Null Pointer trying to add items to an SQLiteDataBase after checking checkbox in Dialog

Question

I am having an issue with a checkbox and adding items to a database in Sql. The issue is that I am getting a null pointer exception at line 171 which is:

    db.addTimer(new TimerClass(tagval1, String.valueOf(startTime*60)));

this entry is basically a mirror to the following line which I use to add a default value to my database if it is now created:

    db.addTimer(new TimerClass("Lipton", "180"));

that being said the checkbox value that I want to check to trigger the first line is set within the show dialog code listed below:

    public void showDialog(){
    cusd = new Dialog(MainActivity.this,R.style.Theme_MultiTimer_Dialog);
    cusd.setContentView(R.layout.dialogbox);
    canlbtn = (Button) cusd.findViewById(R.id.cancelbtn);
    sbtbtn = (Button) cusd.findViewById(R.id.submitbtn);        
    minnp = (NumberPicker) cusd.findViewById(R.id.numberPicker1);
    secnp = (NumberPicker) cusd.findViewById(R.id.numberPicker2);
    tagvalue = (EditText) cusd.findViewById(R.id.tagname);
    ckb = (CheckBox) cusd.findViewById(R.id.savecheckBox);
    ckb.setOnClickListener(this);
    canlbtn.setOnClickListener(this);
    sbtbtn.setOnClickListener(this);
    minnp.setMaxValue(59);
    minnp.setMinValue(0);
    minnp.setWrapSelectorWheel(false);
    minnp.setOnValueChangedListener(this);
    secnp.setMaxValue(59);
    secnp.setMinValue(0);
    secnp.setWrapSelectorWheel(false);
    secnp.setOnValueChangedListener(this);
    cusd.show();
}

now I also have in the same dialog two (2) number pickers and an EditText that I pull values from comfortably. The issue is when I try to add the entry into the database itself. Below is the addtimer code which is generic code to add to a database and as specified above it works comfortably with the second line of code that I listed above.

       public void addTimer(TimerClass timers){
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(KEY_TAG, timers.getTag());
    values.put(KEY_TIMEINSECONDS, timers.gettimeInSeconds());
    db.insert(TABLE_NAME, null, values);
    db.close();
}

please see below where I declared the necessary items and also the code where I instantiated the different code.

    public class MainActivity extends Activity implements NumberPicker.OnValueChangeListener, OnClickListener, OnItemSelectedListener{
//--------------------------------------------------------------------------------------------------
Button dgbtn, abbtn, exbtn, canlbtn, sbtbtn, starest, clrbtn, deltbtn;
EditText tagvalue;
TextView timeRemaining, titleTvRight, titleTvLeft;
NumberPicker minnp, secnp;
Dialog cusd;
ProgressBar titleProgressBar;
TimerDataBaseHandler db;
Spinner s;
CheckBox ckb;
protected CountDownTimer timerCountDownTimer;
private boolean timerHasStarted = false;
private TextView timeElapsedView;
protected int startTime=0;
protected int val1, val2, val3, val4;
protected String tagval1;
boolean customTitleSupported, savechkbx;
File mydb ;
//--------------------------------------------------------------------------------------------------
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    customTitleSupported= requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
    setContentView(R.layout.main);
    getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.custom_title);
    TimerDataBaseHandler db = new TimerDataBaseHandler(getApplicationContext());
    mydb = new File("/data/data/com.vertygoeclypse.multitimer/databases/TimerManager");
    if(mydb.exists()){
        Log.i("VertygoEclypse", "True");
    } else {
        Log.i("VertygoEclypse", "false");
        db.addTimer(new TimerClass("Lipton", "180"));
    }
//--------------------------------------------------------------------------------------------------
    dgbtn = (Button) findViewById(R.id.dialogbtn);
    abbtn = (Button) findViewById(R.id.aboutbtn);
    exbtn = (Button) findViewById(R.id.exitbtn);
    starest =  (Button) findViewById(R.id.startresetbtn);
    clrbtn = (Button) findViewById(R.id.clearvaluesbutton);
    deltbtn = (Button)     findViewById(R.id.deletevaluesbutton);
    timeRemaining = (TextView) findViewById(R.id.timeremainingview);
    titleTvLeft = (TextView)findViewById(R.id.titleTVLeft);
    titleTvRight = (TextView)findViewById(R.id.titleTVRight);
    titleProgressBar = (ProgressBar)findViewById(R.id.leadprogressBar);
    s = (Spinner)findViewById(R.id.timerspinner);
//--------------------------------------------------------------------------------------------------
    dgbtn.setOnClickListener(this);
    abbtn.setOnClickListener(this);
    exbtn.setOnClickListener(this);
    starest.setOnClickListener(this);
    clrbtn.setOnClickListener(this);
    deltbtn.setOnClickListener(this);
    s.setOnItemSelectedListener(this);

Can anyone please help on this, I am sure that the issue is something I am missing but, being new to android programming, I guess I cannot see it.

