NullPointerException with string array in Spinner

Question

The first application, and so actually new on android (played about a year ago, but nothing came of it), decent when programming. Wanting to make sure that the application is displayed on the phone, there is no atm functionality. It compiles perfectly, there are no problems. Click it on your phone and "Sorry, Splitr has stopped."

Edit - added in MainActivity.java, editing has * before and after (not in the actual code), but now the flags

adapter.setDropDownViewResource(android.R.layout.activity_main); // Apply the adapter to the spinner spinnerSplit.setAdapter(adapter); 

says the expected error id is: (18, 36)

setDropDownViewResource, activity_main and setAdapter all in red

Android Studio
Moto G - CM11 4.4.4

Here is the code, let me know if I missed something.

MainActivity.java

 package com.hydr0dr4gon.splitrv2; import android.app.Activity; import android.os.Bundle; import android.view.Menu; import android.view.MenuItem; *import android.widget.ArrayAdapter; import android.widget.Spinner;* public class MainActivity extends Activity { *Spinner spinnerSplit = (Spinner) findViewById(R.id.spinner); // Create an ArrayAdapter using the string array and a default spinner layout ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.arraySplitr, android.R.layout.simple_spinner_item); // Specify the layout to use when the list of choices appears adapter.setDropDownViewResource(android.R.layout.activity_main); // Apply the adapter to the spinner spinnerSplit.setAdapter(adapter);* @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle action bar item clicks here. The action bar will // automatically handle clicks on the Home/Up button, so long // as you specify a parent activity in AndroidManifest.xml. int id = item.getItemId(); if (id == R.id.action_settings) { return true; } return super.onOptionsItemSelected(item); } } 

SplitrDialogFragment.java

 package com.hydr0dr4gon.splitrv2; import android.app.AlertDialog; import android.app.Dialog; import android.app.DialogFragment; import android.content.DialogInterface; import android.os.Bundle; public class SplitrDialogFragment extends DialogFragment { @Override public Dialog onCreateDialog(Bundle savedInstanceState) { // Use the Builder class for convenient dialog construction AlertDialog.Builder builder = new AlertDialog.Builder(getActivity()); builder.setMessage(R.string.dialog_split_pay) .setNegativeButton(R.string.OK, new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int id) { // User cancelled the dialog } }); // Create the AlertDialog object and return it return builder.create(); } } 

strings.xml

 <?xml version="1.0" encoding="utf-8"?> <resources> <string name="app_name">Splitr</string> <string name="hello_world">Hello world!</string> <string name="action_settings">Settings</string> <string name="btnSplit">Split</string> <string name="btnTip">+ Tip</string> <string name="txtSplit">Split By</string> <string name="txtHint">Enter Bill Total</string> <string name="spinnerSplit">No. of People</string> <string name="dialog_split_pay">Each Person Pays</string> <string name="OK">OK</string> <array name="arraySplitr"> <item>2</item> <item>3</item> <item>4</item> <item>5</item> <item>6</item> <item>7</item> <item>8</item> <item>9</item> <item>10</item> </array> 

actvity_main.xml

 RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="fill_parent" android:layout_height="fill_parent" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" android:paddingBottom="@dimen/activity_vertical_margin" tools:context="com.hydr0dr4gon.splitr.MainActivity"> <TableLayout android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_alignParentTop="true" android:layout_alignParentStart="true" android:paddingLeft="40dp" android:paddingTop="80dp" android:paddingRight="40dp" android:paddingBottom="80dp"> <TableRow android:layout_width="fill_parent" android:layout_height="fill_parent"> <EditText android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_span="2" android:inputType="number" android:ems="10" android:id="@+id/editText" android:layout_column="0" android:layout_weight="1.5" android:hint="@string/txtHint" /> </TableRow> <TableRow android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:layout_width="0dp" android:layout_height="match_parent" android:text="@string/txtSplit" android:id="@+id/txtSplit" android:layout_weight="1" android:textSize="32dp" android:textAlignment="center" android:gravity="center" /> <Spinner android:layout_width="0dp" android:layout_height="match_parent" android:id="@+id/spinner" android:layout_weight="1" android:spinnerStyle="@android:style/Widget.Spinner.DropDown" android:textAlignment="center" android:entries="@array/arraySplitr" android:prompt="@string/spinnerSplit"/> </TableRow> <TableRow android:layout_width="fill_parent" android:layout_height="fill_parent"> <Button android:layout_width="0dp" android:layout_height="wrap_content" android:text="@string/btnTip" android:id="@+id/btnTip" android:layout_weight="1" /> <Button android:layout_width="0dp" android:layout_height="wrap_content" android:text="@string/btnSplit" android:id="@+id/btnSplit" android:layout_weight="1" /> </TableRow> </TableLayout> 

