背景
假设我有一个垂直的 RecyclerView，其中每一行都是一个水平的 RecyclerView。
我想做的是，无论您滚动哪个水平 RecyclerViews，所有其他 RecyclerViews 都会相应滚动，并且始终与完全相同的滚动 X 坐标同步
问题
我实际上对基本操作做得很好：
它的工作原理是拥有一个所有水平 RecyclerView 都具有的滚动侦听器，但是当一个开始滚动时，它是唯一拥有它的侦听器，同时它也会影响其他人一起滚动。
但是，我所做的有两个主要问题：
在一些（水平）滚动操作中（可能是一些手势，比如 fling），多个 RecyclerView 的滚动是不同步的，所以有些在 X 坐标中，与其他的不同。
垂直滚动时，我无法正确设置 X 坐标。不仅如此，当我期望调用垂直 RecyclerView 的 onBindViewHolder 时，它不会被调用（当我滚动很多时调用，而不仅仅是当我看到重新显示使用过的对象时调用）。
我试过的
这是当前代码：
MainActivity.java
public class MainActivity extends AppCompatActivity {
int mCurX = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final RecyclerView mainRecyclerView = (RecyclerView) findViewById(R.id.activity_main);
final LinearLayoutManager verticalLinearLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
mainRecyclerView.setLayoutManager(verticalLinearLayoutManager);
final LayoutInflater layoutInflater = LayoutInflater.from(this);
final OnScrollListener masterOnScrollListener = new OnScrollListener() {
RecyclerView masterRecyclerView = null;
@Override
public void onScrollStateChanged(final RecyclerView recyclerView, final int newState) {
super.onScrollStateChanged(recyclerView, newState);
switch (newState) {
case RecyclerView.SCROLL_STATE_IDLE:
if (masterRecyclerView != null) {
masterRecyclerView = null;
final int firstVisibleItemPosition = verticalLinearLayoutManager.findFirstVisibleItemPosition();
final int lastVisibleItemPosition = verticalLinearLayoutManager.findLastVisibleItemPosition();
for (int i = firstVisibleItemPosition; i <= lastVisibleItemPosition; ++i) {
RecyclerView horizontalRecyclerView = (RecyclerView) mainRecyclerView.findViewHolderForAdapterPosition(i).itemView;
if (horizontalRecyclerView != recyclerView)
horizontalRecyclerView.addOnScrollListener(this);
}
}
break;
case RecyclerView.SCROLL_STATE_SETTLING:
//TODO fix out-of-sync scrolling issues, probably here
case RecyclerView.SCROLL_STATE_DRAGGING:
if (masterRecyclerView == null) {
masterRecyclerView = recyclerView;
final int firstVisibleItemPosition = verticalLinearLayoutManager.findFirstVisibleItemPosition();
final int lastVisibleItemPosition = verticalLinearLayoutManager.findLastVisibleItemPosition();
for (int i = firstVisibleItemPosition; i <= lastVisibleItemPosition; ++i) {
RecyclerView horizontalRecyclerView = (RecyclerView) mainRecyclerView.findViewHolderForAdapterPosition(i).itemView;
if (horizontalRecyclerView != recyclerView)
horizontalRecyclerView.removeOnScrollListener(this);
}
}
}
}
@Override
public void onScrolled(final RecyclerView recyclerView, final int dx, final int dy) {
super.onScrolled(recyclerView, dx, dy);
mCurX += dx;
final int firstVisibleItemPosition = verticalLinearLayoutManager.findFirstVisibleItemPosition();
final int lastVisibleItemPosition = verticalLinearLayoutManager.findLastVisibleItemPosition();
for (int i = firstVisibleItemPosition; i <= lastVisibleItemPosition; ++i) {
RecyclerView horizontalRecyclerView = (RecyclerView) mainRecyclerView.findViewHolderForAdapterPosition(i).itemView;
if (horizontalRecyclerView != recyclerView)
horizontalRecyclerView.scrollBy(dx, dy);
}
}
};
mainRecyclerView.setAdapter(new Adapter() {
@Override
public ViewHolder onCreateViewHolder(final ViewGroup parent, final int viewType) {
RecyclerView horizontalRecyclerView = (RecyclerView) layoutInflater.inflate(R.layout.horizontal_recycler_view, parent, false);
horizontalRecyclerView.setLayoutManager(new LinearLayoutManager(MainActivity.this, LinearLayoutManager.HORIZONTAL, false));
horizontalRecyclerView.addOnScrollListener(masterOnScrollListener);
final ViewHolder horizontalViewHolder = new ViewHolder(horizontalRecyclerView) {
};
horizontalRecyclerView.setAdapter(new Adapter() {
@Override
public ViewHolder onCreateViewHolder(final ViewGroup parent, final int viewType) {
return new ViewHolder(layoutInflater.inflate(R.layout.single_item, parent, false)) {
};
}
@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
((TextView) holder.itemView).setText("horizontalRecyclerView:" + horizontalViewHolder.getAdapterPosition() + "\nitem:" + position);
}
@Override
public int getItemCount() {
return 100;
}
});
return horizontalViewHolder;
}
@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
//TODO check why this isn't called for some cases
RecyclerView recyclerView = (RecyclerView) holder.itemView;
recyclerView.removeOnScrollListener(masterOnScrollListener);
//TODO scroll to correct location here. The below code doesn't seem to work at all
recyclerView.scrollToPosition(0);
recyclerView.scrollBy(mCurX,0);
recyclerView.addOnScrollListener(masterOnScrollListener);
recyclerView.getAdapter().notifyDataSetChanged();
}
@Override
public int getItemCount() {
return 40;
}
});
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.RecyclerView
android:id="@+id/activity_main"
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="match_parent"
tools:context="lb.com.nestedallscrollingrecyclerviewtest.MainActivity"/>
Horizontal_recycler_view.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.RecyclerView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="100dp"/>
single_item.xml
<?xml version="1.0" encoding="utf-8"?>
<TextView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:gravity="center"
android:orientation="vertical"
android:padding="10dp"/>
问题
导致它无法滚动同步的代码有什么问题？
是否有可能我也没有获得我应该拥有的所有 RecyclerViews？
当我期望它时，垂直 RecyclerView 的 onBindViewHolder 怎么没有被调用？
如何在垂直的 onBindViewHolder 中将水平 RecyclerView 的 x 坐标滚动设置为其他滚动？
我不确定这是否是个问题，但如果每个水平 RecyclerView 中的每个项目的宽度可能与其他项目不同，我该怎么办？