dynamically add and remove view to viewpager

Question

I figured out a solution - please see my post in the Answer section below    In my app  the user will start with a single view of his data   I d like to add a ViewPager and allow the user to add more views as desired   How do I do this    I dont  want to use the FragmentPagerAdapter    I ve read countless posts and overviews but am still missing something   Here s what I think I understand   MainActivity creates a ViewPager and PagerAdapter   ViewPager pager   null  MainPagerAdapter adapter   null  public void onCreate  Bundle savedInstanceState      super onCreate  savedInstanceState     pager   new ViewPager  this     setContentView  pager      adapter   new MainPagerAdapter      pager setAdapter  adapter       View v0   code to create initial view      adapter add  v0  0             Use a PagerAdapter to provide the sets of view   For this it seems I need methods to add and remove views  something like this  obviously more is needed to tell the ViewPager stuff has changed and how to show the change   class MainPagerAdapter extends PagerAdapter        This holds all the currently displayable views  in order from left to right    private ArrayList lt View gt  views   new ArrayList lt View gt        public void addView  View v  int position          views add  position  v          public void removeView  int position          views remove  position           In addition  I need to implement the following vitual methods   I m lost here - what calls them and what are they supposed to do  ok  getCount is obvious        public object instantiateItem  ViewGroup pager  int position     public void destroyItem  ViewGroup  int  Object     public int getCount       public boolean isViewFromObject  View  Object      What are the ViewGroup params for - isn t the containing group the ViewPager itself    What does isViewFromObject do - how does an object get associated with a view in the first place  Should I be calling startUpdate and finishUdate when I add or remove views    Thanks

User · Answer

There are quite a few discussions around this topic

Although we see it often, using POSITION_NONE does not seem to be the way to go as it is very inefficient memory-wise.

Here in this question, we should consider using Alvaro's approach:

... is to setTag() method in instantiateItem() when instantiating a new view. Then instead of using notifyDataSetChanged(), you can use findViewWithTag() to find the view you want to update.

Here is a SO answer with code based on this idea

User · Answer

To remove you can use this directly   getSupportFragmentManager   beginTransaction   remove fragment                               commitAllowingStateLoss      fragment is the fragment you want to remove

