Android - NestedScrollView 内嵌 RecyclerView 滑动监听问题

1. 监听思路

NestedScrollView

RecyclerView

RecyclerView

NestedScrollView

RecyclerView

2. 基本布局

<android.support.v4.widget.SwipeRefreshLayout
android:id="@+id/baseSwipeRefresh"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior">

<android.support.v4.widget.NestedScrollView
android:id="@+id/baseViewContent"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fillViewport="true"
android:scrollbars="none"
app:layout_behavior="@string/appbar_scrolling_view_behavior">
<android.support.v7.widget.RecyclerView
android:id="@+id/baseViewPager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior">

</android.support.v4.widget.NestedScrollView>
</android.support.v4.widget.SwipeRefreshLayout>

NestedScrollView

android:fillViewport="true"

3.

RecyclerView

初始化

//设置layoutManager
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(mContext);
// auto measure : true
linearLayoutManager.setSmoothScrollbarEnabled(true);
linearLayoutManager.setAutoMeasureEnabled(true);
linearLayoutManager.setOrientation(VERTICAL);
recyclerView.setLayoutManager(linearLayoutManager);
// 设置为 true
recyclerView.setHasFixedSize(true);
recyclerView.setItemAnimator(new DefaultItemAnimator());
// 设置为 false
recyclerView.setNestedScrollingEnabled(false);

4.

NestedScrollView

滑动监听

mNestedScrollView.setOnScrollChangeListener(new NestedScrollView.OnScrollChangeListener() {
@Override
public void onScrollChange(NestedScrollView v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {
if (scrollY > oldScrollY) {
// 向下滑动
}

if (scrollY < oldScrollY) {
// 向上滑动
}

if (scrollY == 0) {
// 顶部
}

if (scrollY == (v.getChildAt(0).getMeasuredHeight() - v.getMeasuredHeight())) {
// 底部
}
}
});

5. 结语

NestedScrollView

RecyclerView

6. 题外话（一）

RecyclerView

的滑动监听

RecyclerView

/**
* 重写RecyclerView.OnScrollListener 判断滑动向上，向下，顶部，底部
*/
public static abstract class OnVerticalScrollListener extends RecyclerView.OnScrollListener {

@Override
public final void onScrolled(RecyclerView recyclerView, int dx, int dy) {

LogUtil.e("ddd" + dy);
if (!recyclerView.canScrollVertically(-1)) {
onScrolledToTop();
} else if (!recyclerView.canScrollVertically(1)) {
onScrolledToBottom();
} else if (dy < 0) {
onScrolledUp();
} else if (dy > 0) {
onScrolledDown();
}
}

//向上滑动
public void onScrolledUp() {
}

//向下滑动
public void onScrolledDown() {
}

//滑动底部
public void onScrolledToTop() {

}

//滑动顶部
public void onScrolledToBottom() {

}
}

protected RecyclerView.OnScrollListener getOnScrollListener() {
//上下滑动监听
return new OnVerticalScrollListener() {
@Override
public void onScrolledToBottom() {
if (!isLoading) {
page++;
onLoadNextPage(page);
isLoading = true;
}
}
};

}

7. 题外话（二）

RecyclerAdapter

的数据改变监听

notifyxxx

notifyDataSetChanged()

notifyItemChanged()

adapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
@Override
public void onChanged() {
super.onChanged();
checkAdapterEmpty();
}

@Override
public void onItemRangeInserted(int positionStart, int itemCount) {
super.onItemRangeInserted(positionStart, itemCount);
checkAdapterEmpty();
}

@Override
public void onItemRangeRemoved(int positionStart, int itemCount) {
super.onItemRangeRemoved(positionStart, itemCount);
checkAdapterEmpty();
}
});

完