使用片段从回收器视图中的Firebase检索数据花费太多时间

我在主要活动中使用了两个片段，第一个片段[FirstFragment]从firebase加载数据并显示在Recycler视图中，第二个片段[uploadUserCarInformation]从用户获取数据并存储在firebase中， 当应用程序启动，然后快速加载第一个片段并显示数据时，我面临一个问题。但当从第二个片段替换第一个片段时，以及从第二个片段替换回第一个片段时，需要4到5分钟才能在recyclerView中从firebase加载数据。 请告诉我在哪里修改代码

主要活动

public class MainActivity extends AppCompatActivity {
    FrameLayout simpleFrameLayout;
    TabLayout tabLayout;
    Fragment fragment1 = new FirstFragment();
    Fragment fragment2 =new SecondFragment();


    @SuppressLint("WrongViewCast")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
// get the reference of FrameLayout and TabLayout
        tabLayout=findViewById(R.id.simpleTabLayout);
        simpleFrameLayout = (FrameLayout) findViewById(R.id.simpleFrameLayout);


        FragmentManager fm = getSupportFragmentManager();
        FragmentTransaction ft = fm.beginTransaction();
        ft.replace(R.id.simpleFrameLayout, fragment1);
        ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
        ft.addToBackStack(null);
        ft.commit();

// perform setOnTabSelectedListener event on TabLayout
        tabLayout.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
            @Override
            public void onTabSelected(TabLayout.Tab tab) {
                // get the current selected tab's position and replace the fragment accordingly
                switch (tab.getPosition()) {
                    case 0:
                        tab.getIcon().setColorFilter(null);
                        fragmentReplace(fragment1,"fragment1");
                        break;
                    case 1:
                        fragmentReplace(fragment2,"fragment2");
                        break;
                }

            }


            @Override
            public void onTabUnselected(TabLayout.Tab tab) {

            }

            @Override
            public void onTabReselected(TabLayout.Tab tab) {

            }
        });

    }
    public void fragmentReplace(Fragment fragment,String fragmentName)
    {
        FragmentManager fm = getSupportFragmentManager();
        FragmentTransaction ft = fm.beginTransaction();
        ft.replace(R.id.simpleFrameLayout, fragment);
        Log.d("Running Fragment",fragmentName+ " is running");
        ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
        ft.addToBackStack(null);
        ft.commit();
    }
}

FirstFragment

public class FirstFragment extends Fragment {

    private RecyclerView mRecyclerView;
    private ImageAdapter mAdapter;

    private DatabaseReference mDatabaseRef;
    private List<carInformation> mUpload;

    View view;

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

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //retrieveAndSendData();
        Log.d("Lifecycle","onCreate called");

    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        Log.d("Lifecycle","onCreateView called");

        view=inflater.inflate(R.layout.fragment_first,container,false);
        mRecyclerView=view.findViewById(R.id.recyler_view);
        mRecyclerView.setHasFixedSize(true);
        mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
     return view;
    }


    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        Log.d("Lifecycle","onViewCreate called");
        retrieveAndSendData();


    }

    public void  retrieveAndSendData()
    {
        mUpload=new ArrayList<>();

        mDatabaseRef= FirebaseDatabase.getInstance().getReference();



        ValueEventListener valueEventListener=new ValueEventListener() {
            @Override
            //get firebase data using datasnapshot (read data)
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

                for(DataSnapshot postSnapshot : dataSnapshot.getChildren())
                {
                    String key = postSnapshot.getKey();
                    DatabaseReference databaseReference=mDatabaseRef.child(key);

                    for (DataSnapshot child:  postSnapshot.getChildren())
                    {
                        String userBookId = child.getKey();
                        if(userBookId.equals("city") )
                        {
                            break;

                        }
                        else
                        {
//                                    Toast.makeText(getActivity(),userBookId,Toast.LENGTH_LONG).show();
                            databaseReference.child(userBookId).addValueEventListener(new ValueEventListener() {
                                @Override
                                public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                                    carInformation userInformationObj=dataSnapshot.getValue(carInformation.class);
                                    mUpload.add(userInformationObj);
                                }

                                @Override
                                public void onCancelled(@NonNull DatabaseError databaseError) {

                                }
                            });
                        }

                    }

                }

                mAdapter = new ImageAdapter(getActivity(),mUpload);
                mRecyclerView.setAdapter(mAdapter);
            }


            @Override
            public void onCancelled(@NonNull DatabaseError databaseError) {
                Toast.makeText(getActivity(),databaseError.getMessage(),Toast.LENGTH_SHORT).show();
            }
        };

        mDatabaseRef.addValueEventListener(valueEventListener);

