android.support.v13.app
Class FragmentPagerAdapter

java.lang.Object
  extended by android.support.v4.view.PagerAdapter
      extended by android.support.v13.app.FragmentPagerAdapter

public abstract class FragmentPagerAdapter
extends android.support.v4.view.PagerAdapter

Implementation of PagerAdapter that represents each page as a Fragment that is persistently kept in the fragment manager as long as the user can return to the page.

This version of the pager is best for use when there are a handful of typically more static fragments to be paged through, such as a set of tabs. The fragment of each page the user visits will be kept in memory, though its view hierarchy may be destroyed when not visible. This can result in using a significant amount of memory since fragment instances can hold on to an arbitrary amount of state. For larger sets of pages, consider FragmentStatePagerAdapter.

When using FragmentPagerAdapter the host ViewPager must have a valid ID set.

Subclasses only need to implement getItem(int) and PagerAdapter.getCount() to have a working adapter.

Here is an example implementation of a pager containing fragments of lists:

The R.layout.fragment_pager resource of the top-level fragment is:

The R.layout.fragment_pager_list resource containing each individual fragment's layout is:


Field Summary
 
Fields inherited from class android.support.v4.view.PagerAdapter
POSITION_NONE, POSITION_UNCHANGED
 
Constructor Summary
FragmentPagerAdapter(android.app.FragmentManager fm)
           
 
Method Summary
 void destroyItem(android.view.ViewGroup container, int position, java.lang.Object object)
           
 void finishUpdate(android.view.ViewGroup container)
           
abstract  android.app.Fragment getItem(int position)
          Return the Fragment associated with a specified position.
 long getItemId(int position)
          Return a unique identifier for the item at the given position.
 java.lang.Object instantiateItem(android.view.ViewGroup container, int position)
           
 boolean isViewFromObject(android.view.View view, java.lang.Object object)
           
 void restoreState(android.os.Parcelable state, java.lang.ClassLoader loader)
           
 android.os.Parcelable saveState()
           
 void setPrimaryItem(android.view.ViewGroup container, int position, java.lang.Object object)
           
 void startUpdate(android.view.ViewGroup container)
           
 
Methods inherited from class android.support.v4.view.PagerAdapter
destroyItem, finishUpdate, getCount, getItemPosition, getPageTitle, getPageWidth, instantiateItem, notifyDataSetChanged, registerDataSetObserver, setPrimaryItem, startUpdate, unregisterDataSetObserver
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

FragmentPagerAdapter

public FragmentPagerAdapter(android.app.FragmentManager fm)
Method Detail

getItem

public abstract android.app.Fragment getItem(int position)
Return the Fragment associated with a specified position.


startUpdate

public void startUpdate(android.view.ViewGroup container)
Overrides:
startUpdate in class android.support.v4.view.PagerAdapter

instantiateItem

public java.lang.Object instantiateItem(android.view.ViewGroup container,
                                        int position)
Overrides:
instantiateItem in class android.support.v4.view.PagerAdapter

destroyItem

public void destroyItem(android.view.ViewGroup container,
                        int position,
                        java.lang.Object object)
Overrides:
destroyItem in class android.support.v4.view.PagerAdapter

setPrimaryItem

public void setPrimaryItem(android.view.ViewGroup container,
                           int position,
                           java.lang.Object object)
Overrides:
setPrimaryItem in class android.support.v4.view.PagerAdapter

finishUpdate

public void finishUpdate(android.view.ViewGroup container)
Overrides:
finishUpdate in class android.support.v4.view.PagerAdapter

isViewFromObject

public boolean isViewFromObject(android.view.View view,
                                java.lang.Object object)
Specified by:
isViewFromObject in class android.support.v4.view.PagerAdapter

saveState

public android.os.Parcelable saveState()
Overrides:
saveState in class android.support.v4.view.PagerAdapter

restoreState

public void restoreState(android.os.Parcelable state,
                         java.lang.ClassLoader loader)
Overrides:
restoreState in class android.support.v4.view.PagerAdapter

getItemId

public long getItemId(int position)
Return a unique identifier for the item at the given position.

The default implementation returns the given position. Subclasses should override this method if the positions of items can change.

Parameters:
position - Position within this adapter
Returns:
Unique identifier for the item at position