fragment之间的数据传递

Posted 2020-10-10

 

  之前在实现activity之间基于fragment的activity之间的数据传递，现在要实现同一个activity间托管的两个fragment的数据间的传递。

我们要实现这两个数据的传递需要新建一个方法，将其作为argument传给fragment。

 1. DatePickerFragment

package edu.niit.android.criminalintent;


import android.app.Activity;
import android.app.Dialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.DialogFragment;
import android.app.AlertDialog;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.DatePicker;

import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

/**
 * Created by Administrator on 2017/9/25 0025.
 */

public class DatePickerFragment extends DialogFragment {
    public static final String EXTRA_DATE=
            "edu.niit.android.criminalintent.date";
    private static  final String ARG_DATE = "date";
    private DatePicker mDatePicker;
    public static  DatePickerFragment newInstance(Date date){
        Bundle args = new Bundle();
        args.putSerializable(ARG_DATE,date);
        DatePickerFragment fragment = new DatePickerFragment();
        fragment.setArguments(args);
        return fragment;//新建的方法
    }
    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState){
      //获取Date对象并初始化DatePicker
        Date date = (Date) getArguments().getSerializable(ARG_DATE);
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        int year = calendar.get(Calendar.YEAR);
        int month = calendar.get(Calendar.MONTH);
        int day= calendar.get(Calendar.DAY_OF_MONTH);
         //添加DatePicker
        View v = LayoutInflater.from(getActivity())
                .inflate(R.layout.dialog_date, null);
     mDatePicker = (DatePicker) v.findViewById(R.id.dialog_date_picker);
        mDatePicker.init(year,month,day,null);
        return new AlertDialog.Builder(getActivity())
                .setView(v)
                .setTitle(R.string.date_picker_title)
                .setPositiveButton(android.R.string.ok,
                        new DialogInterface.OnClickListener(){
                            @Override
                            public void onClick(DialogInterface dialog, int which){
                                int year = mDatePicker.getYear();
                                int month = mDatePicker.getMonth();
                                int day = mDatePicker.getDayOfMonth();
                                Date date = new GregorianCalendar(year,month,day).getTime();
                                sendResult(Activity.RESULT_OK,date);
                            }
                        })
                .create();
    }
//回调目标fragment
private void sendResult(int resultCode, Date date){
    if(getTargetFragment()==null){
        return;
    }
    Intent intent = new Intent();
    intent.putExtra(EXTRA_DATE,date);
    getTargetFragment()
            .onActivityResult(getTargetRequestCode(),resultCode,intent);
}
}

CrimeFragment

package edu.niit.android.criminalintent;


import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.provider.MediaStore;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.content.FileProvider;
import android.text.Editable;
import android.text.TextWatcher;
import android.text.format.DateFormat;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.ImageView;

import java.io.File;
import java.util.Date;
import java.util.List;
import java.util.UUID;

/**
 * Created by Administrator on 2017/9/11 0011.
 */

public class CrimeFragment extends Fragment {
    private static final String ARG_CRIME_ID="crime_id";
    private static final String DIALOG_DATE="DialogDate";
    private static final int REQUEST_DATE=0;//设置目标fragment
    private static final int REQUEST_CONTACT=1;
    private static final int REQUEST_PHOTO=2;
    private Crime mCrime;
    private File mPhotoFile;
    private EditText mTitleField;
    private Button mDataButton;
    private CheckBox mSolvedCheckBox;
    private Button mReportButton;
    private Button mSuspectButton;
    private ImageButton mPhotoButton;
    private ImageView mPhotoView;
    public static CrimeFragment newInstance(UUID crimeId){
        Bundle args = new Bundle();
        args.putSerializable(ARG_CRIME_ID,crimeId);
        CrimeFragment fragment = new CrimeFragment();
        fragment.setArguments(args);
        return fragment;
    }
    @Override
    public void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        UUID crimeId = (UUID) getArguments().getSerializable(ARG_CRIME_ID);
        mCrime = CrimeLab.get(getActivity()).getCrime(crimeId);
        mPhotoFile = CrimeLab.get(getActivity()).getPhotoFile(mCrime);
    }
    @Override
    public void onPause(){
        super.onPause();
        CrimeLab.get(getActivity())
        .updateCrime(mCrime);
    }
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState){
        View v = inflater.inflate(R.layout.fragment_crime, container, false);
        mTitleField = (EditText)v.findViewById(R.id.crime_title);
        mTitleField.setText(mCrime.getTitle());
        mTitleField.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

