Fragment로 커뮤니티 게시판을 만들고 있습니다 Activity에 작성한 글을 Fragment 안에 있는 커스텀 리스트뷰에 넣으려고합니다 구글링으로 방법을 찾아서 하고 있는데 java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.os.Bundle.getString(java.lang.String)' on a null object reference at com.example.project.ChatFragment.onCreateView(ChatFragment.java:33) 이렇게 오류 메세지가 뜨네요

어떻게 해결해야할지 모르겠습니다 엑티비티와 프래그먼트 코드 올립니다 혹시 몰라서 BaseAdater 코드도 올립니다

//엑티비티
package com.example.project;

import android.app.Activity;
import android.app.Fragment;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentTransaction;

public class Comunity extends AppCompatActivity {
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.comunity);
        EditText cet1=(EditText)findViewById(R.id.cet1);
        EditText cet2=(EditText)findViewById(R.id.cet2);
        Button cbtn1=(Button)findViewById(R.id.cbtn1);
        Button cbtn2=(Button)findViewById(R.id.cbtn2);
        FragmentManager manager=getSupportFragmentManager();
        FragmentTransaction transaction=manager.beginTransaction();
        ChatFragment chatFragment = new ChatFragment();
        Bundle bundle=new Bundle();

        cbtn1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                finish();
            }
        });
        cbtn2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String cTitle=cet1.getText().toString();
                String cText=cet2.getText().toString();



                bundle.getString("mainTitle",cTitle);
                bundle.getString("mainText1",cText);
                transaction.replace(R.id.cbtn2,chatFragment).commit();
                chatFragment.setArguments(bundle);

            }
        });
    }
}

//Fragment
package com.example.project;

import android.content.Intent;
import android.os.Bundle;

import androidx.fragment.app.Fragment;

import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import android.widget.TextView;

import com.google.android.material.floatingactionbutton.FloatingActionButton;

public class ChatFragment extends Fragment {
    private View view;
    private ListView chatList;
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        view=inflater.inflate(R.layout.fragment_chat,container,false);
        chatList=view.findViewById(R.id.chatList1);
        ChatListItem clAdapter=new ChatListItem();
        FloatingActionButton fab2=view.findViewById(R.id.fab2);
        TextView chatcustom1=view.findViewById(R.id.chatcustom1);
        TextView chatcustom2=view.findViewById(R.id.chatcustom2);
        Bundle bundle=getArguments();
        chatList.setAdapter(clAdapter);
        clAdapter.addChatList("맨시티 첼시 4:4 난타전","qoad123");
        clAdapter.addChatList("나이키 축구화 대박 세일","mzkxn753");
        clAdapter.addChatList("매칭 비매너 개쩌네","okc654");
        String Title=bundle.getString("mainTitle",null);
        String Text=bundle.getString("mainText1",null);
        chatcustom1.setText(Title);
        chatcustom2.setText(Text);
        fab2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(getActivity(), Comunity.class));
            }
        });
        clAdapter.addChatList(Title,Text);
        clAdapter.notifyDataSetChanged();
        return view;
    }
}

//BaseAdapter
package com.example.project;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import java.util.ArrayList;

public class ChatListItem extends BaseAdapter {
    ArrayList<ChatList> chatlist=new ArrayList<>();
    @Override
    public int getCount() {
        return chatlist.size();
    }

    @Override
    public Object getItem(int position) {
        return chatlist.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        Context c= parent.getContext();
        if (convertView==null){
            LayoutInflater li= (LayoutInflater) c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView=li.inflate(R.layout.chatcustom,parent,false);
        }
        TextView chatcustom1=convertView.findViewById(R.id.chatcustom1);
        TextView chatcustom2=convertView.findViewById(R.id.chatcustom2);

        ChatList cl=chatlist.get(position);
        chatcustom1.setText(cl.getTitle());
        chatcustom2.setText(cl.getWriter());
        return convertView;
    }
    public void addChatList(String title, String writer){
        ChatList cl=new ChatList();

        cl.setTitle(title);
        cl.setWriter(writer);

        chatlist.add(cl);
    }
}