
02-29 13:06:42.284: E/AndroidRuntime(642): at java.lang.reflect.Method.invokeNative(Native Method) 
02-29 13:06:42.284: E/AndroidRuntime(642): at java.lang.reflect.Method.invoke(Method.java:507) 
02-29 13:06:42.284: E/AndroidRuntime(642): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 
02-29 13:06:42.284: E/AndroidRuntime(642): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 
02-29 13:06:42.284: E/AndroidRuntime(642): at dalvik.system.NativeStart.main(Native Method) 
02-29 13:06:42.284: E/AndroidRuntime(642): Caused by: java.lang.NullPointerException 
02-29 13:06:42.284: E/AndroidRuntime(642): at com.android.powerful.WebMapActivity.setupWebView(WebMapActivity.java:30) 
02-29 13:06:42.284: E/AndroidRuntime(642): at com.android.powerful.WebMapActivity.onCreate(WebMapActivity.java:24) 
02-29 13:06:42.284: E/AndroidRuntime(642): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) 
02-29 13:06:42.284: E/AndroidRuntime(642): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611) 

Answer 1

mostRecentLocation 아마 null입니다. 그런 이유로 getLatitude에 액세스하려고하면 예외가 발생합니다. 게시 한 코드에 mostRecentLocation 초기화 코드가 표시되지 않습니다.