FragmentPagerAdapter
abstract classFragmentPagerAdapter: PagerAdapter
kotlin.Any | ||
↳ | androidx.viewpager.widget.PagerAdapter | |
↳ | androidx.fragment.app.FragmentPagerAdapter |
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 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 Long |
Return a unique identifier for the item at the given 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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