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Application crash due to NullPointerException

I work with a list that, when clicked, opens a dialog box containing an edittext and a button. When a button is clicked, the value entered in editText is saved in the textView element from the listview element that was previously clicked. The problem is that the value was no longer saved if I reopened the application. I tried to save it using sharedPrefences, but it crashes and shows 3 nullpointerexception and cannot handle them.

Here is my:

Carnet.java

package com.cngcnasaud.orar;

import android.app.TabActivity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TabHost;
import android.widget.TabHost.TabSpec;

@SuppressWarnings("deprecation")
public class Carnet extends TabActivity {
    // TabSpec Names
    private static final String NOTA_SPEC = "Note";
    private static final String ABSENTE_SPEC = "Absente";
    private static final String MEDII_SPEC = "Medii";


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.carnet);

        TabHost tabHost = getTabHost();


        TabSpec NotaSpec = tabHost.newTabSpec(NOTA_SPEC);
        // Tab Icon
        NotaSpec.setIndicator(NOTA_SPEC, getResources().getDrawable(R.drawable.nota_open));
        Intent notaIntent = new Intent(this, Note.class);
        // Tab Content
        NotaSpec.setContent(notaIntent);


        TabSpec AbsenteSpec = tabHost.newTabSpec(ABSENTE_SPEC);
        AbsenteSpec.setIndicator(ABSENTE_SPEC, getResources().getDrawable(R.drawable.nota_open));
        Intent absenteIntent = new Intent(this, Absente.class);
        AbsenteSpec.setContent(absenteIntent);

        TabSpec MediiSpec = tabHost.newTabSpec(MEDII_SPEC);
        AbsenteSpec.setIndicator(MEDII_SPEC, getResources().getDrawable(R.drawable.nota_open));
        Intent mediiIntent = new Intent(this, MediiL.class);
        AbsenteSpec.setContent(mediiIntent);


        // Adding all TabSpec to TabHost
        tabHost.addTab(NotaSpec); 
        tabHost.addTab(AbsenteSpec); 
        tabHost.addTab(MediiSpec);

    }
}

Note.java

package com.cngcnasaud.orar;

import java.util.ArrayList;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;
import android.view.Menu;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.TextView;

public class Note extends Activity {

    private static final ListAdapter NoteAdapter = null;
    ListView lv;
    Context context;
    ArrayList<?> prgmName;
    TextView text;

    public static String[] prgmNameList = { "Romana   - ", "Matematica   - ",
            "Lb. Engleza   - ", "Lb. Germana/Franceza - ", "Istorie   - ",
            "Geografie   - ", "Biologie   - ", "Fizica   - ", "Ed. Fizica   - " };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.note_listview);

        text = (TextView) findViewById(R.id.textView2);

        context = this;

        lv = (ListView) findViewById(R.id.listView);
        lv.setAdapter(new NoteAdapter(this, prgmNameList, null));

    }

    @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
    protected void onStop() {
        // TODO Auto-generated method stub

        NoteAdapter adapter = (NoteAdapter) lv.getAdapter();

        // Variable is public for clarity.
        String toSave = EncodeDecode.encode(adapter.savedEntries);
        SharedPreferences.Editor editor = getSharedPreferences("LV Data",
                MODE_PRIVATE).edit();
        editor.putString("TVEntries", toSave);
        editor.commit();
    }

    @Override
    protected void onResume() {
        // TODO Auto-generated method stub

        SharedPreferences prefs = getSharedPreferences("LV Data", MODE_PRIVATE);
        String encoded = prefs.getString("TVEntries", "");

        String[] entries;
        if (encoded.equals(""))
            entries = null;
        else
            entries = EncodeDecode.decode(encoded);

        NoteAdapter adapter = (NoteAdapter) lv.getAdapter();
        adapter.savedEntries = entries;
        lv.setAdapter(adapter);

        super.onResume();
    }

}

And NoteAdapter.java:

package com.cngcnasaud.orar;

import java.util.Arrays;

import android.app.Dialog;
import android.content.Context;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;

public class NoteAdapter extends BaseAdapter {

    String[] result;
    Context context;
    int[] imageId;
    private static LayoutInflater inflater = null;
    private Dialog dialog;
    String[] savedEntries;
    String[] saved = null;

    public NoteAdapter(Note note, String[] saved, String[] prgmNameList) {
        // TODO Auto-generated constructor stub
        result = prgmNameList;
        context = note;
        inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        if (saved == null) {
            savedEntries = new String[result.length];
            Arrays.fill(savedEntries, "");
        } else
            savedEntries = saved;