User · Answer

I did a similar program  hope this would help you In its first activity four grid data can be selected  On the next activity  there is a view pager which contains two mandatory pages And 4 more pages will be there  which will be visible corresponding to the grid data selected    Following is the mainactivty MainActivity      package com example jeffy viewpagerapp      import android content Context      import android content Intent      import android content SharedPreferences      import android database Cursor      import android database SQLException      import android database sqlite SQLiteDatabase      import android database sqlite SQLiteOpenHelper      import android os Bundle      import android os Parcel      import android support design widget FloatingActionButton      import android support design widget Snackbar      import android support v7 app AppCompatActivity      import android support v7 widget Toolbar      import android util Log      import android view View      import android view Menu      import android view MenuItem      import android widget AdapterView      import android widget Button      import android widget GridView      import java lang reflect Array      import java util ArrayList      public class MainActivity extends AppCompatActivity       SharedPreferences pref      SharedPreferences Editor editor      GridView gridView      Button button      private static final String DATABASE NAME    dbForTest db       private static final int DATABASE VERSION   1      private static final String TABLE NAME    diary       private static final String TITLE    id       private static final String BODY    content       DBHelper  dbHelper   new DBHelper this       ArrayList lt String gt  frags   new ArrayList lt String gt         ArrayList lt FragmentArray gt  fragmentArray   new ArrayList lt FragmentArray gt         String   selectedData      Boolean port1 false port2 false port3 false port4 false      int Iport1 1 Iport2 1 Iport3 1 Iport4 1 location            This Data show in grid   Used by adapter           CustomGridAdapter customGridAdapter   new           CustomGridAdapter MainActivity this GRID DATA       static final String    GRID DATA   new String                  1                 2                3                 4              Override     protected void onCreate Bundle savedInstanceState            super onCreate savedInstanceState           setContentView R layout activity main           Toolbar toolbar    Toolbar  findViewById R id toolbar           setSupportActionBar toolbar           frags add  TabFragment3            frags add  TabFragment4            frags add  TabFragment5            frags add  TabFragment6            dbHelper   new DBHelper this           dbHelper insertContact 1 0           dbHelper insertContact 2 0           dbHelper insertContact 3 0           dbHelper insertContact 4 0           final Bundle selected   new Bundle            button    Button  findViewById R id button           pref   getApplicationContext   getSharedPreferences  MyPref   MODE PRIVATE           editor   pref edit            gridView    GridView  findViewById R id gridView1            gridView setAdapter customGridAdapter            gridView setOnItemClickListener new AdapterView OnItemClickListener                  Override             public void onItemClick AdapterView lt   gt  parent  View view  int position  long id                    view findViewById R id grid item image  setVisibility View VISIBLE                   location   position   1                  if  position    0                        Iport1                        Iport1   Iport1   2                      if  Iport1   2    1                              dbHelper updateContact 1 1                           view findViewById R id grid item image  setVisibility View VISIBLE                           dbHelper updateContact 1 1                         else                             dbHelper updateContact 1 0                           view findViewById R id grid item image  setVisibility View INVISIBLE                           dbHelper updateContact 1  0                                                           if  position    1                        Iport2                        Iport1   Iport1   2                      if  Iport2   2    1                              dbHelper updateContact 2 1                           view findViewById R id grid item image  setVisibility View VISIBLE                           dbHelper updateContact 2  1                         else                             dbHelper updateContact 2 0                           view findViewById R id grid item image  setVisibility View INVISIBLE                           dbHelper updateContact 2 0                                                           if  position    2                        Iport3                        Iport3   Iport3   2                      if  Iport3   2    1                              dbHelper updateContact 3 1                           view findViewById R id grid item image  setVisibility View VISIBLE                           dbHelper updateContact 3  1                         else                             dbHelper updateContact 3 0                           view findViewById R id grid item image  setVisibility View INVISIBLE                           dbHelper updateContact 3  0                                                           if  position    3                        Iport4                        Iport4   Iport4   2                      if  Iport4   2    1                              dbHelper updateContact 4 1                          view findViewById R id grid item image  setVisibility View VISIBLE                           dbHelper updateContact 4  1                         else                             dbHelper updateContact 4 0                          view findViewById R id grid item image  setVisibility View INVISIBLE                           dbHelper updateContact 4 0                                                                             button setOnClickListener new View OnClickListener                  Override             public void onClick View v                    editor putInt  port1   Iport1                   editor putInt  port2   Iport2                   