    }

public类FirstFragment扩展了Fragment{
私人回收视图mRecyclerView；
专用图像适配器mAdapter；
私有数据库引用mDatabaseRef；
私有列表多路复用器；
视图；
公共第一片段（）{
//必需的空公共构造函数
}
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
//retrieveAndSendData（）；
Log.d（“生命周期”，“调用onCreate”）；
}
@凌驾
创建视图上的公共视图（布局、充气机、视图组容器、，
Bundle savedInstanceState）{
d（“生命周期”，“调用onCreateView”）；
视图=充气机。充气（右布局。首先是碎片，容器，错误）；
mRecyclerView=view.findviewbyd（R.id.recyler\u视图）；
mRecyclerView.setHasFixedSize（true）；
setLayoutManager（新的LinearLayoutManager（getActivity（））；
返回视图；
}
@凌驾
已创建公用void onview（@NonNull视图，@Nullable Bundle savedInstanceState）{
super.onViewCreated（视图，savedInstanceState）；
Log.d（“生命周期”，“调用onViewCreate”）；
retrieveAndSendData（）；
}
public void retrieveAndSendData（）
{
mUpload=newarraylist（）；
mDatabaseRef=FirebaseDatabase.getInstance（）.getReference（）；
ValueEventListener ValueEventListener=新的ValueEventListener（）{
@凌驾
//使用datasnapshot获取firebase数据（读取数据）
public void onDataChange（@NonNull DataSnapshot DataSnapshot）{
对于（DataSnapshot postSnapshot:DataSnapshot.getChildren（））
{
String key=postsnashot.getKey（）；
DatabaseReference DatabaseReference=mDatabaseRef.child（键）；
对于（DataSnapshot子项：postSnapshot.getChildren（））
{
字符串userBookId=child.getKey（）；
if（userBookId.equals（“城市”））
{
打破
}
其他的
{
//Toast.makeText（getActivity（），userBookId，Toast.LENGTH_LONG）.show（）；
databaseReference.child（userBookId）.addValueEventListener（新的ValueEventListener（）{
@凌驾
public void onDataChange（@NonNull DataSnapshot DataSnapshot）{
carinfo userInformationObj=dataSnapshot.getValue（carinfo.class）；
添加（userInformationObj）；
}
@凌驾
已取消的公共void（@NonNull DatabaseError DatabaseError）{
}
});
}
}
}
mAdapter=newImageAdapter（getActivity（），mUpload）；
mRecyclerView.setAdapter（mAdapter）；
}
@凌驾
已取消的公共void（@NonNull DatabaseError DatabaseError）{
Toast.makeText（getActivity（），databaseError.getMessage（），Toast.LENGTH_SHORT）.show（）；
}
};
mDatabaseRef.addValueEventListener（valueEventListener）；
}

上传用户信息

    public class uploadUserCarInformation extends Fragment {
    View view;
    FirebaseAuth firebaseAuth;
    DatabaseReference databaseReference;
    StorageReference storageReference;
    private StorageTask mUploadTask;
    ImageView imageView;
    static int  PICK_IMAGE=1;
    Spinner spin;
//    mdatabase.push().getkey() -> generate uniqe id

    RadioGroup radioGroupCondition,radioGroupTransmission,radioGroupSupported;
    RadioButton radioButtonCondition,radioButtonTranmission,radioButtonSupported;
    String radioButtonConditionString,radioButtonSupportedString,radioButtonTransmissionString;
    Button addCar,signout;
    int selectedIdCondition,selectedIdTransmission,selectedIdSupported;
    String ownerName,carName,phoneNuberString,countryString;
    TextInputLayout name,carNamePlusModel,phoneNumber,country;

    carInformation car_Information=new carInformation();

    private ProgressBar progressBar;
    private Uri imageUri;

    String[] bankNames=new String[374];
    InputStream in;
    int i=0;

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }


    @RequiresApi(api = Build.VERSION_CODES.O)
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

        view=inflater.inflate(R.layout.upload_user_car_information,container,false);

        firebaseAuth=FirebaseAuth.getInstance();
        storageReference=FirebaseStorage.getInstance().getReference("uploads");

        name=view.findViewById(R.id.textFieldCarOwner);
        carNamePlusModel=view.findViewById(R.id.textFieldCarNameModel);
        phoneNumber=view.findViewById(R.id.textFieldPhoneNumber2);
        addCar=view.findViewById(R.id.addCar);
        signout=view.findViewById(R.id.sign_out);
        progressBar=view.findViewById(R.id.progress_bar);
//        progressBar.getProgressDrawable().setColorFilter(
//                Color.RED, android.graphics.PorterDuff.Mode.SRC_IN);

        radioGroupCondition=view.findViewById(R.id.radioGroupCarCondtion);
        radioGroupSupported=view.findViewById(R.id.radioGroupCarSupport);
        radioGroupTransmission=view.findViewById(R.id.radioGroupCarTransmission);