            }

            @Override
            public void afterTextChanged(Editable s) {

            }
        });
        mDataButton=(Button)v.findViewById(R.id.crime_data);
        mDataButton.setText(mCrime.getDate().toString());
        mDataButton.setOnClickListener(new  View.OnClickListener(){
            @Override
            public void onClick(View v){
                FragmentManager manager = getFragmentManager();
                DatePickerFragment dialog = DatePickerFragment
                        .newInstance(mCrime.getDate());//添加方法
                dialog.setTargetFragment(CrimeFragment.this,REQUEST_DATE);
                dialog.show(manager, DIALOG_DATE);
            }
                                       });
        mSolvedCheckBox = (CheckBox)v.findViewById(R.id.crime_solved);
        mSolvedCheckBox.setChecked(mCrime.isSolved());
        mSolvedCheckBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                mCrime.setSolved(isChecked);
            }
        });
        mReportButton=(Button) v.findViewById(R.id.crime_report);
        mReportButton.setOnClickListener(new View.OnClickListener(){
            public  void onClick(View v){
                Intent i=new Intent(Intent.ACTION_SEND);
                i.setType("text/plain");
                i.putExtra(Intent.EXTRA_TEXT,getCrimeReport());
                i.putExtra(Intent.EXTRA_SUBJECT,
                        getString(R.string.crime_report_subject));
                i=Intent.createChooser(i,getString(R.string.send_report));
                startActivity(i);
            }
        });
        final Intent pickContact = new Intent(Intent.ACTION_PICK,
                ContactsContract.Contacts.CONTENT_URI);
        mSuspectButton=(Button) v.findViewById(R.id.crime_suspect);
        mSuspectButton.setOnClickListener(new View.OnClickListener(){
            public void onClick(View v){
                startActivityForResult(pickContact,REQUEST_CONTACT);
            }
        });

        if (mCrime.getSuspect()!=null){
            mSuspectButton.setText(mCrime.getSuspect());
        }
        PackageManager packageManager = getActivity().getPackageManager();
        if (packageManager.resolveActivity(pickContact,
                PackageManager.MATCH_DEFAULT_ONLY)==null){
            mSuspectButton.setEnabled(false);
        }
        mPhotoButton=(ImageButton) v.findViewById(R.id.crime_camera);
        final Intent captureImage = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        boolean canTakePhoto = mPhotoFile !=null&&captureImage.resolveActivity(packageManager)!=null;
        mPhotoButton.setEnabled(canTakePhoto);
        mPhotoButton.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v){
                Uri uri = FileProvider.getUriForFile(getActivity(),
                        "edu.niit.android.criminalintent.fileprovider",mPhotoFile);
                captureImage.putExtra(MediaStore.EXTRA_OUTPUT,uri);
                List<ResolveInfo> cameraActivities=getActivity()
                        .getPackageManager().queryIntentActivities(captureImage,
                                PackageManager.MATCH_DEFAULT_ONLY);
                for (ResolveInfo activity : cameraActivities){
                    getActivity().grantUriPermission(activity.activityInfo.packageName,
                            uri,Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
                }
                startActivityForResult(captureImage,REQUEST_PHOTO);
            }
        });
        mPhotoView=(ImageView) v.findViewById(R.id.crime_photo);
        return v;
    }
   @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data){
       if (resultCode!=Activity.RESULT_OK){
           return;
       }
       if (requestCode==REQUEST_DATE){
           Date date = (Date) data
                   .getSerializableExtra(DatePickerFragment.EXTRA_DATE);
           mCrime.setDate(date);
           updateDate();//使用updateDate私有方法
       }else if(requestCode==REQUEST_CONTACT&& data !=null){
           Uri contactUri = data.getData();
           String[] queryFields = new String[]{
                   ContactsContract.Contacts.DISPLAY_NAME
           };
           Cursor c = getActivity().getContentResolver()
                   .query(contactUri,queryFields,null,null,null);
           try {
               if (c.getCount()==0){
                   return;
               }
               c.moveToFirst();
               String suspect = c.getString(0);
               mCrime.setSuspect(suspect);
               mSuspectButton.setText(suspect);
           }finally {
               c.close();
           }
       }
   }

    private void updateDate() {
        mDataButton.setText(mCrime.getDate().toString());//高亮选取日期按钮更新代码
    }//相应DatePicker对话框

    private String getCrimeReport(){
        String solvedString =null;
        if(mCrime.isSolved()){
            solvedString= getString(R.string.crime_report_solved);
        }else {
            solvedString=getString(R.string.crime_report_unsolved);
        }
        String dateFormat = "EEE, MMM dd";
        String dateString = DateFormat.format(dateFormat,mCrime.getDate()).toString();
        String suspect = mCrime.getSuspect();
        if (suspect==null){
            suspect = getString(R.string.crime_report_no_suspect);
        }else {
            suspect=getString(R.string.crime_report_suspect,suspect);
        }

        String report = getString(R.string.crime_report,
                mCrime.getTitle(), dateString, solvedString,suspect);
        return report;
    }
}

SingleFragmentActivity

public abstract class SingleFragmentActivity extends AppCompatActivity{
    protected abstract Fragment createFragment();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fragment);
        FragmentManager fm = getSupportFragmentManager();
        Fragment fragment = fm.findFragmentById(R.id.fragment_container);
        if(fragment == null){
            fragment = new CrimeFragment();
            fm.beginTransaction()
                    .add(R.id.fragment_container, fragment)
                    .commit();

        }
    }
}

运行结果