editor putInt  port3   Iport3                   editor putInt  port4   Iport4                   Intent i   new Intent MainActivity this Main2Activity class                   if Iport1  1                      i putExtra  3   TabFragment3                    else                     i putExtra  3                        if Iport2  1                      i putExtra  4   TabFragment4                    else                     i putExtra  4                       if Iport3  1                      i putExtra  5    TabFragment5                    else                     i putExtra  5                       if Iport4  1                      i putExtra  6    TabFragment6                    else                     i putExtra  6                       dbHelper updateContact 0  Iport1                   dbHelper updateContact 1  Iport2                   dbHelper updateContact 2  Iport3                   dbHelper updateContact 3  Iport4                   startActivity i                                       Here TabFragment1 TabFragment2 etc are fragment to be displayed on the viewpager And I am not showing the layouts since they are out of scope of this project   MainActivity will intent to Main2Activity Main2Activity      package com example jeffy viewpagerapp   import android content Intent  import android database Cursor  import android os Bundle  import android support design widget CollapsingToolbarLayout  import android support design widget FloatingActionButton  import android support design widget Snackbar  import android support design widget TabLayout  import android support v4 view ViewPager  import android support v4 widget NestedScrollView  import android support v7 app AppCompatActivity  import android support v7 widget Toolbar  import android text TextUtils  import android util Log  import android view LayoutInflater  import android view Menu  import android view MenuItem  import android view View  import android widget FrameLayout   import java util ArrayList   public class Main2Activity extends AppCompatActivity        private ViewPager pager   null      private PagerAdapter pagerAdapter   null      DBHelper dbHelper      Cursor rs      int port1 port2 port3 port4        -----------------------------------------------------------------------------      Override     public void onCreate  Bundle savedInstanceState                super onCreate savedInstanceState           setContentView R layout activity main2           Toolbar toolbar    Toolbar  findViewById R id MyToolbar           setSupportActionBar toolbar            getSupportActionBar   setDisplayHomeAsUpEnabled true            CollapsingToolbarLayout collapsingToolbar                    CollapsingToolbarLayout  findViewById R id collapse toolbar             NestedScrollView scrollView    NestedScrollView  findViewById  R id nested           scrollView setFillViewport  true            ArrayList lt String  gt  selectedPort   new ArrayList lt String gt              Intent intent   getIntent            String Tab3   intent getStringExtra  3            String Tab4   intent getStringExtra  4            String Tab5   intent getStringExtra  5            String Tab6   intent getStringExtra  6             TabLayout tabLayout    TabLayout  findViewById R id tab layout           tabLayout addTab tabLayout newTab   setText  View             tabLayout addTab tabLayout newTab   setText  All              selectedPort add  TabFragment1            selectedPort add  TabFragment2            if Tab3  null  amp  amp   TextUtils isEmpty Tab3           selectedPort add Tab3           if Tab4  null  amp  amp   TextUtils isEmpty Tab4           selectedPort add Tab4           if Tab5  null  amp  amp   TextUtils isEmpty Tab5           selectedPort add Tab5           if Tab6  null  amp  amp   TextUtils isEmpty Tab6           selectedPort add Tab6              dbHelper   new DBHelper this             rs dbHelper getData 1             port1   rs getInt rs getColumnIndex  id                  rs dbHelper getData 2             port2   rs getInt rs getColumnIndex  id                  rs dbHelper getData 3             port3   rs getInt rs getColumnIndex  id                  rs dbHelper getData 4             port4   rs getInt rs getColumnIndex  id               Log i   gt  gt  gt  gt  gt  gt  gt  gt  gt  gt  gt  gt  gt  gt     port 1    port1    port 2    port2    port 3    port3    port 4    port4            if Tab3  null  amp  amp   TextUtils isEmpty Tab3           tabLayout addTab tabLayout newTab   setText  Tab 0             if Tab3  null  amp  amp   TextUtils isEmpty Tab4           tabLayout addTab tabLayout newTab   setText  Tab 1             if Tab3  null  amp  amp   TextUtils isEmpty Tab5           tabLayout addTab tabLayout newTab   setText  Tab 2             if Tab3  null  amp  amp   TextUtils isEmpty Tab6           tabLayout addTab tabLayout newTab   setText  Tab 3             tabLayout setTabGravity TabLayout GRAVITY FILL            final ViewPager viewPager    ViewPager  findViewById R id view pager           final PagerAdapter adapter   new PagerAdapter                  getSupportFragmentManager    tabLayout getTabCount    selectedPort           viewPager setAdapter adapter           viewPager addOnPageChangeListener new TabLayout TabLayoutOnPageChangeListener tabLayout            tabLayout setOnTabSelectedListener new TabLayout OnTabSelectedListener                  Override             public void onTabSelected TabLayout Tab tab                    viewPager setCurrentItem tab getPosition                                 Override             public void onTabUnselected TabLayout Tab tab                                 Override             public void onTabReselected TabLayout Tab tab                                         setContentView R layout activity main2             Toolbar toolbar    Toolbar  findViewById R id toolbar             setSupportActionBar toolbar              TabLayout tabLayout    TabLayout  findViewById R id tab layout             tabLayout addTab tabLayout newTab   setText  View               tabLayout addTab tabLayout newTab   setText  All               tabLayout addTab tabLayout newTab   setText  Tab 0               tabLayout addTab tabLayout newTab   setText  Tab 1               tabLayout addTab tabLayout newTab   setText  Tab 