調用選項卡片段來自活動的方法

Question

我正在開發具有兩個選項卡的應用程序。標籤1中的片段記錄音頻，標籤2中的片段顯示文件列表。現在我想每次單擊停止按鈕時都會刷新SwipeRefreshLayout中的列表。我做了一個接口，以便片段1調用活動，現在活動必須調用片段2中的onRefresh()或調用onRefresh()的片段2中的任何其他方法。我沒有那個工作。我不能使用

Fragment fragment=getSupportFragmentManager.findFragmentbyId() 

因爲我沒有在XML中的片段，這意味着沒有ID。
任何幫助？
這裏的代碼：

活動：

public class RecordingActivity extends AppCompatActivity implements Item_recorded{ 

private Toolbar toolbar; 

TabLayout tabLayout; 
PopupWindow mPopupWindow; 
ViewPager pager; 
View pview; 
static Boolean Saved; 


@Override 
protected void onCreate(Bundle savedInstanceState) { 

    Saved= false; 

    ShowList.mp = new MediaPlayer(); 



    super.onCreate(savedInstanceState); 
    if (getSharedPreferences("jdev.voicerecorder", Context.MODE_PRIVATE).getBoolean("navBar", false)==true){ 
     getWindow().setNavigationBarColor(getResources().getColor(R.color.primary)); 
    } 


    setContentView(R.layout.activity_recording); 
    toolbar = (Toolbar) findViewById(R.id.toolbar); 

    TabLayout tabLayout = (TabLayout) findViewById(R.id.tabHost); 
    ViewPager viewPager = (ViewPager) findViewById(R.id.pager); 

    if (toolbar != null) { 
     setSupportActionBar(toolbar); 
    } 

    viewPager.setAdapter(new SectionPagerAdapter(getSupportFragmentManager())); 
    tabLayout.setupWithViewPager(viewPager); 
} 

@Override 
public boolean onCreateOptionsMenu(Menu menu) { 


    getMenuInflater().inflate(R.menu.menu_recording,menu); 
    return true; 
} 

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    super.onOptionsItemSelected(item); 


    if (item.getItemId()==R.id.information){ 
     DialogFragment newFragment = new madeby(); 
     newFragment.show(getSupportFragmentManager(), "missiles"); 
    } 

    if (item.getItemId()==R.id.settings){ 
     Intent intent=new Intent(this, Settings.class); 
     startActivity(intent); 
    } 

    return super.onOptionsItemSelected(item); 







} 


@Override 
protected void onResume() { 
    super.onResume(); 

    if (getSharedPreferences("jdev.voicerecorder", Context.MODE_PRIVATE).getBoolean("navBar", false)==true){ 

     getWindow().setNavigationBarColor(getResources().getColor(R.color.primary)); 

    } 
} 

@Override 
public void recorded() { 
    FragmentManager fragmentManager=getSupportFragmentManager(); 




} 

public class SectionPagerAdapter extends FragmentStatePagerAdapter { 

    public SectionPagerAdapter(FragmentManager fm) { 
     super(fm); 
    } 

    @Override 
    public Fragment getItem(int position) { 
     switch (position) { 
      case 0: 
      default: 


       return new Record(); 
      case 1: 

       return new ShowList(); 
     } 
    } 

    @Override 
    public int getCount() { 
     return 2; 
    } 



    @Override 
    public CharSequence getPageTitle(int position) { 

     String settitle1 = getResources().getString(R.string.recordTab); 
     String settitle2 = getResources().getString(R.string.recordsTab); 


     String tabtitles[] = new String[] { settitle1, settitle2 }; 

     return tabtitles[position]; 
    } 
} 

}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:app="http://schemas.android.com/apk/res-auto" 
xmlns:tools="http://schemas.android.com/tools" 
android:id="@+id/mainlayout" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:orientation="vertical" 
tools:context=".RecordingActivity"> 

<android.support.design.widget.AppBarLayout 
    android:id="@+id/appbar" 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"> 

    <android.support.v7.widget.Toolbar 
     android:id="@+id/toolbar" 
     android:layout_width="match_parent" 
     android:layout_height="?attr/actionBarSize" 
     android:background="?attr/colorPrimary" 
     app:popupTheme="@style/ThemeOverlay.AppCompat.Light" /> 

    <android.support.design.widget.TabLayout 
     android:id="@+id/tabHost" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" /> 

