我知道它已经很老了，但是我从这里或从外部网页搜索并尝试许多解决方案的确很累
问题是：当从API调用数据到Vertical RecyclerView时，它将加载所有数据而无需考虑分页
可在水平“回收站”视图中成功使用
并且没有任何滚动或屏幕触摸
NestedScroll视图按以下顺序包含2个回收站
NestedScrollView作为父级
HorizontalRecyclerView作为子元素
VerticalRecyclerView作为子项
我的XML文件 ：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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="wrap_content"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context="com.organizers_group.stadfm.Activities.NewsFeedHome"
tools:showIn="@layout/app_bar_news_feed_home">
<android.support.v4.widget.NestedScrollView
android:id="@+id/nestedScroll"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:scrollbars="none"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
android:fillViewport="true">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingTop="@dimen/_5dp"
android:paddingBottom="@dimen/_7dp">
<RelativeLayout
android:id="@+id/linearLayout2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="8dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.0">
<TextView
android:id="@+id/horizontalTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/trending_stories"
android:layout_marginStart="@dimen/_10dp"
android:paddingTop="@dimen/_10dp"
android:paddingBottom="@dimen/_10dp"
android:fontFamily="@font/avenir_heavy"
android:textColor="@color/trending_stories_color"
android:textSize="@dimen/_20sp"/>
<io.supercharge.shimmerlayout.ShimmerLayout
android:id="@+id/shimmer_horizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_below="@+id/horizontalTitle"
app:shimmer_animation_duration="1200">
<!-- Adding rows of placeholders -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<include layout="@layout/place_holder" />
<include layout="@layout/place_holder" />
<include layout="@layout/place_holder" />
</LinearLayout>
</io.supercharge.shimmerlayout.ShimmerLayout>
<android.support.v7.widget.RecyclerView
android:id="@+id/horizontalRecycler"
android:layout_width="match_parent"
android:layout_below="@+id/trending_story"
android:layout_height="wrap_content"
android:orientation="horizontal" />
<ProgressBar
android:id="@+id/pBLoading"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:indeterminate="true"
android:visibility="invisible"
android:layout_alignParentBottom="true"
style="?android:attr/progressBarStyleHorizontal" />
</RelativeLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_below="@+id/linearLayout2"
android:orientation="vertical"
android:layout_margin="@dimen/_8dp"
android:descendantFocusability="blocksDescendants"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/linearLayout2"
app:layout_constraintVertical_bias="0.032"
app:layout_constraintVertical_weight="1">
<LinearLayout
android:id="@+id/storiesLayout"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="@dimen/_10dp"
android:paddingBottom="@dimen/_5dp"
android:text="@string/your_stories"
android:fontFamily="@font/avenir_heavy"
android:textColor="@color/stories_color"
android:textSize="@dimen/_20sp" />
<ImageView
android:id="@+id/moreStoriesImg"
android:layout_width="@dimen/_40dp"
android:layout_height="@dimen/_40dp"
android:src="@drawable/more"
android:layout_gravity="center"/>
</LinearLayout>
<io.supercharge.shimmerlayout.ShimmerLayout
android:id="@+id/shimmer_vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@id/story_layout"
android:orientation="vertical"
app:shimmer_animation_duration="1200">
<!-- Adding placeholders -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<include layout="@layout/place_holder" />
<include layout="@layout/place_holder" />
</LinearLayout>
</io.supercharge.shimmerlayout.ShimmerLayout>
<!-- problem is with the following recycler-->
<android.support.v7.widget.RecyclerView
android:id="@+id/verticalRecycler"
android:layout_width="match_parent"
android:layout_below="@+id/story_layout"
android:layout_height="wrap_content"
android:nestedScrollingEnabled="false"
app:layoutManager="android.support.v7.widget.LinearLayoutManager"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
/>
<ProgressBar
android:id="@+id/pBLoading"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:indeterminate="true"
android:visibility="invisible"
android:layout_alignParentBottom="true"
style="?android:attr/progressBarStyleHorizontal" />
</RelativeLayout>
</RelativeLayout>
</android.support.v4.widget.NestedScrollView>
</LinearLayout>
EndlessRecyclerViewScrollListener类（来自stackOverFlow的 ）
package com.organizers_group.stadfm.Adapters;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
public abstract class EndlessRecyclerViewScrollListener extends
RecyclerView.OnScrollListener {
// The minimum amount of items to have below your current scroll position
// before loading more.
private int visibleThreshold = 5;
// The current offset index of data you have loaded
private int currentPage = 1;
// The total number of items in the dataset after the last load
private int previousTotalItemCount = 0;
// True if we are still waiting for the last set of data to load.
