Android中切换标签片段之间的滞后

Question

我遇到了一个问题，即每当我在不同标签之间切换时，过程都会滞后一两秒钟。我怎样才能消除这种滞后？在片段的创建功能中没有这样的东西。我在这里发布代码。

这是正在调用该片段Dashboardnew活动代码：

private void setupDrawerContent(final NavigationView navigationView) { 
    //revision: this don't works, use setOnChildClickListener() and setOnGroupClickListener() above instead 
    expandableList.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() { 
     @Override 
     public boolean onGroupClick(ExpandableListView expandableListView, View view, int i, long l) { 
      if(i==0) { 
       //Toast.makeText(getApplicationContext(),"View Tasks",Toast.LENGTH_LONG).show(); 
       fab.setVisibility(View.VISIBLE); 
       if (filterApplied) { 
        persistentbottomSheet.setVisibility(View.VISIBLE); 
        persistentbottomSheet.bringToFront(); 
        fab.bringToFront(); 
       } 
       fragment = new DashboardNew(); 
       if (fragment != null) { 
        manager.beginTransaction().replace(R.id.dashboard_frame, fragment).commit(); 
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout); 
        drawer.closeDrawer(GravityCompat.START); 
       } 
       /* new Handler().postDelayed(new Runnable() { 
        @Override 
        public void run() { 
         if (fragment != null) { 
          manager.beginTransaction() 
            .replace(R.id.dashboard_frame, fragment) 
            .commit(); 

         } 
        } 
       }, 300);*/ 
       //drawer.closeDrawer(GravityCompat.START); 
      } 

      if(i==1) { 

      } 

      if(i==2) { 
       prefs.edit().remove("firstTime").apply(); 
       Intent intent = new Intent(getApplication(), Login.class) 
         .setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
       finish(); 
       intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); 
       intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK); 
       startActivity(intent); 
      } 

      return false; 
     } 
    }); 

    expandableList.setOnChildClickListener(new ExpandableListView.OnChildClickListener() { 
     @Override 
     public boolean onChildClick(ExpandableListView expandableListView, View view, int groupPosition, int childPosition, long l) { 
      if (groupPosition == 1 && childPosition == 0) { 
       fabvisibility = false; 
       //so this code only executes if the 2nd child in the 2nd group is clicked 
       fragment=new AddUser(); 
       if (fragment != null) { 
        manager.beginTransaction() 
          .replace(R.id.dashboard_frame, fragment,"AddUser") 
          //.add(fragment,"AddUser") 
          // .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN) 
          .commit(); 
       } 
       drawer.closeDrawer(GravityCompat.START); 
      } 

      if (groupPosition == 1 && childPosition == 1) { 
       //so this code only executes if the 2nd child in the 2nd group is clicked 
       fabvisibility = false; 
       fragment=new ViewUsers(); 
       if (fragment != null) { 
        manager.beginTransaction() 
          .replace(R.id.dashboard_frame, fragment) 
          .commit(); 
        drawer.closeDrawer(GravityCompat.START); 
       } 
      } 

      return false; 
     } 
    }); 
} 

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    // Handle action bar item clicks here. The action bar will 
    // automatically handle clicks on the Home/Up button, so long 
    // as you specify a parent activity in AndroidManifest.xml. 
    switch (item.getItemId()) { 
     case android.R.id.home: 
      drawer.openDrawer(GravityCompat.START); 
      return true; 
    } 

    return super.onOptionsItemSelected(item); 
} 
} 

为Dashboardnew片段的代码是：

initialize(rootview); 
    clicklisteners(); 
    createViewPager(viewPager); 
    tabLayout.setupWithViewPager(viewPager); 
    createTabIcons(); 

    return rootview; 
} 

private void clicklisteners() 
{ 
    usualTasks.setOnClickListener(this); 
} 
@Override 
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { 
    super.onViewCreated(view, savedInstanceState); 
    //you can set the title for your toolbar here for different fragments different titles 
    getActivity().setTitle("The Checklist"); 
} 
@Override 
public void onClick(View v) { 
    switch (v.getId()) { 
     case R.id.toggleButton: { 

      if(usualTasks.isChecked()) { 
       Toast.makeText(getActivity(), "Toggle button is on", Toast.LENGTH_LONG).show(); 
       showRoleDialog(); 
       FragmentTransaction trans = getFragmentManager().beginTransaction(); 
       trans.replace(R.id.base_pending, new UsualTasks()); 