//        progressBar=new ProgressBar(getActivity());

        spin = view.findViewById(R.id.Countryspinner2);

        imageView=(ImageView) view.findViewById(R.id.selectImage);
        //imageView.setImageResource(R.drawable.select_image);

        try
        {
            InputStream fr = this.getResources().openRawResource(R.raw.cities);
            BufferedReader br = new BufferedReader(new InputStreamReader(fr));
            ArrayList<String> lines=new ArrayList<String>();
            String currentLine=br.readLine();

            while(currentLine!=null)
            {
                lines.add(currentLine);
                currentLine=br.readLine();

            }
            Collections.sort(lines);
            fr.close();    //closes the stream and release the resources

            for(String line : lines)
            {
                bankNames[i]=line;
//                System.out.println(line);
                i++;
            }

        }
        catch(IOException e)
        {
            e.printStackTrace();
        }



        ArrayAdapter<String> aa=new ArrayAdapter<String>(getActivity(),android.R.layout.simple_spinner_item,bankNames);
        aa.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        AdapterView.OnItemSelectedListener listener = new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {


            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }



        };

        spin.setOnItemSelectedListener(listener);
        spin.setAdapter(aa);


        signout.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                firebaseAuth.signOut();
        Fragment  fragment = new SecondFragment();
        FragmentManager fm = getFragmentManager();
        FragmentTransaction ft = fm.beginTransaction();
        ft.replace(R.id.simpleFrameLayout, fragment);
        ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
        ft.commit();
            }
        });
        imageView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onFileChooser();
            }
        });

        addCar.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                if(mUploadTask !=null && mUploadTask.isInProgress())
                {
                    Toast.makeText(getActivity(),"Uploading Task",Toast.LENGTH_SHORT).show();
                }
                else
                {
                    carImageAndDetailUploading();
                }

           }


        });



        return view;
    }

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

        if(requestCode == PICK_IMAGE && resultCode == RESULT_OK && data != null && data.getData() != null)
        {
                imageUri = data.getData();

                //A powerful image downloading and caching library and get image from library  for Android
                Picasso.with(getActivity()).load(imageUri).into(imageView);

        }
    }

    private void carImageAndDetailUploading()
    {
        FirebaseUser user=firebaseAuth.getCurrentUser();
        databaseReference= FirebaseDatabase.getInstance().getReference(user.getUid());



        selectedIdCondition=radioGroupCondition.getCheckedRadioButtonId();
        radioButtonCondition=view.findViewById(selectedIdCondition);
        radioButtonConditionString=radioButtonCondition.getText().toString();

        selectedIdSupported=radioGroupSupported.getCheckedRadioButtonId();
        radioButtonSupported=view.findViewById(selectedIdSupported);
        radioButtonSupportedString=radioButtonSupported.getText().toString();

        selectedIdTransmission=radioGroupTransmission.getCheckedRadioButtonId();
        radioButtonTranmission=view.findViewById(selectedIdTransmission);
        radioButtonTransmissionString=radioButtonTranmission.getText().toString();

        ownerName=name.getEditText().getText().toString().trim();
        carName=carNamePlusModel.getEditText().getText().toString().trim();
        phoneNuberString=phoneNumber.getEditText().getText().toString().trim();
        countryString=spin.getSelectedItem().toString();
        if(TextUtils.isEmpty(ownerName) || TextUtils.isEmpty(carName) || TextUtils.isEmpty(phoneNuberString) || TextUtils.isEmpty(countryString))
        {
            Toast.makeText(getActivity(),"Please fill the empty fields ",Toast.LENGTH_LONG).show();
            return; //return stooping the function to execute further
        }
        else if(imageUri == null)
        {
            Toast.makeText(getActivity(),"No file Selected ",Toast.LENGTH_LONG).show();
            return;
        }

        long phone=Long.parseLong(phoneNuberString);


        car_Information.setCarName(carName);
        car_Information.setOwnerName(ownerName);
        car_Information.setUserPhoneNumber(phone);
        car_Information.setCountry(countryString);
        car_Information.setCarCondtion(radioButtonConditionString);
        car_Information.setCarSupported(radioButtonSupportedString);
        car_Information.setCarTransmission(radioButtonTransmissionString);