2               tabLayout addTab tabLayout newTab   setText  Tab 3               tabLayout setTabGravity TabLayout GRAVITY FILL               ViewPagerAdapter Viewpageradapter class  package com example jeffy viewpagerapp   import android os Bundle  import android support v4 app Fragment  import android support v4 app FragmentManager  import android support v4 app FragmentStatePagerAdapter  import android support v4 view ViewPager  import android view View  import android view ViewGroup   import java util ArrayList  import java util List          Created by Jeffy on 25-01-2016      public class PagerAdapter extends FragmentStatePagerAdapter       int mNumOfTabs       List lt String gt  values       public PagerAdapter FragmentManager fm  int NumOfTabs  List lt String gt  Port            super fm           this mNumOfTabs   NumOfTabs          this values  Port               Override     public Fragment getItem int position              String fragmentName   values get position           Class lt   gt  clazz   null          Object fragment   null          try               clazz   Class forName  com example jeffy viewpagerapp   fragmentName             catch  ClassNotFoundException e                e printStackTrace                      try               fragment   clazz newInstance              catch  InstantiationException e                e printStackTrace              catch  IllegalAccessException e                e printStackTrace                       return  Fragment  fragment              Override     public int getCount             return values size              Layout for main2activity acticity main2 xml       lt android support design widget CoordinatorLayout xmlns android  http   schemas android com apk res android          xmlns app  http   schemas android com apk res-auto          android id    id main content          android layout width  match parent          android layout height  match parent          android fitsSystemWindows  true  gt            lt android support design widget AppBarLayout             android id    id MyAppbar              android layout width  match parent              android layout height  256dp              android fitsSystemWindows  true  gt                lt android support design widget CollapsingToolbarLayout                 android id    id collapse toolbar                  android layout width  match parent                  android layout height  match parent                  app layout scrollFlags  scroll exitUntilCollapsed                  android background   color material deep teal 500                  android fitsSystemWindows  true  gt                    lt ImageView                     android id    id bgheader                      android layout width  match parent                      android layout height  match parent                      android scaleType  centerCrop                      android fitsSystemWindows  true                      android background   drawable screen                      app layout collapseMode  pin    gt                    lt android support v7 widget Toolbar                     android id    id MyToolbar                      android layout width  match parent                      android layout height   attr actionBarSize                      app layout collapseMode  parallax    gt                    lt  android support design widget CollapsingToolbarLayout gt            lt  android support design widget AppBarLayout gt            lt android support v4 widget NestedScrollView             android layout width  match parent              android id    id nested              android layout height  match parent              android layout gravity  fill vertical              app layout behavior   string appbar scrolling view behavior  gt        lt LinearLayout         android layout width  match parent          android layout height  wrap content          android orientation  vertical  gt           lt android support design widget TabLayout             android id    id tab layout              android layout width  match parent              android layout height  wrap content              android layout below    id MyToolbar              android background   attr colorPrimary              android elevation  6dp              android minHeight   attr actionBarSize              android theme   style ThemeOverlay AppCompat Dark ActionBar   gt             lt android support v4 view ViewPager             xmlns android  http   schemas android com apk res android              android id    id view pager              android layout width  match parent              android layout height  match parent   gt            lt  android support v4 view ViewPager gt       lt  LinearLayout gt             lt  android support v4 widget NestedScrollView gt        lt  android support design widget CoordinatorLayout gt   Mainactivity layout activity main xml           lt  xml version  1 0  encoding  utf-8   gt   lt RelativeLayout 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 layout width  match parent      android layout height  match parent      android paddingBottom   dimen activity vertical margin      android paddingLeft   dimen activity horizontal margin      android paddingRight   dimen activity horizontal margin      android paddingTop   dimen activity vertical margin      app layout behavior   string appbar scrolling view behavior      tools context  com example jeffy viewpagerapp MainActivity      tools showIn   layout activity main  gt     lt LinearLayout     android layout width  match parent      android layout height  wrap content      android orientation  vertical  gt        lt GridView xmlns android  http   schemas android com apk res android          android id    id gridView1          android numColumns  2          android gravity  center          android columnWidth  100dp          android stretchMode  columnWidth          android layout width  fill parent          android layout height  fill parent   gt        lt  GridView gt        lt Button         android layout width  match parent          android layout height  wrap content          android text  SAVE          android id    id button    gt    lt  LinearLayout gt       lt  RelativeLayout gt    Hope this would help someone    Click up button please if this helped you