       WelcomeActivity.persistentbottomSheet.setVisibility(View.INVISIBLE); 
       //WelcomeActivity.fab.setVisibility(View.INVISIBLE); 

       trans.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN); 
       trans.commit(); 
      } 
      else { 
       Toast.makeText(getActivity(), "Toggle button is Off", Toast.LENGTH_LONG).show(); 
       FragmentTransaction trans = getFragmentManager().beginTransaction(); 
       trans.replace(R.id.usual_pending, new PendingTasks()); 
       trans.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN); 
       if (WelcomeActivity.filterApplied == true) { 
        WelcomeActivity.persistentbottomSheet.setVisibility(View.VISIBLE); 
        WelcomeActivity.persistentbottomSheet.bringToFront(); 
        WelcomeActivity.fab.setVisibility(View.VISIBLE); 

       } 
       if(UsualTasks.shown) { 
        UsualTasks.mSnackBar.dismiss(); 
       } 

       trans.commit(); 
      } 
     } 
    } 
} 

public void populateList(HashMap<Integer, String> myMap, List myList){ 
    Set<Map.Entry<Integer, String>> setMap = myMap.entrySet(); 
    Iterator<Map.Entry<Integer, String>> iteratorMap = setMap.iterator(); 
    int item=0; 
    while(iteratorMap.hasNext()) { 
     Map.Entry<Integer, String> entry = (Map.Entry<Integer, String>) iteratorMap.next(); 
     myList.add(entry.getValue()); 
     item++; 
    } 
} 

private void showRoleDialog() { 
    final Dialog dialog = new Dialog(getContext()); 
    dialog.requestWindowFeature(Window.FEATURE_NO_TITLE); 
    dialog.setContentView(R.layout.usualtask_dialog); 
    rolelist = new ArrayList<Map<Integer,String>>(); 
    roles= new HashMap<Integer, String>(); 

    roles.put(1, "Senior Manager"); 
    roles.put(2, "Admin"); 
    roles.put(3, "HR"); 
    populateList(roles,rolelist); 

    ArrayAdapter arrayAdapter = new ArrayAdapter<String>(getContext(), android.R.layout.simple_list_item_single_choice, rolelist) 
    { 
     @Override 
     public View getView(int position, View convertView, ViewGroup parent){ 
      // Get the current item from ListView 
      View view = super.getView(position,convertView,parent); 
      TextView tv = (TextView) view.findViewById(android.R.id.text1); 
      tv.setTextColor(Color.parseColor("#353b41")); 
      return view; 

     } 
    }; 
    dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT)); 

    selectRole= (ListView)dialog.findViewById(R.id.selectrole); 
    submitRole= (Button)dialog.findViewById(R.id.btsubmitrole); 
    selectRole.setChoiceMode(ListView.CHOICE_MODE_SINGLE); 
    selectRole.setAdapter(arrayAdapter); 

    selectRole.setOnItemClickListener(new AdapterView.OnItemClickListener() { 
     @Override 
     public void onItemClick(AdapterView<?> parent, View view, int position, long id) {} 
    }); 

    submitRole.setOnClickListener(new View.OnClickListener(){ 

     @Override 
     public void onClick(View view) { 
      dialog.dismiss(); 
     } 
    }); 

    dialog.show(); 
} 

private void createTabIcons() { 
    RelativeLayout tabOne = (RelativeLayout) LayoutInflater.from(getContext()).inflate(R.layout.pending_tab, null); 
    TextView textTab=(TextView)tabOne.findViewById(R.id.tab); 
    ImageView imageTab=(ImageView) tabOne.findViewById(R.id.notifyimage); 

    //TextDrawable drawable = TextDrawable.builder().buildRound("999",Color.RED); // radius in px 
    TextDrawable drawable = TextDrawable.builder() 
      .buildRoundRect("999",Color.RED,18); // radius in px 
    imageTab.setImageDrawable(drawable); 
    textTab.setText("Pending"); 
    tabLayout.getTabAt(1).setCustomView(tabOne); 