    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return result.length;
    }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return savedEntries[position];
    }

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    public class Holder {
        TextView tv;
        ImageView img;
        public TextView text;
    }

    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub

        final Holder holder = new Holder();
        View rowView;
        rowView = inflater.inflate(R.layout.note_items, null);
        holder.tv = (TextView) rowView.findViewById(R.id.textView1);
        holder.text = (TextView) rowView.findViewById(R.id.textView2);
        holder.text.setText(savedEntries[position]);
        holder.img = (ImageView) rowView.findViewById(R.id.imageView1);

        rowView.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                dialog = new Dialog(context);
                dialog.setContentView(R.layout.dialog);
                dialog.setTitle("Materie:" + result[position]);

                final EditText txtMode = (EditText) dialog
                        .findViewById(R.id.dialog);
                Button btnSave = (Button) dialog.findViewById(R.id.bsave);

                btnSave.setOnClickListener(new OnClickListener() {

                    @Override
                    public void onClick(View v) {

                        String data = txtMode.getText().toString();
                        holder.text.setText(data);

                        savedEntries[position] = data;

                        dialog.dismiss();
                        Log.d("data", data);
                    }
                });
                dialog.show();
            }

        });
        return rowView;
    }

}

LogCat:

04-18 19:27:28.558: E/AndroidRuntime(1419): FATAL EXCEPTION: main
04-18 19:27:28.558: E/AndroidRuntime(1419): Process: com.cngcnasaud.orar, PID: 1419
04-18 19:27:28.558: E/AndroidRuntime(1419): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.cngcnasaud.orar/com.cngcnasaud.orar.Carnet}: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.cngcnasaud.orar/com.cngcnasaud.orar.Note}: java.lang.NullPointerException
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.ActivityThread.access$800(ActivityThread.java:135)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.os.Handler.dispatchMessage(Handler.java:102)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.os.Looper.loop(Looper.java:136)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.ActivityThread.main(ActivityThread.java:5017)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at java.lang.reflect.Method.invokeNative(Native Method)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at java.lang.reflect.Method.invoke(Method.java:515)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at dalvik.system.NativeStart.main(Native Method)
04-18 19:27:28.558: E/AndroidRuntime(1419): Caused by: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.cngcnasaud.orar/com.cngcnasaud.orar.Note}: java.lang.NullPointerException
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.ActivityThread.startActivityNow(ActivityThread.java:2035)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:135)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.LocalActivityManager.startActivity(LocalActivityManager.java:347)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:749)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.widget.TabHost.setCurrentTab(TabHost.java:413)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.widget.TabHost.addTab(TabHost.java:240)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at com.cngcnasaud.orar.Carnet.onCreate(Carnet.java:45)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.Activity.performCreate(Activity.java:5231)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
04-18 19:27:28.558: E/AndroidRuntime(1419):     ... 11 more
04-18 19:27:28.558: E/AndroidRuntime(1419): Caused by: java.lang.NullPointerException
04-18 19:27:28.558: E/AndroidRuntime(1419):     at com.cngcnasaud.orar.NoteAdapter.getCount(NoteAdapter.java:46)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.widget.ListView.setAdapter(ListView.java:480)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at com.cngcnasaud.orar.Note.onCreate(Note.java:34)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.Activity.performCreate(Activity.java:5231)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
04-18 19:27:28.558: E/AndroidRuntime(1419):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
04-18 19:27:28.558: E/AndroidRuntime(1419):     ... 21 more

Carnet.java line 45:

tabHost.addTab(NotaSpec);

NoteAdapter.java line 46:

return result.length;

Line Note.java 34:

 lv.setAdapter(new NoteAdapter(this, prgmNameList, null));
+4
source share
1

:

NoteAdapter.java 46:

return result.length;

, :

public NoteAdapter(Note note, String[] saved, String[] prgmNameList) {
    // TODO Auto-generated constructor stub
    result = prgmNameList;

null ( , ):

Note.java 34:

lv.setAdapter(new NoteAdapter(this, prgmNameList, null));

, (public static final).

+3

Source: https://habr.com/ru/post/1537150/

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