RecyclerView一次加载所有项目，导致应用程序无响应错误

Question

我有一个具有以下结构的布局：

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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=".Activites.Settings.ContactsActivity">

    <FrameLayout
        android:id="@+id/fl_contacts"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_marginTop="5dp"
        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/tv_mirriom_contacts">

    </FrameLayout>

    some other widgets

</androidx.constraintlayout.widget.ConstraintLayout>

在此frameLayout中，我显示了一个包含recyclerView的fragemnt。我将滚动所有布局，而不仅仅是recyclerView。所以我实现了这种结构

<androidx.constraintlayout.widget.ConstraintLayout >
<NestedScrollView>
<androidx.constraintlayout.widget.ConstraintLayout >
 <FrameLayout
       android:layout_width="0dp"
        android:layout_height="wrap_content"
 />
 Other widgets
</androidx.constraintlayout.widget.ConstraintLayout >
</NestedScrollView>
</androidx.constraintlayout.widget.ConstraintLayout >

在此模式下滚动是正确的，但是回收站的所有项目一起加载，并导致应用程序无响应

这是我的片段

<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context=".Activites.Event.Fragments.MirriomContactsFrag">


    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recycler_contact"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:scrollbars="vertical"
        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"
        tools:listitem="@layout/item_user" />



</androidx.constraintlayout.widget.ConstraintLayout>

编辑

我的片段xml：

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context=".Activites.Event.Fragments.MirriomContactsFrag">


    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recycler_contact"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:scrollbars="vertical"
        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"
        tools:listitem="@layout/item_user" />



</androidx.constraintlayout.widget.ConstraintLayout>

主要活动：

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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=".Activites.Settings.ContactsActivity">

    <androidx.core.widget.NestedScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <androidx.constraintlayout.widget.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent">



    <FrameLayout
        android:id="@+id/fl_contacts"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="5dp"
        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/tv_mirriom_contacts">

    </FrameLayout>

    <include
        android:id="@+id/app_bar"
        layout="@layout/search_appbar"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/textView27"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:onClick="deleteSyncedContactsItemClicked"
        android:padding="12dp"
        android:text="@string/delete_synced_contacts"
        android:clickable="true"
        android:background="@drawable/my_ripple"
        android:textColor="@color/colorAccent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/app_bar"
        android:focusable="true" />

    <TextView
        android:id="@+id/textView28"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:padding="12dp"
        android:text="@string/sync_contacts"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="1.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView27" />

    <TextView
        android:id="@+id/textView29"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:drawableStart="@drawable/ic_share"
        android:drawablePadding="12dp"
        android:padding="12dp"
        android:onClick="inviteFriendsToMirorimItemClicked"
        android:text="@string/invite_friends_to_mirorim"
        android:textColor="@color/colorAccent"
        android:clickable="true"
        android:background="@drawable/my_ripple"
        app:drawableTint="@color/colorAccent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="1.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView28"
        android:focusable="true" />

    <com.example.mirriom.Widget.SwitchButton
        android:id="@+id/swt_sync_contacts"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginRight="12dp"
        app:layout_constraintBottom_toBottomOf="@+id/textView28"
        app:layout_constraintEnd_toEndOf="@+id/textView28"
        app:layout_constraintTop_toBottomOf="@+id/textView27"
        app:sb_checked="true"
        app:sb_checked_color="#77d672"
        app:sb_checkline_width="56dp"
        app:sb_show_indicator="false"
        app:sb_uncheckcircle_width="26dp" />

    <TextView
        android:id="@+id/tv_mirriom_contacts"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="5dp"
        android:onClick="mirriomContactItemClicked"
        android:padding="@dimen/text_clickable_padding"
        android:text="@string/mirriom"
        android:textColor="@color/influencer_text_selection"
        android:textSize="@dimen/default_text_size"
        android:textStyle="bold"
        app:layout_constraintBottom_toTopOf="@+id/recycler_contact"
        app:layout_constraintEnd_toStartOf="@+id/tv_all_contacts"
        app:layout_constraintTop_toBottomOf="@+id/textView29" />

    <TextView
        android:id="@+id/tv_all_contacts"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="12dp"
        android:onClick="AllContactItemClicked"
        android:padding="@dimen/text_clickable_padding"
        android:text="@string/all"
        android:textColor="@color/influencer_text_selection"
        android:textSize="@dimen/default_text_size"
        android:textStyle="bold"
        app:layout_constraintBottom_toTopOf="@+id/recycler_contact"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView29" />

    <TextView
        android:id="@+id/textView30"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="12dp"
        android:text="@string/contacts"
        android:textColor="@color/text_color"
        android:textSize="@dimen/default_text_size"
        android:textStyle="bold"
        app:layout_constraintBottom_toBottomOf="@+id/tv_mirriom_contacts"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@+id/tv_mirriom_contacts" />

        </androidx.constraintlayout.widget.ConstraintLayout>
    </androidx.core.widget.NestedScrollView>

</androidx.constraintlayout.widget.ConstraintLayout>

Answer 1

您的RecyclerView的layout_height设置为wrap_content，它告诉它立即对所有项目进行充气，然后将其高度设置为项目的总高度，而无需滚动（即，滚动仅来自父级NestedScrollView）。您想将其放置在NestedScrollView之外，并将其高度设置为match_parent（如果它在0dp中，并且具有适当大小的约束，则将其设置为ConstraintLayout），这将告诉它填充可用空间。如果要使用RecyclerView嵌套滚动来折叠工具栏，请参见this question以了解如何使用CoordinatorLayout完成此操作。