    RelativeLayout tabTwo = (RelativeLayout) LayoutInflater.from(getContext()).inflate(R.layout.completed_tab, null); 
    TextView textTab1=(TextView)tabTwo.findViewById(R.id.pending_tab); 
    textTab1.setText("Completed"); 
    tabLayout.getTabAt(0).setCustomView(tabTwo); 
} 

private void initialize(View rootview) { 
    toolbar = (Toolbar)rootview.findViewById(R.id.toolbar); 
    viewPager = (ViewPager)rootview.findViewById(R.id.viewpager); 
    tabLayout = (TabLayout)rootview.findViewById(R.id.tabs); 
    usualTasks=(ToggleButton)rootview.findViewById(R.id.toggleButton); 
} 

private void createViewPager(ViewPager viewPager) { 
     adapter = new DashboardNew.ViewPagerAdapter(getChildFragmentManager()); 
     adapter.addFrag(new CompletedTasks(), "Completed"); 
     adapter.addFrag(new PendingTasks(), "Pending"); 
     viewPager.setAdapter(adapter); 
} 

class ViewPagerAdapter extends FragmentPagerAdapter { 
    private final List<Fragment> mFragmentList = new ArrayList<>(); 
    private final List<String> mFragmentTitleList = new ArrayList<>(); 
    public ViewPagerAdapter(FragmentManager manager) { 
     super(manager); 
    } 

    @Override 
    public Fragment getItem(int position) { 
     if (position == 0) 
      return new CompletedTasks(); 
     else 
      return new PendingTasks(); 
    } 

    @Override 
    public int getCount() { 
     return mFragmentList.size(); 
    } 

    public void addFrag(Fragment fragment, String title) { 
     mFragmentList.add(fragment); 
     mFragmentTitleList.add(title); 
    } 

    @Override 
    public CharSequence getPageTitle(int position) { 
     return mFragmentTitleList.get(position); 
    } 
} 
} 

，这里是为完成任务的代码：

completedTaskList = (ListView) rootview.findViewById(R.id.completedlist); 
    BaseMenuActivity.filterState=false; 

    if(UsualTasks.shown) { 
     UsualTasks.mSnackBar.dismiss(); 
    } 

    generateListdata(); 

    return rootview; 
} 

private void generateListdata() { 
    completedTasks.add(new completedTasks("Call the Owner","Wembley GP","Daily",R.drawable.completed_tick,R.drawable.access_dashboard)); 
    completedTasks.add(new completedTasks("Check the safety of patients","Wembley GP","Daily",R.drawable.completed_tick,R.drawable.safety_dashboard)); 
    completedTasks.add(new completedTasks("Admin needs to do specific task","Wembley GP","Daily",R.drawable.completed_tick,R.drawable.admin_dashboard)); 
    completedTasks.add(new completedTasks("Get the specific work done","Wembley GP","Daily",R.drawable.completed_tick,R.drawable.access_dashboard)); 
    completedTasks.add(new completedTasks("Need to hire more resources","Wembley GP","Daily",R.drawable.completed_tick,R.drawable.hr_dashboard)); 
    completedTasks.add(new completedTasks("How are patients behaving?","Wembley GP","Daily",R.drawable.completed_tick,R.drawable.patient_experience_dashboard)); 
    completedTasks.add(new completedTasks("Need to adjust the audit report","Wembley GP","Daily",R.drawable.completed_tick,R.drawable.finance_dashboard)); 

    //getListView().setDividerHeight(10); 
    ArrayAdapter<com.example.attech.checklist_attech.Model.completedTasks> adapter = new CompletedTaskAdapter(getContext(), 0,completedTasks); 
    completedTaskList.setAdapter(adapter); 

    completedTaskList.setOnItemClickListener(new android.widget.AdapterView.OnItemClickListener() { 
     public void onItemClick(AdapterView<?> parent, View view, 
           int position, long id) { 
      if (position == 0) {} 

      if (position == 1) {} 

      if (position == 2) { 
       //Intent myIntent = new Intent(view.getContext(), ViewUser.class); 
       //startActivityForResult(myIntent, 0); 
      } 
     } 
    }); 
} 


} 

这是挂起任务的代码：

0所有的

initialize(rootview); 
     generateListdataAssigned(); 
     generateListdata(); 
     generateselectall(); 
     clickListeners(); 

     return rootview; 
    } 

    private void clickListeners() { 
     assignTask.setOnClickListener(this); 
     assignTaskbottom.setOnClickListener(this); 
    } 

    private void populateList(HashMap<Integer, String> myMap, List myList){ 
     Set<Map.Entry<Integer, String>> setMap = myMap.entrySet(); 
     Iterator<Map.Entry<Integer, String>> iteratorMap = setMap.iterator(); 
     int item=0; 
     while(iteratorMap.hasNext()) { 
      Map.Entry<Integer, String> entry = (Map.Entry<Integer, String>) iteratorMap.next(); 
      myList.add(entry.getValue()); 
      item++; 
     } 
    } 