Also please see the logcat captures below, where I was pointed to line 171 as the place of the issue.

    01-07 21:58:49.650    1971-1971/com.vertygoeclypse.multitimer I/VertygoEclypse﹕ True
    01-07 21:58:49.678    1971-1971/com.vertygoeclypse.multitimer D/dalvikvm﹕ GC_FOR_ALLOC freed 74K, 10% free 2906K/3212K, paused 3ms, total 3ms
    01-07 21:58:49.698    1971-1971/com.vertygoeclypse.multitimer D/libEGL﹕ loaded /system/lib/egl/libEGL_genymotion.so
    01-07 21:58:49.698    1971-1971/com.vertygoeclypse.multitimer D/﹕ HostConnection::get() New Host Connection established 0xb8db9bf0, tid 1971
    01-07 21:58:49.710    1971-1971/com.vertygoeclypse.multitimer D/libEGL﹕ loaded /system/lib/egl/libGLESv1_CM_genymotion.so
    01-07 21:58:49.710    1971-1971/com.vertygoeclypse.multitimer D/libEGL﹕ loaded /system/lib/egl/libGLESv2_genymotion.so
    01-07 21:58:49.774    1971-1971/com.vertygoeclypse.multitimer W/EGL_genymotion﹕ eglSurfaceAttrib not implemented
    01-07 21:58:49.774    1971-1971/com.vertygoeclypse.multitimer E/OpenGLRenderer﹕ Getting MAX_TEXTURE_SIZE from GradienCache
    01-07 21:58:49.782    1971-1971/com.vertygoeclypse.multitimer E/OpenGLRenderer﹕ Getting MAX_TEXTURE_SIZE from Caches::initConstraints()
    01-07 21:58:49.782    1971-1971/com.vertygoeclypse.multitimer D/OpenGLRenderer﹕ Enabling debug mode 0
    01-07 21:59:22.058    1971-1971/com.vertygoeclypse.multitimer D/dalvikvm﹕ GC_FOR_ALLOC freed 44K, 8% free 3327K/3612K, paused 7ms, total 7ms
    01-07 21:59:22.070    1971-1971/com.vertygoeclypse.multitimer D/dalvikvm﹕ GC_FOR_ALLOC freed 15K, 8% free 3715K/4028K, paused 2ms, total 2ms
    01-07 21:59:22.154    1971-1971/com.vertygoeclypse.multitimer W/EGL_genymotion﹕ eglSurfaceAttrib not implemented
    01-07 21:59:22.238    1971-1971/com.vertygoeclypse.multitimer V/RenderScript﹕ 0xb8eb9850 Launching thread(s), CPUs 4
    01-07 21:59:23.826    1971-1971/com.vertygoeclypse.multitimer D/dalvikvm﹕ GC_FOR_ALLOC freed 60K, 7% free 4167K/4460K, paused 1ms, total 2ms
    01-07 21:59:27.154    1971-1971/com.vertygoeclypse.multitimer D/AndroidRuntime﹕ Shutting down VM
    01-07 21:59:27.154    1971-1971/com.vertygoeclypse.multitimer W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0xa4bee648)
    01-07 21:59:27.158    1971-1971/com.vertygoeclypse.multitimer E/AndroidRuntime﹕ FATAL EXCEPTION: main
    java.lang.NullPointerException
        at com.vertygoeclypse.multitimer.MainActivity.onClick(MainActivity.java:171)
        at android.view.View.performClick(View.java:4240)
        at android.view.View$PerformClick.run(View.java:17721)
        at android.os.Handler.handleCallback(Handler.java:730)
        at android.os.Handler.dispatchMessage(Handler.java:92)
        at android.os.Looper.loop(Looper.java:137)
        at android.app.ActivityThread.main(ActivityThread.java:5103)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:525)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
        at dalvik.system.NativeStart.main(Native Method)

Thanks in advance all who can assist me, I appreciate your time and effort.

regards

cchinchoy

Answer 1

The solution came to me after a lot of code trial and error. I realized that the code to the check box is wrong and that :

    ckb.setOnClickListener(this);

into this:

    ckb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener()

what this does is that it brings the following into play:

            ckb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton compoundButton, boolean isChecked) {
            if(isChecked){
                savechkbx = true;
            } else {
                savechkbx = false;
            }
        }
    });

I have created a declaration of the savechkbx as a Boolean and then set it to false. This is to counterbalance the fact that I had the checkbox set to true in the xml file like this:

        <CheckBox
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginLeft="20sp"
    android:layout_marginRight="5sp"
    android:layout_marginTop="1sp"
    android:text="Saver Timer for Later use!!!"
    android:id="@+id/savecheckBox"
    android:checked="true" >
    </CheckBox>

With that being said what then happens is that on the submit button check, I have the following:

            if(savechkbx==true){
            db.addTimer(new TimerClass(tagval1, temp2));
             }

else it returns nothing. I have to modify the code to make it cleaner however. This solves the question.