android - 将数据 fragment 传递到同一 Activity 中的 fragment

Question

我有一些问题想询问有关在 Activity 中将数据从一个 fragment 传递到另一个 fragment 的问题。我不知道该怎么做。有人可以帮忙吗？ 这是我的代码。

ShareFragment.java

package com.example.user8.myapplication;


import android.app.AlertDialog;
import android.app.DatePickerDialog;
import android.app.Dialog;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.DialogFragment;
import android.support.v4.app.Fragment;
import android.text.TextUtils;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.DatePicker;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;

import java.text.DateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.Locale;


/**    
 * A simple {@link Fragment} subclass.
 */
public class ShareFragment extends Fragment implements             AdapterView.OnItemSelectedListener{

private Spinner spinner1,spinner2,spinner3;
private Button btn_submit,btn_selDate;
private FirebaseAuth auth;
FirebaseUser firebaseUser;

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

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View v = inflater.inflate(R.layout.fragment_share, container, false);

    btn_selDate = (Button) v.findViewById(R.id.btn_selDate);

    btn_selDate.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            // Initialize a new date picker dialog fragment
            DialogFragment dFragment = new DatePickerFragment();

            // Show the date picker dialog fragment
            dFragment.show(getFragmentManager(), "Date Picker");

        }
    });

    btn_submit = (Button) v.findViewById(R.id.btn_submit_food);

    spinner1 = (Spinner)v.findViewById(R.id.spinner_selectFood);
    ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(getContext(),R.array.spinner_food,R.layout.support_simple_spinner_dropdown_item);
    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinner1.setAdapter(adapter);
    spinner1.setOnItemSelectedListener(this);

    spinner3 = (Spinner)v.findViewById(R.id.spinner_selectTime);
    ArrayAdapter<CharSequence> adapter3 = ArrayAdapter.createFromResource(getContext(),R.array.spinner_time,R.layout.support_simple_spinner_dropdown_item);
    adapter3.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinner3.setAdapter(adapter3);
    spinner3.setOnItemSelectedListener(this);

    auth = FirebaseAuth.getInstance();

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

            DatabaseReference ref = FirebaseDatabase.getInstance().getReference("Food").push();
            firebaseUser = auth.getCurrentUser();
            String uid = firebaseUser.getUid();
            String u_food = spinner1.getSelectedItem().toString();
            String u_time= spinner3.getSelectedItem().toString();

            Food myFood = new Food(uid,u_food,"formatteddate",u_time);//data pass to here to save into firebase
            ref.setValue(myFood).addOnCompleteListener(new OnCompleteListener<Void>() {
                @Override
                public void onComplete(@NonNull Task<Void> task) {
                    if (task.isSuccessful()) {
                        Toast.makeText(getContext(), getString(R.string.share_food_success_msg), Toast.LENGTH_SHORT).show();
                        getActivity().finish();
                        startActivity(new Intent(getContext(), Main2Activity.class));
                    } else {
                        Toast.makeText(getContext(),  getString(R.string.share_food_fail_msg), Toast.LENGTH_SHORT).show();
                        getActivity().finish();
                        startActivity(new Intent(getContext(), Main3Activity.class));
                    }
                }
            });
        }
    });
    return v;
}

public static class DatePickerFragment extends DialogFragment implements DatePickerDialog.OnDateSetListener {

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final Calendar calendar = Calendar.getInstance();
        int year = calendar.get(Calendar.YEAR);
        int month = calendar.get(Calendar.MONTH);
        int day = calendar.get(Calendar.DAY_OF_MONTH);

        DatePickerDialog dpd = new DatePickerDialog(getActivity(),
                AlertDialog.THEME_HOLO_LIGHT, this, year, month, day);

        /*
            add(int field, int value)
                Adds the given amount to a Calendar field.
         */
        // Add 3 days to Calendar
        calendar.add(Calendar.DATE, 3);

        dpd.getDatePicker().setMaxDate(calendar.getTimeInMillis());

        // Subtract 6 days from Calendar updated date
        calendar.add(Calendar.DATE, -6);

        // Set the Calendar new date as minimum date of date picker
        dpd.getDatePicker().setMinDate(calendar.getTimeInMillis());

        // So, now date picker selectable date range is 7 days only

        // Return the DatePickerDialog
        return dpd;
    }

    public void onDateSet(DatePicker view, int year, int month, int day) {
        // Do something with the chosen date
        TextView tv = (TextView) getActivity().findViewById(R.id.tv);

        // Create a Date variable/object with user chosen date
        Calendar cal = Calendar.getInstance();
        cal.setTimeInMillis(0);
        cal.set(year, month, day, 0, 0, 0);
        Date chosenDate = cal.getTime();

        // Format the date using style and locale
        DateFormat df = DateFormat.getDateInstance(DateFormat.MEDIUM, Locale.US);
        String formattedDate = df.format(chosenDate);

        // Display the chosen date to app interface
        tv.setText(formattedDate);//formattedDate is the data that I want to pass to myFood.
    }
}

@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
    String text = parent.getItemAtPosition(position).toString();
}

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

}
}

我的应用程序的流程是用户可以选择食物、选择日期(从当前日期起 7 天)和时间列表，然后点击提交。数据库将接收所有数据并保存到 firebase。

Answer 1

我们可以使用 Bundle 将数据从一个 fragment 发送到另一个 fragment

发送 fragment

RecievingFragment fragment = new RecievingFragment ();
Bundle args = new Bundle();
args.putString("Key", "Value");
fragment.setArguments(args);

getFragmentManager().beginTransaction().add(R.id.container, fragment).commit();

接收 fragment

在新 fragment 的onCreateView中:

String value = getArguments().getString("YourKey");