</android.support.design.widget.AppBarLayout> 

<android.support.v4.view.ViewPager 
    android:id="@+id/pager" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:layout_below="@+id/tabHost" /> 

片段2：

public class ShowList extends ListFragment implements SwipeRefreshLayout.OnRefreshListener, MediaPlayer.OnPreparedListener{ 
private String path; 
static SwipeRefreshLayout mSwipeLayout; 
private ArrayAdapter<String> adapter; 
private ArrayList<String> values; 
private String[] list; 
private TextView durationT; 
private String path2; 
private String path3; 
private File dir3; 
private File dir2; 
private File dir; 
private View p; 
private int length; 
static MediaPlayer mp; 
private long currentNow; 
static boolean isPlaying; 
SeekBar mSeekBar; 
int duration; 
static TextView mTime; 
ArrayList<String> mdurationlist; 
MediaPlayer mp1; 
String durations; 
static CardView cw; 
int cx; 
int cy; 
int initialRadius; 
Animator anim; 
boolean cardOutforplay; 
boolean forRRunnable; 



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


@Override 
public View onCreateView(LayoutInflater inflater, final ViewGroup container, 
         Bundle savedInstanceState) { 
    // Inflate the layout for this fragment 
    p= inflater.inflate(R.layout.fragment_show_list, container, false); 
    mTime=(TextView)p.findViewById(R.id.playerTime); 
    mTime.setText("00:00/00:00"); 

    mSeekBar=(SeekBar)p.findViewById(R.id.progressbar); 
    mSeekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() { 
     @Override 
     public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { 
      if (fromUser){ 
       mp.seekTo(progress); 
      } 
     } 

     @Override 
     public void onStartTrackingTouch(SeekBar seekBar) { 

     } 

     @Override 
     public void onStopTrackingTouch(SeekBar seekBar) { 

     } 
    }); 
    mSwipeLayout=(SwipeRefreshLayout)p.findViewById(R.id.swipelayout); 
    mSwipeLayout.setOnRefreshListener(this); 

    mSwipeLayout.setColorSchemeResources(R.color.accent); 

    cw=(CardView)p.findViewById(R.id.progresscard); 
    cw.setVisibility(View.INVISIBLE); 

    // Use the current directory as title 
    path = Environment.getExternalStorageDirectory() 
      +File.separator 
      +"Recorded" 
      +File.separator; 
    if (getActivity().getIntent().hasExtra("path")) { 
     path = getActivity().getIntent().getStringExtra("path"); 
    } 

    // Read all files sorted into the values-array 

    values = new ArrayList<String>(); 

    dir = new File(path); 
    list = dir.list(); 
    if (list != null) { 
     for (String file : list) { 
      if (file.endsWith(".wav")){ 
       values.add(file); 
      } 
      else if (file.endsWith(".3gp")){ 
       values.add(file); 
      } 
     } 
    } 
    Collections.sort(values); 


    // Put the data into the list 
    adapter = new ArrayAdapter<String>(getActivity(), 
      R.layout.recording_list_item,R.id.listText, values); 
    setListAdapter(adapter); 

    Thread t = new Thread() { 

     @Override 
     public void run() { 
      try { 
       while (!isInterrupted()) { 
        Thread.sleep(1); 
        getActivity().runOnUiThread(new Runnable() { 
         @Override 
         public void run() { 
          if (RecordingActivity.Saved==true){ 
           onRefresh(); 
           interrupt(); 
           RecordingActivity.Saved=false; 
          } 
          if (!RecordingActivity.Saved){ 
           CountDownTimer countDownTimer=new CountDownTimer(300,1000) { 
            @Override 
            public void onTick(long millisUntilFinished) { 

            } 

            @Override 
            public void onFinish() { 
             interrupt(); 

            } 
           }.start(); 

          } 
         } 
        }); 
       } 
      } catch (InterruptedException e) { 
      } 
     } 
    }; 

    t.start(); 
    return p; 
} 






@Override 
public void onActivityCreated(Bundle savedInstanceState){ 
    super.onActivityCreated(savedInstanceState); 

    getListView().setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() { 
     @Override 
     public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) { 
      View myView = p.findViewById(R.id.progresscard); 
      if (myView.getVisibility()==View.VISIBLE){ 
       myView.setVisibility(View.INVISIBLE); 
      } 

      path3 = Environment.getExternalStorageDirectory() 
        + File.separator 
        + "Recorded" 
        + File.separator; 
      dir3 = new File(path3); 
      list = dir3.list(); 