User · Answer

I was looking for simple solution to remove views from viewpager  no fragments  dynamically  So  if you have some info  that your pages belongs to  you can set it to View as tag  Just like that  adapter code     Override public Object instantiateItem ViewGroup collection  int position        ImageView iv   new ImageView mContext       MediaMessage msg   mMessages get position                iv setTag media       return iv      Override public int getItemPosition  Object object        View o    View  object      int index   mMessages indexOf o getTag         if  index    -1          return POSITION NONE      else         return index      You just need remove your info from mMessages  and then call notifyDataSetChanged   for your adapter  Bad news there is no animation in this case

User · Answer

After figuring out which ViewPager methods are called by ViewPager and which are for other purposes  I came up with a solution   I present it here since I see a lot of people have struggled with this and I didn t see any other relevant answers    First  here s my adapter  hopefully comments within the code are sufficient   public class MainPagerAdapter extends PagerAdapter        This holds all the currently displayable views  in order from left to right    private ArrayList lt View gt  views   new ArrayList lt View gt          -----------------------------------------------------------------------------      Used by ViewPager    Object  represents the page  tell the ViewPager where the      page should be displayed  from left-to-right   If the page no longer exists       return POSITION NONE     Override   public int getItemPosition  Object object          int index   views indexOf  object       if  index    -1        return POSITION NONE      else       return index           -----------------------------------------------------------------------------      Used by ViewPager   Called when ViewPager needs a page to display  it is our job      to add the page to the container  which is normally the ViewPager itself   Since      all our pages are persistent  we simply retrieve it from our  views  ArrayList     Override   public Object instantiateItem  ViewGroup container  int position          View v   views get  position       container addView  v       return v           -----------------------------------------------------------------------------      Used by ViewPager   Called when ViewPager no longer needs a page to display  it      is our job to remove the page from the container  which is normally the      ViewPager itself   Since all our pages are persistent  we do nothing to the      contents of our  views  ArrayList     Override   public void destroyItem  ViewGroup container  int position  Object object          container removeView  views get  position             -----------------------------------------------------------------------------      Used by ViewPager  can be used by app as well       Returns the total number of pages that the ViewPage can display   This must      never be 0     Override   public int getCount            return views size             -----------------------------------------------------------------------------      Used by ViewPager     Override   public boolean isViewFromObject  View view  Object object          return view    object           -----------------------------------------------------------------------------      Add  view  to right end of  views        Returns the position of the new view       The app should call this to add pages  not used by ViewPager    public int addView  View v          return addView  v  views size              -----------------------------------------------------------------------------      Add  view  at  position  to  views        Returns position of new view       The app should call this to add pages  not used by ViewPager    public int addView  View v  int position          views add  position  v       return position           -----------------------------------------------------------------------------      Removes  view  from  views        Retuns position of removed view       The app should call this to remove pages  not used by ViewPager    public int removeView  ViewPager pager  View v          return removeView  pager  views indexOf  v             -----------------------------------------------------------------------------      Removes the  view  at  position  from  views        Retuns position of removed view       The app should call this to remove pages  not used by ViewPager    public int removeView  ViewPager pager  int position             ViewPager doesn t have a delete method  the closest is to set the adapter        again   When doing so  it deletes all its views   Then we can delete the view        from from the adapter and finally set the adapter to the pager again   Note        that we set the adapter to null before removing the view from  views  - that s        because while ViewPager deletes all its views  it will call destroyItem which        will in turn cause a null pointer ref      pager setAdapter  null       views remove  position       pager setAdapter  this        return position           -----------------------------------------------------------------------------      Returns the  view  at  position        The app should call this to retrieve a view  not used by ViewPager    public View getView  int position          return views get  position             Other relevant methods        finishUpdate - called by the ViewPager - we don t care about what pages the      pager is displaying so we don t use this method      And here s some snips of code showing how to use the adapter     class MainActivity extends Activity     private ViewPager pager   null    private MainPagerAdapter pagerAdapter   null       -----------------------------------------------------------------------------    Override   public void onCreate  Bundle savedInstanceState          super onCreate savedInstanceState       setContentView  R layout main activity            do other initialization  such as create an ActionBar          pagerAdapter   new MainPagerAdapter        pager    ViewPager  findViewById  R id view pager       pager setAdapter  pagerAdapter           Create an initial view to display  must be a subclass of FrameLayout      LayoutInflater inflater   context getLayoutInflater        FrameLayout v0    FrameLayout  inflater inflate  R layout one of my page layouts  null       pagerAdapter addView  v0  0       pagerAdapter notifyDataSetChanged             -----------------------------------------------------------------------------      Here s what the app should do to add a view to the ViewPager    public void addView  View newPage          int pageIndex   pagerAdapter addView  newPage          You might want to make  newPage  the currently displayed page      pager setCurrentItem  pageIndex  true            -----------------------------------------------------------------------------      Here s what the app should do to remove a view from the ViewPager    public void removeView  View defunctPage          int pageIndex   pagerAdapter removeView  pager  defunctPage          You might want to choose what page to display  if the current page was  defunctPage       if  pageIndex    pagerAdapter getCount          pageIndex--      pager setCurrentItem  pageIndex            -----------------------------------------------------------------------------      Here s what the app should do to get the currently displayed page    public View getCurrentPage            return pagerAdapter getView  pager getCurrentItem              -----------------------------------------------------------------------------      Here s what the app should do to set the currently displayed page    pageToShow  must      currently be in the adapter  or this will crash    public void setCurrentPage  View pageToShow          pager setCurrentItem  pagerAdapter getItemPosition  pageToShow   true           Finally  you can use the following for your activity main xml layout    lt  xml version  1 0  encoding  utf-8   gt   lt android support v4 view ViewPager     xmlns android  http   schemas android com apk res android      android id    id view pager      android layout width  match parent      android layout height  match parent   gt    lt  android support v4 view ViewPager gt

