ArrayList of object will not add objects

Question

I try to add journalNote objects in array list journalList, but they will not be inserted. I want to use this array list to draw a barchart in another activity with the respectiv data.

My array list is in this fragment:


public class MyJournalFragment extends Fragment {

    public MyJournalFragment() {
        // Required empty public constructor
    }


    private FloatingActionButton floatingActionButton;
    Button btnShowGraph;
    private Intent intent;
    public static final int REQUEST_CODE = 200;

    public static final int REQUEST_CODE_EDIT = 300;

    public static final String EDIT_JNOTE = "editJNote";

    public int poz;

    private ListView listView;
    List<JournalNote> notesList = new ArrayList<JournalNote>();

    //Ce era in onCreate ~= onCreateView
    //nu E setOnContentView pt fragmente, ai alte metode
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View view = inflater.inflate(R.layout.fragment_my_journal, container, false);

        //in activity la seminar era pus in onCreate, dupa startActivity
        listView = (ListView) view.findViewById(R.id.listView);
        //set the adapter, etc

      //  FloatingActionButton fab = (FloatingActionButton) view.findViewById(R.id.floatingActionButton);
        floatingActionButton = (FloatingActionButton) view.findViewById(R.id.floatingActionButton);
        floatingActionButton.setOnClickListener(new View.OnClickListener() {

         //de ce punem intentul in onClickView?
            //Aici punem intentul si start activity
         //this is what runs when you click the button
            @Override
            public void onClick(View view) {

                intent = new Intent(getActivity().getApplicationContext(), Add_Journal_Note_Activity.class);
                Serializable data = intent.getSerializableExtra(Add_Journal_Note_Activity.ADD_JNOTE);
                startActivityForResult(intent, REQUEST_CODE);
            }
        });

//Here I create the new array list and start the barchart activity //When I take it in debugger mode my new list has 0 elements and my old one has as many objects as I inserted them manually //BarChart Tip Notita btnShowGraph = (Button) view.findViewById(R.id.buttonShowGraph); btnShowGraph.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { ArrayList journalList = new ArrayList(); for (JournalNote journalNote : notesList) journalList.add(journalNote);

                Intent intent1 = new Intent( getActivity().getApplicationContext() , BarChart_Journal_Activity.class);
                intent1.putExtra("journalList",journalList);
                startActivity(intent1);
            }
        });

        //Modifica notita
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int position, long id) {

                poz = position;
                intent = new Intent(getActivity().getApplicationContext(), Add_Journal_Note_Activity.class);
                intent.putExtra(EDIT_JNOTE, notesList.get(position));
                startActivityForResult(intent, REQUEST_CODE_EDIT);
            }
        });

        listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> adapterView, View view, int position, long id) {

                final JournalNote notes = notesList.get(position);

                final JournalAdapter adapter = (JournalAdapter) listView.getAdapter();

                AlertDialog dialog = new AlertDialog.Builder(getActivity())
                        .setTitle("Confirmare stergere")
                        .setMessage("Sigur doriti stergerea?")
                        .setNegativeButton("No", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialogInterface, int i) {
                                Toast.makeText(getActivity(), "Nu s-a sters nimic!",
                                        Toast.LENGTH_LONG).show();
                                dialogInterface.cancel();
                            }
                        }).setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialogInterface, int i) {
                                notesList.remove(notes);
                                adapter.notifyDataSetChanged();
                                Toast.makeText(getActivity(), "S-a sters filmul: "+notes.toString(),
                                        Toast.LENGTH_LONG).show();
                                dialogInterface.cancel();
                            }
                        }).create();

                dialog.show();

                return true;
            }
        });

        return view;
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == REQUEST_CODE && resultCode == Activity.RESULT_OK && data != null) {
            JournalNote notes = (JournalNote) data.getSerializableExtra(Add_Journal_Note_Activity.ADD_JNOTE);

            if (notes != null) {

                notesList.add(notes);


