將數據從活動傳遞到片段時出現空指針異常

我試圖在FragmentActivity和Fragment之間傳遞數據。將數據從活動傳遞到片段時出現空指針異常

在片段活性的OnCreate方法，其中，pid值從另一個活動發送到該片段的活性，我該PID值傳遞給一個片段：

Intent i = getIntent(); 

     Bundle extras = i.getExtras(); 
     pid = extras.getString("TAG_PATIENT_ID"); 
     System.out.println("Pid in prescact"+pid); 
     // Bundle bundle = new Bundle(); 

     /* bundle.putString("TAG_PATIENT_ID",pid); 
     Intent m = new Intent(PrescAct.this,DocPresc1.class); 
      m.putExtras(bundle);*/ 
    //Passing pid value to the list fragment   
     Bundle b = new Bundle(); 
     b.putString("TAG_PATIENT_ID",pid); 
     Fragment f = new DocPresc1(); 
     f.setArguments(b);

在檢索從該fragmentActivity值插入到一個片段我得到空指針異常。在片段類的OnCreateView方法：

Bundle b = getArguments(); 
       pid = b.getString("TAG_PATIENT_ID"); 
       System.out.println("Docpresc"+pid);

這裏是棧跟蹤：

06-20 12:44:34.767: E/AndroidRuntime(9394): FATAL EXCEPTION: main 
06-20 12:44:34.767: E/AndroidRuntime(9394): java.lang.NullPointerException 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at com.example.actionbar.DocPresc1.onCreateView(DocPresc1.java:104) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.support.v4.app.Fragment.performCreateView(Fragment.java:1460) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:461) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:141) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.support.v4.view.ViewPager.populate(ViewPager.java:1011) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.support.v4.view.ViewPager.populate(ViewPager.java:880) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1374) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.View.measure(View.java:15479) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:617) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:399) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.View.measure(View.java:15479) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4828) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.View.measure(View.java:15479) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.widget.LinearLayout.measureVertical(LinearLayout.java:833) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.widget.LinearLayout.onMeasure(LinearLayout.java:574) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.View.measure(View.java:15479) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4828) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2359) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.View.measure(View.java:15479) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1968) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1214) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1387) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1107) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4464) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.Choreographer$CallbackRecord.run(Choreographer.java:725) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.Choreographer.doCallbacks(Choreographer.java:555) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.Choreographer.doFrame(Choreographer.java:525) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:711) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.os.Handler.handleCallback(Handler.java:615) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.os.Handler.dispatchMessage(Handler.java:92) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.os.Looper.loop(Looper.java:137) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at android.app.ActivityThread.main(ActivityThread.java:4895) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at java.lang.reflect.Method.invokeNative(Native Method) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at java.lang.reflect.Method.invoke(Method.java:511) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:994) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:761) 
06-20 12:44:34.767: E/AndroidRuntime(9394):  at dalvik.system.NativeStart.main(Native Method)

來源

2013-06-20 Manav Singhal

參閱此http：//計算器。 com/questions/12873635 /傳遞參數從android-fragmentactivity到片段 – Riser

我推薦這個stackoverflow.com/questions/12739909/send-data-from-activity-to-fragment-in-android –

請提出爲什麼我在線上得到這個空指針異常： pid = b.getString（「TAG_PATIENT_ID」）; –

-1

至是通過使用意圖從一個活動的數據發送到另一個活動的最簡單方法，如下所示：

Intent intent = new Intent(Activity.this, FragmentActivity.class); 
intent.putExtra("Key", value); 
startActivity(intent);

現在在接收器FragmentActivity中獲取密鑰的值，如下所示：

Declare variable: 
public String key;

獲取從意圖值到onCreate方法變量：

Intent intent = getIntent(); 
key = intent.getStringExtra("Key");

現在使用此代碼在您的片段使用此鍵值：

String key = ((FragmentActivity)this.getActivity()).key;

來源

2013-06-20 07:30:30

這不起作用。 ... –

plz解釋瞭如何將線路工作String key =（（FragmentActivity）this.getActivity（））。 –

問題在於將數據從活動發送到片段，而不是發送到其他活動。 – devconsole

將數據從活動傳遞到片段時出現空指針異常

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