User · Answer

I ve created a custom PagerAdapters library to change items in PagerAdapters dynamically   You can change items dynamically like following by using this library    Override protected void onCreate Bundle savedInstanceState                            adapter   new MyStatePagerAdapter getSupportFragmentManager                                 new String    1    2    3           ViewPager findViewById R id view pager   setAdapter adapter        adapter add  4         adapter remove 0      class MyPagerAdapter extends ArrayViewPagerAdapter lt String gt         public MyPagerAdapter String   data            super data               Override     public View getView LayoutInflater inflater  ViewGroup container  String item  int position            View v   inflater inflate R layout item page  container  false             TextView  v findViewById R id item txt   setText item           return v            Thils library also support pages created by Fragments

User · Answer

I find a good solution for this issue  this solution can make it work and no need to recreate Fragments  My key point is     setup ViewPager every time you delete or add Tab Fragment   Override the getItemId method  return a specific id rather than position    Source Code  package com zq testviewpager   import android support annotation Nullable  import android support design widget TabLayout  import android support design widget FloatingActionButton  import android support design widget Snackbar  import android support v7 app AppCompatActivity  import android support v7 widget Toolbar   import android support v4 app Fragment  import android support v4 app FragmentManager  import android support v4 app FragmentPagerAdapter  import android support v4 view ViewPager  import android os Bundle  import android util Log  import android view LayoutInflater  import android view Menu  import android view MenuItem  import android view View  import android view ViewGroup   import android widget TextView   import java util ArrayList  import java util Arrays         Created by z8888q gmail com on 2017 5 31     Implement dynamic delete or add tab TAB C in this test code       public class MainActivity extends AppCompatActivity        private static final int TAB A   1001      private static final int TAB B   1002      private static final int TAB C   1003      private static final int TAB D   1004      private static final int TAB E   1005      private Tab   tabsArray   new Tab   new Tab TAB A   A   new Tab TAB B   B   new Tab TAB C   C   new Tab TAB D   D   new Tab TAB E   E          private ArrayList lt Tab gt  mTabs   new ArrayList lt  gt  Arrays asList tabsArray         private Tab   tabsArray2   new Tab   new Tab TAB A   A   new Tab TAB B   B   new Tab TAB D   D   new Tab TAB E   E          private ArrayList lt Tab gt  mTabs2   new ArrayList lt  gt  Arrays asList tabsArray2                    The   link android support v4 view PagerAdapter  that will provide        fragments for each of the sections  We use a          link FragmentPagerAdapter  derivative  which will keep every        loaded fragment in memory  If this becomes too memory intensive  it        may be best to switch to a          link android support v4 app FragmentStatePagerAdapter               private SectionsPagerAdapter mSectionsPagerAdapter                  The   link ViewPager  that will host the section contents              private ViewPager mViewPager      private TabLayout tabLayout        Override     protected void onCreate Bundle savedInstanceState            super onCreate savedInstanceState           setContentView R layout activity main            Toolbar toolbar    Toolbar  findViewById R id toolbar           setSupportActionBar toolbar              Create the adapter that will return a fragment for each of the three            primary sections of the activity          mSectionsPagerAdapter   new SectionsPagerAdapter mTabs  getSupportFragmentManager                 Set up the ViewPager with the sections adapter          mViewPager    ViewPager  findViewById R id container           mViewPager setAdapter mSectionsPagerAdapter            tabLayout    TabLayout  findViewById R id tabs           tabLayout setupWithViewPager mViewPager            FloatingActionButton fab    FloatingActionButton  findViewById R id fab           fab setOnClickListener new View OnClickListener                  Override             public void onClick View view                    Snackbar make view   Replace with your own action   Snackbar LENGTH LONG                           setAction  Action   null  show                                            Override     public boolean onCreateOptionsMenu Menu menu               Inflate the menu  this adds items