                JournalAdapter adapter = new JournalAdapter(getActivity(), R.layout.journal_listview,
                        notesList, getLayoutInflater()){
                    @NonNull
                    @Override
                    public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
                        View view = super.getView(position, convertView, parent);

                        JournalNote notes =  notesList.get(position);
                        System.out.println(notes.getCurNote().toString());
                        TextView tvMessage = view.findViewById(R.id.mesaj);
                        if(notes.getCurNote().toString() == "LECTURE" )
                            tvMessage.setTextColor(Color.GREEN);
                        else
                            System.out.println(notes.getCurNote().toString());
                          if(notes.getCurNote().toString()== "LAB")
                            tvMessage.setTextColor(Color.BLUE);
                       else
                              System.out.println(notes.getCurNote().toString());
                        if(notes.getCurNote().toString() == "OTHERS")
                            tvMessage.setTextColor(Color.RED);

                        return view;

                    }
                };

                listView.setAdapter(adapter);
            }
        }
        else
        if (requestCode == REQUEST_CODE_EDIT && resultCode == Activity.RESULT_OK && data != null) {
            JournalNote notes = (JournalNote) data.getSerializableExtra(ADD_JNOTE);
            {
                if (notes!=null)
                {
                    notesList.get(poz).setTitle(notes.getTitle());
                    notesList.get(poz).setData(notes.getData());
                    notesList.get(poz).setMessage(notes.getMessage());
                    notesList.get(poz).setNotetype(notes.getNotetype());
                    notesList.get(poz).setCurNote(notes.getCurNote());

                    JournalAdapter adapter = new JournalAdapter(getActivity(), R.layout.journal_listview,
                            notesList, getLayoutInflater()){
                        @NonNull
                        @Override
                        public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
                            View view = super.getView(position, convertView, parent);

                            JournalNote notes =  notesList.get(position);

                            TextView tvMessage = view.findViewById(R.id.mesaj);
                            if(notes.getCurNote().toString() == "LECTURE" )
                                tvMessage.setTextColor(Color.GREEN);
                         else if(notes.getCurNote().toString()== "LAB")
                                tvMessage.setTextColor(Color.BLUE);
                         else
                         if(notes.getCurNote().toString() == "OTHERS")
                             tvMessage.setTextColor(Color.RED);

                            return view;
                        }
                    };
                    listView.setAdapter(adapter);
                }
            }
        }
    }
}

BArcchart Activity:
public class BarChart_Journal_Activity extends AppCompatActivity {

    List<JournalNote> journalList;
    LinearLayout layout;
    Map<String, Integer> source;

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

        Intent intent = getIntent();

        journalList = (ArrayList<JournalNote>) intent.getSerializableExtra("jounalList");

        source = getSource(journalList);

        layout = findViewById(R.id.layoutBar);
        layout.addView(new BarChartView(getApplicationContext(), source));
        }

        private Map<String, Integer> getSource( List<JournalNote> notes)
        {
            if(notes == null || notes.isEmpty())
                return new HashMap<>();
            else{
                Map<String,Integer> results = new HashMap<>();
                for(JournalNote journalNote: notes)
                    if(results.containsKey(journalNote.getNotetype()))
                        results.put(journalNote.getNotetype().toString(),  results.get(journalNote.getNotetype())+1);

                    else { results.put(journalNote.getNotetype().toString(),1);}


                return results;
            }

        }

}

Update: And here is my JournalNote Class:

package ro.ase.proiect_draft;

import java.io.Serializable;
import java.util.Date;
import java.util.UUID;



public class JournalNote implements Serializable {

    private String id;
    private String title;
    private Date data;
    private String message;
    private NoteType notetype;
    private CurricularNote curNote;

    public JournalNote(String title, Date data, String message, NoteType notetype, CurricularNote curNote) {
        id = UUID.randomUUID().toString();
        this.title = title;
        this.data = data;
        this.message = message;
        this.notetype = notetype;
        this.curNote = curNote;
    }


    public String getId() {
        return id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public Date getData() {
        return data;
    }

    public void setData(Date data) {
        this.data = data;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public NoteType getNotetype() {
        return notetype;
    }

    public void setNotetype(NoteType notetype) {
        this.notetype = notetype;
    }

    public CurricularNote getCurNote() {
        return curNote;
    }

    public void setCurNote(CurricularNote curNote) {
        this.curNote = curNote;
    }