Logcat

 > 07-11 21:18:50.899 10290-10290/com.hydr0dr4gon.splitrv2 D/ActivityThread﹕ handleBindApplication:com.hydr0dr4gon.splitrv2 07-11 21:18:50.899 10290-10290/com.hydr0dr4gon.splitrv2 D/ActivityThread﹕ setTargetHeapUtilization:0.75 07-11 21:18:50.899 10290-10290/com.hydr0dr4gon.splitrv2 D/ActivityThread﹕ setTargetHeapMinFree:2097152 07-11 21:18:51.198 10290-10290/com.hydr0dr4gon.splitrv2 D/AndroidRuntime﹕ Shutting down VM 07-11 21:18:51.206 10290-10290/com.hydr0dr4gon.splitrv2 E/AndroidRuntime﹕ FATAL EXCEPTION: main Process: com.hydr0dr4gon.splitrv2, PID: 10290 java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:394) at android.widget.ArrayAdapter.getView(ArrayAdapter.java:362) at android.widget.AbsSpinner.onMeasure(AbsSpinner.java:193) at android.widget.Spinner.onMeasure(Spinner.java:482) at android.view.View.measure(View.java:16521) at android.widget.TableRow.getColumnsWidths(TableRow.java:312) at android.widget.TableLayout.findLargestCells(TableLayout.java:508) at android.widget.TableLayout.measureVertical(TableLayout.java:473) at android.widget.TableLayout.onMeasure(TableLayout.java:439) at android.view.View.measure(View.java:16521) at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:719) at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:455) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at com.android.internal.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:327) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2552) at android.view.View.measure(View.java:16521) at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1912) at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1109) at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1291) at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:996) at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5600) at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761) at android.view.Choreographer.doCallbacks(Choreographer.java:574) at android.view.Choreographer.doFrame(Choreographer.java:544) at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747) at android.os.Handler.handleCallback(Handler.java:733) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:136) at android.app.ActivityThread.main(ActivityThread.java:5137) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:795) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:611) 

Thanks.

Answer 1

 java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:394) at android.widget.ArrayAdapter.getView(ArrayAdapter.java:362) at android.widget.AbsSpinner.onMeasure(AbsSpinner.java:193) at android.widget.Spinner.onMeasure(Spinner.java:482) 

This suggests that the error was measured by Spinner . More precisely, one of the lines that should be displayed inside it is zero.

The most likely cause is a problem with the @array/arraySplitr . Is it a valid string-array resource as defined in the documentation ?

It:

 <array name="arraySplitr"> <item>2</item> ... 

it should be:

 <string-array name="arraySplitr"> <item>2</item> ... 

The array element is for typed arrays . String arrays should use string-array .

Answer 2

There is a NullPointerException in your logcat.

E/AndroidRuntime﹕ FATAL EXCEPTION: main Process: com.hydr0dr4gon.splitrv2, PID: 10290 java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:394)

Something is not initialized. From your code, I don't understand what it will be. Do you have an ArrayAdapter, and if you initialize it and all the objects contained in it? Or is your table just filled with your layout file? I would see how your table fills (based on the logarithm), but I don’t see that the problem will be from the code you posted.