to the action bar if it is present          getMenuInflater   inflate R menu menu main  menu           return true              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          int id   item getItemId               noinspection SimplifiableIfStatement         if  id    R id action settings                return true           else if  id    R id action delete                int currentItemPosition   mViewPager getCurrentItem                Tab currentTab   mTabs get currentItemPosition                if currentTab id    TAB C                   currentTab   mTabs get currentItemPosition    0   currentItemPosition  1   currentItemPosition - 1                              mSectionsPagerAdapter   new SectionsPagerAdapter mTabs2  getSupportFragmentManager                 mViewPager setAdapter mSectionsPagerAdapter               tabLayout setupWithViewPager mViewPager                 mViewPager setCurrentItem mTabs2 indexOf currentTab   false               return true           else if  id    R id action add                 int currentItemPosition   mViewPager getCurrentItem                Tab currentTab   mTabs2 get currentItemPosition                mSectionsPagerAdapter   new SectionsPagerAdapter mTabs  getSupportFragmentManager                 mViewPager setAdapter mSectionsPagerAdapter               tabLayout setupWithViewPager mViewPager                mViewPager setCurrentItem mTabs indexOf currentTab   false               return true           else          return super onOptionsItemSelected item                         A placeholder fragment containing a simple view              public static class PlaceholderFragment extends Fragment                          The fragment argument representing the section number for this            fragment                      private static final String ARG SECTION NUMBER    section number            public PlaceholderFragment                                       Returns a new instance of this fragment for the given section            number                      public static PlaceholderFragment newInstance int sectionNumber                PlaceholderFragment fragment   new PlaceholderFragment                Bundle args   new Bundle                args putInt ARG SECTION NUMBER  sectionNumber               fragment setArguments args               return fragment                      Override         public void onCreate  Nullable Bundle savedInstanceState                super onCreate savedInstanceState               Log e  TestViewPager    onCreate  getArguments   getInt ARG SECTION NUMBER                        Override         public void onDestroy                 super onDestroy                Log e  TestViewPager    onDestroy  getArguments   getInt ARG SECTION NUMBER                        Override         public View onCreateView LayoutInflater inflater  ViewGroup container                                   Bundle savedInstanceState                View rootView   inflater inflate R layout fragment main  container  false               TextView textView    TextView  rootView findViewById R id section label               textView setText getString R string section format  getArguments   getInt ARG SECTION NUMBER                 return rootView                                  A   link FragmentPagerAdapter  that returns a fragment corresponding to        one of the sections tabs pages              public class SectionsPagerAdapter extends FragmentPagerAdapter           ArrayList lt Tab gt  tabs           public SectionsPagerAdapter ArrayList lt Tab gt  tabs  FragmentManager fm                super fm               this tabs   tabs                      Override         public Fragment getItem int position                   getItem is called to instantiate the fragment for the given page                 Return a PlaceholderFragment  defined as a static inner class below               return PlaceholderFragment newInstance tabs get position  id                       Override         public int getCount                 return tabs size                        Override         public long getItemId int position                return tabs get position  id                      Override         public CharSequence getPageTitle int position                return tabs get position  title                       private static class Tab           String title          public int id           Tab int id  String title               this id   id              this title   title                      Override         public boolean equals Object obj                if obj instanceof Tab                   return   Tab obj  id    id               else                  return false                                    Code is at my Github Gist

