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POWeird null pointer exception with DbHelper class context, code within
 

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  1. POWeird null pointer exception with DbHelper class context, code within
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    <p>I am getting a null pointer on this code... So lost.</p> <p>I have a Database helper class called DbAdapter.</p> <pre><code>public class DbAdapter { private final Context mCtx; public DbAdapter(Context ctx) { mCtx = ctx; //set context } /// This function adds all the student INFO to the DB public long addStudentInfoToDb(String stuID,String stuFName, String stuLName) { ContentValues student_info = new ContentValues(); student_info.put(STU_ID, stuID); student_info.put(STU_FNAME, stuFName); student_info.put(STU_LNAME, stuLName); return mDb.insert("Student", null, student_info); } </code></pre> <p>And I am using this info in another class/activity called:LoginScreenActivity</p> <p>I declare the DbAdapter class like this... dbHelper = new DbAdapter(LoginScreenActivity.this);</p> <pre><code> public void loginScreenFill() { final EditText student_id = (EditText) findViewById(R.id.student_id_edit); final EditText student_fname = (EditText) findViewById(R.id.fname_edit); final EditText student_lname = (EditText) findViewById(R.id.lname_edit); final EditText course_code = (EditText) findViewById(R.id.classcode_edit); Button login_button = (Button) findViewById(R.id.login_button); login_button.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { // TODO Auto-generated method stub String id = String.valueOf((student_id.getText())); String first_name = String.valueOf(student_fname.getText()); String last_name = String.valueOf(student_lname.getText()); String class_code = String.valueOf(course_code.getText()); dbHelper.addStudentInfoToDb(id, first_name, last_name); addStudentInfo(id,first_name,last_name); } </code></pre> <p>And I am getting this... 07-27 19:26:02.211: E/AndroidRuntime(1924): java.lang.NullPointerException 07-27 19:09:22.615: E/AndroidRuntime(1113): at com.test.quizapp.DbAdapter.addStudentInfoToDb(DbAdapter.java:121)</p> <pre><code>07-27 19:26:02.211: E/AndroidRuntime(1924): FATAL EXCEPTION: main 07-27 19:26:02.211: E/AndroidRuntime(1924): java.lang.NullPointerException 07-27 19:26:02.211: E/AndroidRuntime(1924): at com.test.quizapp.DbAdapter.addStudentInfoToDb(DbAdapter.java:121) 07-27 19:26:02.211: E/AndroidRuntime(1924): at com.test.quizapp.LoginScreenActivity$1.onClick(LoginScreenActivity.java:54) 07-27 19:26:02.211: E/AndroidRuntime(1924): at android.view.View.performClick(View.java:4211) 07-27 19:26:02.211: E/AndroidRuntime(1924): at android.view.View$PerformClick.run(View.java:17362) 07-27 19:26:02.211: E/AndroidRuntime(1924): at android.os.Handler.handleCallback(Handler.java:725) 07-27 19:26:02.211: E/AndroidRuntime(1924): at android.os.Handler.dispatchMessage(Handler.java:92) 07-27 19:26:02.211: E/AndroidRuntime(1924): at android.os.Looper.loop(Looper.java:137) 07-27 19:26:02.211: E/AndroidRuntime(1924): at android.app.ActivityThread.main(ActivityThread.java:5227) 07-27 19:26:02.211: E/AndroidRuntime(1924): at java.lang.reflect.Method.invokeNative(Native Method) 07-27 19:26:02.211: E/AndroidRuntime(1924): at java.lang.reflect.Method.invoke(Method.java:511) 07-27 19:26:02.211: E/AndroidRuntime(1924): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:795) 07-27 19:26:02.211: E/AndroidRuntime(1924): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:562) 07-27 19:26:02.211: E/AndroidRuntime(1924): at dalvik.system.NativeStart.main(Native Method) </code></pre>
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    1. PTQuestion
    1. USwilxjcherokee
    1. USwilxjcherokee
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    1. PO
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      1. PTAnswer
    1. VO
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      1. POWeird null pointer exception with DbHelper class context, code within
      1. This table or related slice is empty.
      1. VTUpMod
    1. COOn which line do you get NPE ? Can you post complete LogCat ?
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      1. POWeird null pointer exception with DbHelper class context, code within
      1. USShobhit Puri
    2. COProblem is in this line: `return mDb.insert("Student", null, student_info);`. `mDb` could be null/uninitialized.
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      1. POWeird null pointer exception with DbHelper class context, code within
      1. USVikram
    3. COI am not sure how it could be null since I am grabbing it from the text box within the method! I think it has to do with my DB context but I can't figure it out :(
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      1. POWeird null pointer exception with DbHelper class context, code within
      1. USwilxjcherokee
 

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