    @Override 
    public void onClick(View v) { 
     switch (v.getId()) { 
      case R.id.assignTaskPending: { 
       selected = !selected; 

       if (selected) { 
        Toast.makeText(getActivity(), "Assigned", Toast.LENGTH_LONG).show(); 
        assignTask.setBackgroundResource(R.color.dark_grey); 
        Toast.makeText(getActivity(),""+WelcomeActivity.filterApplied,Toast.LENGTH_LONG).show(); 
        pendingTaskListAssigned.setVisibility(View.VISIBLE); 
        WelcomeActivity.persistentbottomSheet.setVisibility(View.INVISIBLE); 
        selectAllListView.setVisibility(View.VISIBLE); 
        assignTaskbottom.setVisibility(View.VISIBLE); 
        pendingTaskList.setVisibility(View.INVISIBLE); 

       } 
       else { 
        Toast.makeText(getActivity(), "Clicked", Toast.LENGTH_LONG).show(); 
        Toast.makeText(getActivity(),""+WelcomeActivity.filterApplied,Toast.LENGTH_LONG).show(); 
        pendingTaskListAssigned.setVisibility(View.INVISIBLE); 
        assignTaskbottom.setVisibility(View.INVISIBLE); 
        selectAllListView.setVisibility(View.INVISIBLE); 
        assignTask.setBackgroundResource(R.drawable.box_grey); 
        pendingTaskList.setVisibility(View.VISIBLE); 
        if (WelcomeActivity.filterApplied) { 
         WelcomeActivity.persistentbottomSheet.setVisibility(View.VISIBLE); 
         WelcomeActivity.persistentbottomSheet.bringToFront(); 
         WelcomeActivity.fab.setVisibility(View.VISIBLE); 

        } 
       } 

       break; 
      } 

      case R.id.btassignTask: { 
       showAssignTaskDialog(); 
       break; 
      } 
     } 
    } 

    private void initialize(View rootview) { 
     pendingTaskList = (ListView) rootview.findViewById(R.id.pendinglist); 
     pendingTaskListAssigned = (ListView) rootview.findViewById(R.id.pendinglistassigned); 
     assignTask = (Button) rootview.findViewById(R.id.assignTaskPending); 
     assignTaskbottom = (Button) rootview.findViewById(R.id.btassignTask); 
     selectAllListView= (ListView)rootview.findViewById(R.id.selectalllist); 
    } 

    private void generateListdataAssigned() { 
     pendingTasksAssigned.add(new pendingTasks("System Tasks","Wembley GP","Daily",R.drawable.pending_clock_icon, R.drawable.safety_dashboard)); 
     pendingTasksAssigned.add(new pendingTasks("Call answer speed","Wembley GP","Daily",R.drawable.pending_clock_icon, R.drawable.access_dashboard)); 
     pendingTasksAssigned.add(new pendingTasks("Appointment reasons","Wembley GP","Daily",R.drawable.pending_clock_icon, R.drawable.access_dashboard)); 
     pendingTasksAssigned.add(new pendingTasks("Admin needs to do specific task","Wembley GP","Daily",R.drawable.pending_clock_icon, R.drawable.hr_dashboard)); 

     ArrayAdapter<pendingTasks> adapter = new PendingAssignedAdapter(getContext(), 0, pendingTasksAssigned); 
     pendingTaskListAssigned.setAdapter(adapter); 
     pendingTaskListAssigned.setOnItemClickListener(new android.widget.AdapterView.OnItemClickListener() { 
      public void onItemClick(AdapterView<?> parent, View view, 
            int position, long id) { 
       CheckBox checkBox=(CheckBox)view.findViewById(R.id.checkboxassigned); 
       checkBox.performClick(); 

       if(checkBox.isChecked()){ 
        countChecks = countChecks + 1; 
       } 
       else{ 
        countChecks = countChecks - 1; 
       } 

       if(check == true){ 
        selectAllListView.setItemChecked(0, false); 
        check = !check; 
       } 

       if(countChecks == pendingTaskListAssigned.getCount()){ 
        selectAllListView.setItemChecked(0, true); 
        check = ! check; 
       } 
      } 
     }); 
    } 

