Exception on ListPreferences

Question

This is my first Android app and I've encountered an exception when trying to use the ListPreference. The application loads along with the preferences... but when i touch the ListPreference entry the applications "stops unexpectedly".

Settings.java

public class Settings extends PreferenceActivity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        this.addPreferencesFromResource(R.layout.settings);
    }
}

settings.xml

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen
xmlns:android="http://schemas.android.com/apk/res/android">
    <CheckBoxPreference
        android:key="chk_enabled"
        android:summary="SMS response based on settings"
        android:title="Enable"
    />
    <ListPreference
        android:title="Contacts"
        android:summary="Contacs that will be sent SMSs"
        android:key="list_contacts"
        android:defaultValue="0"
        android:entries="@array/list_entries"
        android:entryValues="@array/list_values" 
    />
</PreferenceScreen>

arrays.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string-array name="list_entries">
        <item>All</item>
        <item>WhiteList</item>
        <item>BlackList</item>
    </string-array>

    <integer-array name="list_values">
        <item>0</item>
        <item>1</item>
        <item>2</item>
    </integer-array>
</resources>

This is the logcat output:

D/AndroidRuntime( 3187): >>>>>>>>>>>>>> AndroidRuntime START <<<<<<<<<<<<<<
D/AndroidRuntime( 3187): CheckJNI is OFF
D/AndroidRuntime( 3187): --- registering native functions ---
I/jdwp    ( 3187): received file descriptor 16 from ADB
/ddm-heap( 3187): Got feature list request
I/ActivityManager(   86): Starting activity: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=tml.UI.main/.MainActivity }
D/AndroidRuntime( 3187): Shutting down VM
D/dalvikvm( 3187): DestroyJavaVM waiting for non-daemon threads to exit
I/ActivityManager(   86): Start proc tml.UI.main for activity tml.UI.main/.MainActivity: pid=3194 uid=10039 gids={1015}
D/dalvikvm( 3187): DestroyJavaVM shutting VM down
D/dalvikvm( 3187): HeapWorker thread shutting down
D/dalvikvm( 3187): HeapWorker thread has shut down
D/jdwp    ( 3187): JDWP shutting down net...
D/jdwp    ( 3187): +++ peer disconnected
I/dalvikvm( 3187): Debugger has detached; object registry had 1 entries
D/dalvikvm( 3187): VM cleaning up
D/dalvikvm( 3187): LinearAlloc 0x0 used 676380 of 4194304 (16%)
I/jdwp    ( 3194): received file descriptor 10 from ADB
D/ddm-heap( 3194): Got feature list request
W/Resources( 3194): Converting to string: TypedValue{t=0x10/d=0x0 a=-1}
I/ActivityManager(   86): Displayed activity tml.UI.main/.MainActivity: 977 ms (total 977 ms)
D/AndroidRuntime( 3194): Shutting down VM
W/dalvikvm( 3194): threadid=3: thread exiting with uncaught exception (group=0x4001da28)
E/AndroidRuntime( 3194): Uncaught handler: thread main exiting due to uncaught exception
E/AndroidRuntime( 3194): java.lang.NullPointerException
E/AndroidRuntime( 3194):    at android.preference.ListPreference.findIndexOfValue(ListPreference.java:169)
E/AndroidRuntime( 3194):    at android.preference.ListPreference.getValueIndex(ListPreference.java:178)
E/AndroidRuntime( 3194):    at android.preference.ListPreference.onPrepareDialogBuilder(ListPreference.java:190)
E/AndroidRuntime( 3194):    at android.preference.DialogPreference.showDialog(DialogPreference.java:291)
E/AndroidRuntime( 3194):    at android.preference.DialogPreference.onClick(DialogPreference.java:262)
E/AndroidRuntime( 3194):    at android.preference.Preference.performClick(Preference.java:811)
E/AndroidRuntime( 3194):    at android.preference.PreferenceScreen.onItemClick(PreferenceScreen.java:190)
E/AndroidRuntime( 3194):    at android.widget.AdapterView.performItemClick(AdapterView.java:284)
E/AndroidRuntime( 3194):    at android.widget.ListView.performItemClick(ListView.java:3246)
E/AndroidRuntime( 3194):    at android.widget.AbsListView$PerformClick.run(AbsListView.java:1635)
E/AndroidRuntime( 3194):    at android.os.Handler.handleCallback(Handler.java:587)
E/AndroidRuntime( 3194):    at android.os.Handler.dispatchMessage(Handler.java:92)
E/AndroidRuntime( 3194):    at android.os.Looper.loop(Looper.java:123)
E/AndroidRuntime( 3194):    at android.app.ActivityThread.main(ActivityThread.java:4203)
E/AndroidRuntime( 3194):    at java.lang.reflect.Method.invokeNative(Native Method)
E/AndroidRuntime( 3194):    at java.lang.reflect.Method.invoke(Method.java:521)
E/AndroidRuntime( 3194):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
E/AndroidRuntime( 3194):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
E/AndroidRuntime( 3194):    at dalvik.system.NativeStart.main(Native Method)
I/Process (   86): Sending signal. PID: 3194 SIG: 3
I/dalvikvm( 3194): threadid=7: reacting to signal 3
I/dalvikvm( 3194): Wrote stack trace to '/data/anr/traces.txt'
I/Process ( 3194): Sending signal. PID: 3194 SIG: 9
I/ActivityManager(   86): Process tml.UI.main (pid 3194) has died.
I/WindowManager(   86): WIN DEATH: Window{4341fd00 tml.UI.main/tml.UI.main.MainActivity paused=false}
W/UsageStats(   86): Unexpected resume of com.android.launcher while already resumed in tml.UI.main
W/InputManagerService(   86): Got RemoteException sending setActive(false) notification to pid 3194 uid 10039

Emmi

Please post the LogCat info. That would help all of us here to help you with the exception. – Siloa

I see logcat is an adb command but I don't know how to use it... could you tell me? – Emmi

Are you using Eclipse ADT? Or the command line tools? – Siloa

I'm using Eclipse ADT. I just pasted the logcat in the question... I started at "AndroidRuntime START" and disregarded all messages preceding the application start. – Emmi

Answer 1

I fixed it... I kept on trying and, at the end, it turns out that I cannot use an integer-array as the entryValues Source. I just changed that integer-array to a string-array and got it working.

If there's a way to use integer-array as the source for entryValues please comment.

Emmi

Has anyone noticed that this works fine in Android 2.3 but you get this error in 4.0 +? – Supple

Seriously... This is outrageous that nobody fixed this since 2009! – Gorge

Answer 2

I've been searching for a similar solution to what you are looking for, agreeing that you should be able to use an Integer array to read from and store an integer result.

A solution to this problem I found was at http://kvance.livejournal.com/1039349.html, which I found to be useful.

It doesn't quite solve the problem the way I was thinking or that way I think you want it to, instead you still specify your initial / selection values with a String array although when the ListPreference saves it back to the SharedPreferences it saves as an Integer instead of a String (doing the conversion when the user selects it), removing the need to have to convert it possibly many times throughout your application when accessing the preference value.

Ventriloquy

The referenced code is far from a complete solution and requires to override other parent methods (including constructor) in order to prevent exceptions. – Katekatee