FragmentStatePagerAdapter
abstract classFragmentStatePagerAdapter: PagerAdapter
kotlin.Any | ||
↳ | androidx.viewpager.widget.PagerAdapter | |
↳ | androidx.fragment.app.FragmentStatePagerAdapter |
Implementation of PagerAdapter
that uses a Fragment
to manage each page. This class also handles saving and restoring of fragment's state.
This version of the pager is more useful when there are a large number of pages, working more like a list view. When pages are not visible to the user, their entire fragment may be destroyed, only keeping the saved state of that fragment. This allows the pager to hold on to much less memory associated with each visited page as compared to FragmentPagerAdapter
at the cost of potentially more overhead when switching between pages.
When using FragmentPagerAdapter the host ViewPager must have a valid ID set.
Subclasses only need to implement getItem(int)
and 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:
Summary
Constants | |
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static Int |
Indicates that only the current fragment will be in the |
static Int |
Indicates that |
Inherited constants | |
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Public constructors | |
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<init>(@NonNull fm: FragmentManager) Constructor for |
|
<init>(@NonNull fm: FragmentManager, behavior: Int) Constructor for |
Public methods | |
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open Unit |
destroyItem(@NonNull container: ViewGroup, position: Int, @NonNull object: Any) |
open Unit |
finishUpdate(@NonNull container: ViewGroup) |
abstract Fragment |
Return the Fragment associated with a specified position. |
open Any |
instantiateItem(@NonNull container: ViewGroup, position: Int) |
open Boolean |
isViewFromObject(@NonNull view: View, @NonNull object: Any) |
open Unit |
restoreState(@Nullable state: Parcelable?, @Nullable loader: ClassLoader?) |
open Parcelable? | |
open Unit |
setPrimaryItem(@NonNull container: ViewGroup, position: Int, @NonNull object: Any) |
open Unit |
startUpdate(@NonNull container: ViewGroup) |
Inherited functions | |
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