      File selected = new File(path + values.get(position)); 
      selected.delete(); 
      adapter.notifyDataSetChanged(); 
      onRefresh(); 
      Toast.makeText(getActivity().getApplicationContext(), R.string.deleted, Toast.LENGTH_SHORT).show(); 

      if (myView.getVisibility()==View.VISIBLE){ 
       myView.setVisibility(View.INVISIBLE); 
      } 



      return false; 
     } 
    }); 
} 

@Override 
public void onListItemClick(ListView l, View v, final int position, long id) { 
    forRRunnable= false; 


    View myView= p.findViewById(R.id.progresscard); 

    mp=new MediaPlayer(); 

    Log.v("mp.isPlaying()", "mp.isPlaying==" +mp.isPlaying()); 

    mSeekBar.setProgress(0); 
    cardOutforplay= false; 

    if (Build.VERSION.SDK_INT>= Build.VERSION_CODES.LOLLIPOP) { 
     if (!isPlaying){ 


      // previously invisible view 


      int cx = myView.getMeasuredWidth()/2; 
      int cy = myView.getMeasuredHeight()/2; 

      // get the final radius for the clipping circle 
      int finalRadius = Math.max(myView.getWidth(), myView.getHeight())/2; 
      Animator anim = ViewAnimationUtils.createCircularReveal(myView, cx, cy, 0, finalRadius); 
      myView.setVisibility(View.VISIBLE); 
      anim.start(); 
     } 

} 
    if (Build.VERSION.SDK_INT< Build.VERSION_CODES.LOLLIPOP){ 
     if (!isPlaying){ 
       myView.setVisibility(View.VISIBLE); 
     } 
    } 
    if (isPlaying){ 
     cardOutforplay = true; 
     mp.stop(); 
     mp.release(); 
    } 

    String musicURI = path 
      + values.get(position); 

    try { 
     mp.setDataSource(musicURI); 
    } catch (IOException | IllegalStateException e) { 
     e.printStackTrace(); 
    } 
    try { 
     mp.prepare(); 
    } catch (IOException | IllegalStateException e) { 
     e.printStackTrace(); 
    } 
    mp.setOnPreparedListener(this); 
    mp.setOnCompletionListener(new MediaPlayer.OnCompletionListener() { 
     @Override 
     public void onCompletion(MediaPlayer mp) { 
      final View myView = p.findViewById(R.id.progresscard); 
      isPlaying=false; 


      mTime.setText("00:00/00:00"); 


      if (!cardOutforplay) { 
       if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { 
        // get the center for the clipping circle 
        cx = myView.getMeasuredWidth()/2; 
        cy = myView.getMeasuredHeight()/2; 

        initialRadius = myView.getWidth(); 

        anim = 
          ViewAnimationUtils.createCircularReveal(myView, cx, cy, initialRadius, 0); 

        anim.addListener(new AnimatorListenerAdapter() { 
         @Override 
         public void onAnimationEnd(Animator animation) { 

          super.onAnimationEnd(animation); 

          myView.setVisibility(View.INVISIBLE); 
          mSeekBar.setProgress(0); 
         } 
        }); 


        anim.start(); 
       } 
       if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) { 
        Toast.makeText(getActivity(), "Visibility is: " + myView.getVisibility(), Toast.LENGTH_SHORT).show(); 

        myView.setVisibility(View.INVISIBLE); 
        mSeekBar.setProgress(0); 
       } 

      } 
     } 
    }); 
} 



private Runnable onEverySecond=new Runnable() { 
    @Override 
    public void run() { 
     if (forRRunnable){ 
      if (mSeekBar!=null){ 
       if (mp.isPlaying()){ 
        mSeekBar.setProgress(mp.getCurrentPosition()); 
       } 

      } 
      if (mp.isPlaying()){ 
       mSeekBar.postDelayed(onEverySecond,1000); 
       updateTime(); 
      } 
     } 


    } 
}; 


@Override 
public void onRefresh() { 
    path2 = Environment.getExternalStorageDirectory() 
      + File.separator 
      + "Recorded" 
      + File.separator; 
    dir2=new File(path2); 
    values.clear(); 
    adapter.notifyDataSetChanged(); 
    list=dir2.list(); 

    for (String file:list){ 
     if (file.endsWith(".wav")){ 
      values.add(file); 
      adapter.notifyDataSetChanged(); 
     } 
     else if (file.endsWith(".3gp")){ 
      values.add(file); 
      adapter.notifyDataSetChanged(); 
     } 
    } 
    Collections.sort(values); 

    mSwipeLayout.setRefreshing(false); 

