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    <p>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. </p> <p>First, here's my adapter; hopefully comments within the code are sufficient:</p> <pre><code>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. } </code></pre> <p>And here's some snips of code showing how to use the adapter. </p> <pre><code>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); } } </code></pre> <p>Finally, you can use the following for your <code>activity_main.xml</code> layout:</p> <pre><code>&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; </code></pre>
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    1. POdynamically add and remove view to viewpager
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    1. COthanks for the post .. I already done this thing but I have an query that is : How to clear the the getCount Value ?
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      1. USAkarsh M
    2. COgetCount() reflects the number of fragments. So, if you remove all the fragments, getCount() will return 0.
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    3. COafter of pagerAdapter.addView (v0, 0); add the following line pagerAdapter.notifyDataSetChanged();
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      1. USDavid Toledo
 

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