    //populating the arraylist, creating an adapter and setting it to a list view 
    private void generateListdata() { 
     pendingTasks.add(new pendingTasks("System Tasks", "Wembley GP", "Daily", R.drawable.pending_clock_icon, R.drawable.safety_dashboard)); 
     pendingTasks.add(new pendingTasks("Call answer speed", "Wembley GP", "Daily", R.drawable.pending_clock_icon, R.drawable.access_dashboard)); 
     pendingTasks.add(new pendingTasks("Appointment reasons", "Wembley GP", "Daily", R.drawable.pending_clock_icon, R.drawable.access_dashboard)); 

     ArrayAdapter<pendingTasks> adapter = new PendingTaskAdapter(getContext(), 0, pendingTasks); 
     pendingTaskList.setAdapter(adapter); 
     pendingTaskList.setOnItemClickListener(new android.widget.AdapterView.OnItemClickListener() { 
      public void onItemClick(AdapterView<?> parent, View view, 
            int position, long id) { 
       showInputDialog(); 

       if (position == 0) {} 

       if (position == 1) { 
        //Intent myIntent = new Intent(view.getContext(), AddUser.class); 
        //startActivityForResult(myIntent, 0); 
       } 

       if (position == 2) { 
        //Intent myIntent = new Intent(view.getContext(), ViewUser.class); 
        //startActivityForResult(myIntent, 0); 
       } 
      } 
     }); 
    } 

    private void generateselectall() { 
     selectallList= new ArrayList<Map<Integer,String>>(); 
     selectall= new HashMap<Integer, String>(); 

     selectall.put(1, "Select All"); 
     populateList(selectall,selectallList); 
     ArrayAdapter arrayAdapter = new ArrayAdapter<String>(getContext(), 
       android.R.layout.simple_list_item_single_choice, selectallList) 
     { 
      @Override 
      public View getView(int position, View convertView, ViewGroup parent){ 
       // Get the current item from ListView 
       View view = super.getView(position,convertView,parent); 
       TextView tv = (TextView) view.findViewById(android.R.id.text1); 
       tv.setTextColor(Color.BLACK); 
       tv.setTextSize(13); 
       ViewGroup.LayoutParams params = view.getLayoutParams(); 
       // Set the height of the Item View 
       params.height = LinearLayout.LayoutParams.WRAP_CONTENT; 
       view.setLayoutParams(params); 
       view.setPadding(37,0,10,10); 
       return view; 
      } 
     }; 



     selectAllListView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE); 
     selectAllListView.setAdapter(arrayAdapter); 
     selectAllListView.setOnItemClickListener(new AdapterView.OnItemClickListener() { 
      @Override 
      public void onItemClick(AdapterView<?> parent, View view, int position, long id) { 
       //Toast.makeText(getContext(), "Hello", Toast.LENGTH_SHORT).show(); 
       int firstListItem = pendingTaskListAssigned.getFirstVisiblePosition(); 
       int lastVisibleItem = pendingTaskListAssigned.getFirstVisiblePosition() + pendingTaskListAssigned.getChildCount() - 1; 
       check = ! check; 

       for(int i=0; i < pendingTaskListAssigned.getCount(); i++){ 
        if(i>lastVisibleItem || i<firstListItem){ 
         View item = (View) pendingTaskListAssigned.getAdapter().getView(i, null, pendingTaskListAssigned); 
         CheckBox checkbox = (CheckBox)item.findViewById(R.id.checkboxassigned); 
         checkbox.setChecked(check); 
        } 
        else{ 
         ViewGroup item = (ViewGroup)pendingTaskListAssigned.getChildAt(i - firstListItem); 
         CheckBox checkbox = (CheckBox)item.findViewById(R.id.checkboxassigned); 
         checkbox.setChecked(check); 
        } 
       } 

       if(check == true){ 
        countChecks = pendingTaskListAssigned.getCount(); 
       } 
       else{ 
        countChecks = 0; 
       } 
      } 
     }); 
    } 

    protected void showInputDialog() { 
     final Dialog dialog = new Dialog(getContext()); 
     dialog.requestWindowFeature(Window.FEATURE_NO_TITLE); 
     dialog.setContentView(R.layout.task_dialog); 
     dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT)); 
     tbutton = (ToggleButton)dialog.findViewById(R.id.toggleButton); 
     toollamp= (ImageButton)dialog.findViewById(R.id.lamptool); 
     tooli= (ImageButton)dialog.findViewById(R.id.itool); 
     tooldetails= (TextView) dialog.findViewById(R.id.tooldetail); 
     submit=(Button)dialog.findViewById(R.id.btsubmit); 