        StorageReference fileReference=storageReference.child(System.currentTimeMillis()+ "." + getFileExtension(imageUri));
        mUploadTask =  fileReference.putFile(imageUri)
                .addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
                    @Override
                    public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {

                        //below code user can see 100 % progress bar for 5 sec
                        Handler handler = new Handler();
                        handler.postDelayed(new Runnable() {
                            @Override
                            public void run() {
                                progressBar.setProgress(0);
                            }
                        },5000);

                        String uniqueKey=databaseReference.push().getKey();
                        Task<Uri> urlTask = taskSnapshot.getStorage().getDownloadUrl();
                        while (!urlTask.isSuccessful());
                        Uri downloadUrl = urlTask.getResult();
                        car_Information.setImageUrl(downloadUrl.toString());
                        car_Information.setUnique_key(uniqueKey);
//                        databaseReference.child("car details"+car_Information.getUnique_key());
//                        databaseReference.child("car details"+car_Information.getUnique_key()).setValue(car_Information);
                        databaseReference.child(car_Information.getUnique_key());
                        databaseReference.child(car_Information.getUnique_key()).setValue(car_Information);

                        Toast.makeText(getActivity(),"Successfully Upload",Toast.LENGTH_SHORT).show();




                        clear_editText();



                    }
                })
                .addOnFailureListener(new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception e) {
                        Toast.makeText(getActivity(),e.getMessage(),Toast.LENGTH_SHORT).show();
                    }
                })
                .addOnProgressListener(new OnProgressListener<UploadTask.TaskSnapshot>() {
                    @Override
                    public void onProgress(UploadTask.TaskSnapshot taskSnapshot) {
                        double progress=(100.0 * taskSnapshot.getBytesTransferred() / taskSnapshot.getTotalByteCount());
                        progressBar.setProgress((int) progress);
                    }
                });
    }


    private  void onFileChooser()
    {
        Intent intent =new Intent(Intent.ACTION_GET_CONTENT);
        intent.setType("image/*");
        startActivityForResult(intent,PICK_IMAGE);
        //startActivityForResult(Intent.createChooser(intent,"Select Picture"),PICK_IMAGE);
    }
    private String getFileExtension(Uri uri)
    {
        //this method for get file extension
        ContentResolver cR=getActivity().getContentResolver();
        MimeTypeMap mime=MimeTypeMap.getSingleton();
        return mime.getExtensionFromMimeType(cR.getType(uri));
    }

    private void clear_editText()
    {
        name.getEditText().setText(" ");
        carNamePlusModel.getEditText().setText(" ");
        phoneNumber.getEditText().setText(" ");
    }
}

public类uploadUserCarInformation扩展片段{
视图；
FirebaseAuth FirebaseAuth；
数据库参考数据库参考；
StorageReference-StorageReference；
专用存储任务mUploadTask；
图像视图图像视图；
静态int PICK_IMAGE=1；
旋转器旋转；
//mdatabase.push（）.getkey（）->生成uniqe id
支持的放射组放射组条件、放射组传输、放射组；
RadioButton RadioButton条件、RadioButton传输、RadioButton支持；
字符串radioButtonConditionString、RadioButtonSupportString、radioButtonTransmissionString；
按钮addCar，注销；
int selectedCondition，selectedTransmission，selectedSupported；
字符串所有者名称、carName、phoneNuberString、countryString；
TextInputLayout名称、carNamePlusModel、电话号码、国家/地区；
carInformation car_Information=新carInformation（）；
私人ProgressBar ProgressBar；
私有Uri-imageUri；
字符串[]bankNames=新字符串[374]；
输入流输入；
int i=0；
@凌驾
创建时的公共void（@Nullable Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
}
@RequiresApi（api=Build.VERSION\u CODES.O）
@凌驾
创建视图时的公共视图（@NonNull LayoutInflater inflater、@Nullable ViewGroup container、@Nullable Bundle savedInstanceState）{
视图=充气机。充气（右布局。上传用户车辆信息，容器，错误）；
firebaseAuth=firebaseAuth.getInstance（）；
storageReference=FirebaseStorage.getInstance（）.getReference（“上载”）；
name=view.findviewbyd（R.id.textFieldCarOwner）；
carNamePlusModel=view.findviewbyd（R.id.textfieldcanamemodel）；
phoneNumber=view.findViewById（R.id.textFieldPhoneNumber2