LinearLayout 和 NestedScrollView 中的 RecyclerView - 如何滚动到某个位置的项目顶部？

Question

I implemented RecyclerView. I would like a view scroll to top of item on 5th position in RecyclerView. scrollToPosition(5) don't work

XML file:

<?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:card_view="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_marginTop="128dp"
    android:orientation="vertical">

    <androidx.core.widget.NestedScrollView
        android:id="@+id/nestedScrollView_mark"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <LinearLayout
            android:id="@+id/linearLayout_markView"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">

            <androidx.recyclerview.widget.RecyclerView
                android:id="@+id/recyclerView_marks"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginTop="1dp" />

            <LinearLayout
                android:id="@+id/linearLayout_behavior"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginBottom="10dp"
                android:background="@drawable/layout_bg"
                android:orientation="vertical"
                android:visibility="invisible">

in Fragment:

recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
recyclerView.getLayoutManager().scrollToPosition(5);
recyclerView.setAdapter(adapter);

Answer 1

The scrollToPosition() needs to be used with any of the following ways to restore the scroll position to the selected position.You can save the selected position in onPause() and then restore subsequently. There might be two useful ways :-

1. Using onSaveInstanceState() function to save the state as explained here .
2. Using Shared Prefereneces to store the position, and restoring the state after the onCreateView .