private boolean loading = true;
// Sets the starting page index
private int startingPageIndex = 1;
RecyclerView.LayoutManager mLayoutManager;
public EndlessRecyclerViewScrollListener(LinearLayoutManager layoutManager) {
this.mLayoutManager = layoutManager;
}
public EndlessRecyclerViewScrollListener(GridLayoutManager layoutManager) {
this.mLayoutManager = layoutManager;
visibleThreshold = visibleThreshold * layoutManager.getSpanCount();
}
public EndlessRecyclerViewScrollListener(StaggeredGridLayoutManager layoutManager) {
this.mLayoutManager = layoutManager;
visibleThreshold = visibleThreshold * layoutManager.getSpanCount();
}
public int getLastVisibleItem(int[] lastVisibleItemPositions) {
int maxSize = 0;
for (int i = 0; i < lastVisibleItemPositions.length; i++) {
if (i == 0) {
maxSize = lastVisibleItemPositions[i];
}
else if (lastVisibleItemPositions[i] > maxSize) {
maxSize = lastVisibleItemPositions[i];
}
}
return maxSize;
}
// This happens many times a second during a scroll, so be wary of the code you place here.
// We are given a few useful parameters to help us work out if we need to load some more data,
// but first we check if we are waiting for the previous load to finish.
@Override
public void onScrolled(RecyclerView view, int dx, int dy) {
int lastVisibleItemPosition = 0;
int totalItemCount = mLayoutManager.getItemCount();
if (mLayoutManager instanceof StaggeredGridLayoutManager) {
int[] lastVisibleItemPositions = ((StaggeredGridLayoutManager) mLayoutManager).findLastVisibleItemPositions(null);
// get maximum element within the list
lastVisibleItemPosition = getLastVisibleItem(lastVisibleItemPositions);
} else if (mLayoutManager instanceof GridLayoutManager) {
lastVisibleItemPosition = ((GridLayoutManager) mLayoutManager).findLastVisibleItemPosition();
} else if (mLayoutManager instanceof LinearLayoutManager) {
lastVisibleItemPosition = ((LinearLayoutManager) mLayoutManager).findLastVisibleItemPosition();
}
// If the total item count is zero and the previous isn't, assume the
// list is invalidated and should be reset back to the initial state
if (totalItemCount < previousTotalItemCount) {
this.currentPage = this.startingPageIndex;
this.previousTotalItemCount = totalItemCount;
if (totalItemCount == 0) {
this.loading = true;
}
}
// If it’s still loading, we check to see if the dataset count has
// changed, if so we conclude it has finished loading and update the current page
// number and total item count.
if (loading && (totalItemCount > previousTotalItemCount)) {
loading = false;
previousTotalItemCount = totalItemCount;
}
// If it isn’t currently loading, we check to see if we have breached
// the visibleThreshold and need to reload more data.
// If we do need to reload some more data, we execute onLoadMore to fetch the data.
// threshold should reflect how many total columns there are too
if (!loading && (lastVisibleItemPosition + visibleThreshold) > totalItemCount) {
currentPage++;
onLoadMore(currentPage, totalItemCount, view);
loading = true;
}
}
// Call this method whenever performing new searches
public void resetState() {
this.currentPage = this.startingPageIndex;
this.previousTotalItemCount = 0;
this.loading = true;
}
// Defines the process for actually loading more data based on page
public abstract void onLoadMore(int page, int totalItemsCount, RecyclerView view);
}
我的活动 ：
RecyclerView horizontalRecyclerView = findViewById(R.id.horizontalRecycler);
horizontalRecyclerView.setHasFixedSize(true);
LinearLayoutManager horizontalLayoutManager = new LinearLayoutManager(this , LinearLayoutManager.HORIZONTAL , false);
horizontalRecyclerView.setLayoutManager(horizontalLayoutManager);
// get trending post
final int trendingPage = 1;
myCustomAdapter = new MyCustomAdapter( this , getPosts(Page));
horizontalRecyclerView.setAdapter(myCustomAdapter);
myCustomAdapter.notifyDataSetChanged();