    @Override
    public String toString() {
        return "JournalNote{" +
                "title='" + title + '\'' +
                ", data=" + data +
                ", message='" + message + '\'' +
                ", notetype=" + notetype +
                ", curNote=" + curNote +
                '}';
    }

    public enum NoteType {FAVORITE, IMPORTANT, REMINDMELATER}

    public enum CurricularNote {LECTURE, LAB, OTHERS}
}

hope [this](https://stackoverflow.com/questions/13601883/how-to-pass-arraylist-of-objects-from-one-to-another-activity-using-intent-in-an) helps — Sekiro, Jan 08 '21 at 17:03
Does this answer your question? [How to pass ArrayList of Objects from one to another activity using Intent in android?](https://stackoverflow.com/questions/13601883/how-to-pass-arraylist-of-objects-from-one-to-another-activity-using-intent-in-an) — Sekiro, Jan 08 '21 at 17:04
@MrudulTora I updated the code with the class. Do you know how I could solve it? — programmingDracula2699, Jan 08 '21 at 18:53
Please remember next time while uploading code , you properly indent it. Some part of your code is not properly indented. — Mrudul Tora, Jan 09 '21 at 09:37

score 0 · Answer 1 · answered Jan 09 '21 at 09:35

When you start Barchart Activity your new list has 0 elements because your passing the list in intent in wrong form. Firstly, in JournalNote class implement Parcelable instead of Serializable. So, your final JournalNote class should look like this.

import android.os.Parcel;
import android.os.Parcelable;

import java.util.Date;
import java.util.UUID;

public class JournalNote implements Parcelable {

    private String id;
    private String title;
    private Date data;
    private String message;
    private NoteType notetype;
    private CurricularNote curNote;

    public JournalNote(String title, Date data, String message, NoteType notetype, CurricularNote curNote) {
        id = UUID.randomUUID().toString();
        this.title = title;
        this.data = data;
        this.message = message;
        this.notetype = notetype;
        this.curNote = curNote;
    }


    protected JournalNote(Parcel in) {
        id = in.readString();
        title = in.readString();
        message = in.readString();
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeString(id);
        dest.writeString(title);
        dest.writeString(message);
    }

    @Override
    public int describeContents() {
        return 0;
    }

    public static final Creator<JournalNote> CREATOR = new Creator<JournalNote>() {
        @Override
        public JournalNote createFromParcel(Parcel in) {
            return new JournalNote(in);
        }

        @Override
        public JournalNote[] newArray(int size) {
            return new JournalNote[size];
        }
    };

    public String getId() {
        return id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public Date getData() {
        return data;
    }

    public void setData(Date data) {
        this.data = data;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public NoteType getNotetype() {
        return notetype;
    }

    public void setNotetype(NoteType notetype) {
        this.notetype = notetype;
    }

    public CurricularNote getCurNote() {
        return curNote;
    }

    public void setCurNote(CurricularNote curNote) {
        this.curNote = curNote;
    }

    @Override
    public String toString() {
        return "JournalNote{" +
                "title='" + title + '\'' +
                ", data=" + data +
                ", message='" + message + '\'' +
                ", notetype=" + notetype +
                ", curNote=" + curNote +
                '}';
    }

    public enum NoteType {FAVORITE, IMPORTANT, REMINDMELATER}

    public enum CurricularNote {LECTURE, LAB, OTHERS}
}

Then while passing the complete list through intent, write the code like this,

Intent intent1 = new Intent( getActivity().getApplicationContext() , BarChart_Journal_Activity.class);
                intent1.putParcelableArrayList("journalList",journalList);
                startActivity(intent1);

By implementing parcelable in JournalNote class you can pass complete list from one Activity to another.

ArrayList of object will not add objects

1 Answers1