} 

@Override 
public void onPrepared(MediaPlayer mp) { 
    duration = mp.getDuration(); 
    mSeekBar.setMax(duration); 

    mp.setVolume(1.0f, 1.0f); 



    mp.start(); 

    if (mp.isPlaying()){ 
     forRRunnable=true; 
     mSeekBar.setProgress(0); 
     isPlaying = true; 
     mSeekBar.postDelayed(onEverySecond, 1000); 

    } 
} 


private void updateTime(){ 
    do { 
     int current = mp.getCurrentPosition(); 
     int dSeconds = (int) (duration/1000) % 60 ; 
     int dMinutes = (int) ((duration/(1000*60)) % 60); 
     int dHours = (int) ((duration/(1000*60*60)) % 24); 

     int cSeconds = (int) (current/1000) % 60 ; 
     int cMinutes = (int) ((current/(1000*60)) % 60); 
     int cHours = (int) ((current/(1000*60*60)) % 24); 

     if(dHours == 0){ 
      mTime.setText(String.format("%02d:%02d/%02d:%02d", cMinutes, cSeconds, dMinutes, dSeconds)); 
     }else{ 
      mTime.setText(String.format("%02d:%02d:%02d/%02d:%02d:%02d", cHours, cMinutes, cSeconds, dHours, dMinutes, dSeconds)); 
     } 

     try{ 
      Log.d("Value: ", String.valueOf((int) (current * 100/duration))); 
      if(mSeekBar.getProgress() >= 100){ 
       break; 
      } 
     }catch (Exception e) {} 
    }while (mSeekBar.getProgress() <= 100); 
} 

public void answer(String answer){ 
    getActivity().getWindow().setNavigationBarColor(R.color.primary); 
    onRefresh(); 
} 

}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:tools="http://schemas.android.com/tools" 
xmlns:card_view="http://schemas.android.com/apk/res-auto" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:background="@color/white" 
tools:context="jdev.voicerecorder.ShowList" 
android:id="@+id/fragmentshowlistlayout"> 

<android.support.v4.widget.SwipeRefreshLayout 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:id="@+id/swipelayout" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent"> 

    <ListView 
     android:id="@android:id/list" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" /> 

</android.support.v4.widget.SwipeRefreshLayout> 



    <android.support.v7.widget.CardView 
     android:id="@+id/progresscard" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:layout_marginLeft="8dp" 
     android:layout_marginRight="8dp" 
     android:layout_marginBottom="8dp" 
     android:visibility="invisible" 
     android:layout_alignParentBottom="true"> 

     <RelativeLayout 
      android:layout_width="match_parent" 
      android:layout_height="64dp"> 

      <SeekBar 
       android:layout_width="match_parent" 
       android:layout_height="wrap_content" 
       android:layout_weight="0.5" 
       android:id="@+id/progressbar" 
       android:layout_alignParentTop="true" 
       android:layout_centerHorizontal="true" 
       android:paddingRight="16dp" 
       android:paddingLeft="16dp" 
       android:paddingTop="4dp" /> 

      <TextView 
       android:layout_width="match_parent" 
       android:layout_height="wrap_content" 
       android:layout_weight="0.5" 
       android:textSize="16dp" 
       android:id="@+id/playerTime" 
       android:fontFamily="sans-serif-light" 
       android:layout_gravity="right" 
       android:layout_below="@+id/progressbar" 
       android:layout_alignParentRight="true" 
       android:layout_alignParentEnd="true" 
       android:gravity="right" 
       android:text="00:00/00:00" 
       android:paddingRight="16dp" /> 


     </RelativeLayout> 
    </android.support.v7.widget.CardView> 

Answer 1

請仔細研究：fragments communication

基本上，你的情況，店片段的引用爲您Activity的一部分。因此，您將有RecordFragment mRecordFragment和ShowListFragment mShowListFragment作爲類成員，如果您需要刷新任何內容 - 只需在片段中創建一個方法並直接調用它即可。

簡單的例子：
活動

public void recorder() { 
    mShowListFragment.onRefresh(); 
}