EndlessRecyclerViewScrollListener scrollListener = new EndlessRecyclerViewScrollListener(horizontalLayoutManager) {
@Override
public void onLoadMore(int page, int totalItemsCount, RecyclerView view) {
// Triggered only when new data needs to be appended to the list
// Add whatever code is needed to append new items to the bottom of the list
showProgressView(ProgressBar);
getPosts(page);
}
};
// Adds the scroll listener to RecyclerView
horizontalRecyclerView.addOnScrollListener(scrollListener);
// End Of horizontalRecyclerView
// Stories RecyclerView
RecyclerView verticalRecycler = findViewById(R.id.verticalRecycler);
verticalRecycler.setHasFixedSize(true);
verticalRecycler.setNestedScrollingEnabled(false);
LinearLayoutManager verticalLayoutManager = new LinearLayoutManager(this , LinearLayoutManager.VERTICAL , false);
verticalRecycler.setLayoutManager(verticalLayoutManager);
// get mixed posts
verticalAdapter = new VerticalAdapter( this , getStoriesPosts(1));
verticalRecycler.setAdapter(verticalAdapter);
verticalAdapter.notifyDataSetChanged();
EndlessRecyclerViewScrollListener mixedScrollListener = new EndlessRecyclerViewScrollListener(verticalLayoutManager) {
@Override
public void onLoadMore(int page, int totalItemsCount, RecyclerView view) {
// Triggered only when new data needs to be appended to the list
// Add whatever code is needed to append new items to the bottom of the list
showProgressView(progressBar);
getStoriesPosts(page);
}
};
// Adds the scroll listener to RecyclerView
storiesRecyclerView.addOnScrollListener(mixedScrollListener);
// End Of Mixed Stories
请帮助我！
如何使用该垂直RecyclerView分页？
非常感谢您的帮助
预先感谢。
答案 0 :(得分：0)
为解决这一挑战，我执行以下步骤：
1-用于 XML文件或 EndlessRecyclerViewScrollListener 无变化
2-用于 我的活动 。我删除了垂直回收站的EndlessRecyclerViewScrollListener，并定义了NestedScrollListener实例，然后按如下所示设置OnScrollChangeListener：
boolean loading = true;
int pageNumber = 1;
NestedScrollView scroller = findViewById(R.id.nestedScroll);
if (scroller != null) {
scroller.setOnScrollChangeListener((NestedScrollView.OnScrollChangeListener) (v, scrollX, scrollY, oldScrollX, oldScrollY) -> {
if (scrollY > oldScrollY) {
Log.i(TAG, "Scroll DOWN");
}
if (scrollY < oldScrollY) {
Log.i(TAG, "Scroll UP");
}
if (scrollY == 0) {
Log.i(TAG, "TOP SCROLL");
}
if (scrollY == ( v.getChildAt(0).getMeasuredHeight() - v.getMeasuredHeight() )) {
Log.i(TAG, "BOTTOM SCROLL");
// here where the trick is going
if (loading){
pageNumber++;
showProgressView(mixedProgressBar);
// calling from adapter addToExistingList(list)
// with the defined Adapter instance
verticalAdapter.addToExistingList(getPosts(pageNumber));
// reset the boolean(loading) to prevent
// auto loading data from APi
loading = false;
}
}
});
}
3-对于VerticalAdapter，我添加以下方法：
public void addToExistingList(List<DataModel> dataModelList){
// update oldDataModelList with newer data from pagination
oldDataModelList.retainAll(dataModelList);
notifyItemRangeChanged(oldDataModelList.size()-1 , dataModelList.size());
}
对于获取数据成功，getPosts（pageNumber）的4-p重新分配了布尔值（正在加载）
getPosts（pageNumber）是一种从API调用数据的方法
JsonArrayRequest arrayRequest = new JsonArrayRequest(Request.Method.GET,baseAPI,
response1 -> {
try {
// doing stuff to invoke your data
// re-assign loading variable to load again
loading = true;
} catch (JSONException e) {
e.printStackTrace();
}
答案 1 :(得分：0)
基于Android文档：
切勿将RecyclerView或ListView添加到滚动视图。这样做会导致不良的用户界面性能和不良的用户体验。
最好的新方法是使用MergeAdapter。它已添加到Recyclerview v1.2.0alpha。因此，添加此依赖项：
implementation "androidx.recyclerview:recyclerview:1.2.0-alpha03"
然后创建一个MakeAdapter实例并在其上传递您的适配器，然后将其设置为RecyclerViewAdapter：
MergeAdapter ma = new (firstAdapter, secondAdapter);
myRecyclerView.setAdapter(ma);
然后制作Make和Simple ViewHolder，并在其上放置第一个布局。然后使MergeAdapter，然后添加布局的适配器，然后添加PagedList的适配器，然后添加PagedList的适配器：
MergeAdapter ma = new MergeAdapter();
ma.addAdaper(simpleAdapter);
ma.addAdapter(pagedListAdapter);
然后将这个mergeAdapter设置为recyclerView的适配器；
myRecyclerView.setAdapter(ma);