User · Answer

Here s an alternative solution to this question  My adapter       private class PagerAdapter extends FragmentPagerAdapter implements                      ViewPager OnPageChangeListener  TabListener        private List lt Fragment gt  mFragments   new ArrayList lt Fragment gt         private ViewPager mPager      private ActionBar mActionBar       private Fragment mPrimaryItem       public PagerAdapter FragmentManager fm  ViewPager vp  ActionBar ab            super fm           mPager   vp          mPager setAdapter this           mPager setOnPageChangeListener this           mActionBar   ab             public void addTab PartListFragment frag            mFragments add frag           mActionBar addTab mActionBar newTab   setTabListener this                               setText frag getPartCategory                  Override     public Fragment getItem int position            return mFragments get position               Override     public int getCount             return mFragments size                    non-Javadoc          see android support v4 app FragmentStatePagerAdapter setPrimaryItem android view ViewGroup  int  java lang Object               Override     public void setPrimaryItem ViewGroup container  int position              Object object            super setPrimaryItem container  position  object           mPrimaryItem    Fragment  object                  non-Javadoc          see android support v4 view PagerAdapter getItemPosition java lang Object               Override     public int getItemPosition Object object            if  object    mPrimaryItem                return POSITION UNCHANGED                    return POSITION NONE              Override     public void onTabSelected Tab tab  FragmentTransaction ft            mPager setCurrentItem tab getPosition                 Override     public void onTabUnselected Tab tab  FragmentTransaction ft            Override     public void onTabReselected Tab tab  FragmentTransaction ft            Override     public void onPageScrollStateChanged int arg0            Override     public void onPageScrolled int arg0  float arg1  int arg2            Override     public void onPageSelected int position            mActionBar setSelectedNavigationItem position                         This method removes the pages from ViewPager             public void removePages             mActionBar removeAllTabs                           call to ViewPage to remove the pages         vp removeAllViews            mFragments clear               make this to update the pager         vp setAdapter null           vp setAdapter pagerAdapter             Code to remove and add dynamically    remove the pages  basically call to method removeAllViews from  ViewPager  pagerAdapter removePages     pagerAdapter addPage pass your fragment     After the advice of Peri Hartman  it started to work after I set null do ViewPager adapter and put the adapter again after the views removed  Before this the page 0 doesnt showed its list contents   Thanks

[android] dynamically add and remove view to viewpager

Examples related to android

Examples related to android-viewpager

Examples related to swipe