     toollamp.setOnClickListener(new View.OnClickListener(){ 

      @Override 
      public void onClick(View view) { 
       tooldetails.setText("Target for staff 2 rings and answer.Check daily for 2x 5 mins"); 
      } 
     }); 

     submit.setOnClickListener(new View.OnClickListener() { 

      @Override 
      public void onClick(View v) { 
       //Toast.makeText(getActivity(), "Dismiss", Toast.LENGTH_LONG).show(); 
       dialog.dismiss(); 
      } 
     }); 

     tooli.setOnClickListener(new View.OnClickListener(){ 

      @Override 
      public void onClick(View view) { 
       tooldetails.setText("Check daily for 2x 5 mins"); 
      } 
     }); 

     tbutton.setOnClickListener(new View.OnClickListener() { 

      @Override 
      public void onClick(View v) { 
       if(tbutton.isChecked()) { 
        Toast.makeText(getActivity(), "Toggle button is on", Toast.LENGTH_LONG).show(); 
       } 
       else { 
        Toast.makeText(getActivity(), "Toggle button is Off", Toast.LENGTH_LONG).show(); 
       } 
      } 
     }); 

     dialog.show(); 
    } 

    protected void showAssignTaskDialog() { 
     final Dialog dialog = new Dialog(getContext()); 
     dialog.requestWindowFeature(Window.FEATURE_NO_TITLE); 
     dialog.setContentView(R.layout.assign_task_dialog); 
     dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT)); 
     Close= (ImageButton)dialog.findViewById(R.id.close); 
     myself=(Button)dialog.findViewById(R.id.btmyself); 
     others=(Button)dialog.findViewById(R.id.btothers); 

     Close.setOnClickListener(new View.OnClickListener(){ 

      @Override 
      public void onClick(View view) { 
       dialog.dismiss(); 
      } 
     }); 

     myself.setOnClickListener(new View.OnClickListener() { 

      @Override 
      public void onClick(View v) { 
       Toast.makeText(getActivity(), "Myself", Toast.LENGTH_LONG).show(); 
      } 
     }); 

     others.setOnClickListener(new View.OnClickListener() { 

      @Override 
      public void onClick(View v) { 
       Toast.makeText(getActivity(), "Others", Toast.LENGTH_LONG).show(); 
       Intent intent= new Intent(getContext(), AssignTasks.class); 
       startActivity(intent); 
      } 
     }); 

     dialog.show(); 
    } 
} 

Answer 1

对于有此问题的人，请使用cardviews和recyclerviews。数据对于列表视图来说太多了。取而代之的是使用cardviews和recyclerviews，并且延迟消失了。

Answer 2

首先，我不能让你为什么创建片段两次

实际上，你在这里创建片段

private void createViewPager(ViewPager viewPager) { 
     adapter = new DashboardNew.ViewPagerAdapter(getChildFragmentManager()); 
     adapter.addFrag(new CompletedTasks(), "Completed"); 
     adapter.addFrag(new PendingTasks(), "Pending"); 
     viewPager.setAdapter(adapter); 
} 

然后你在这里创建它们。再次

@Override 
public Fragment getItem(int position) { 
    if (position == 0) 
     return new CompletedTasks(); 
    else 
     return new PendingTasks(); 
} 

我想正确的方法是去除这些线路

adapter.addFrag(new CompletedTasks(), "Completed"); 
adapter.addFrag(new PendingTasks(), "Pending"); 

在其他情况下，你将不得不与屏幕旋转的大问题。

您可以设置屏幕外的限制（默认情况下它的1只），因此片段将被创建一次，并且不会被删除

viewPager.setOffscreenPageLimit(2); 

而且我拒绝了解这些行的意思

completedTasks.add(new completedTasks(...); 

它是CompletedTasks片段吗？你添加什么以及如何？

Answer 3

片段的onCreate（）函数中没有这样的事情。

但它仍然滞后，对吧？我认为问题在于你的布局太重了，因为你在onCreateView（）中做的唯一工作就是设置你的布局。

请检查您的图像是否具有非常高的像素密度。这是最常见的错误。 Android系统需要花费时间将布局中的高像素图像转换为适合您的设备的较低像素密度，这需要时间并导致延迟。 其他原因可能是错误的布局层次结构。