RecyclerView 不在两端渲染卡片项目

如何解决RecyclerView 不在两端渲染卡片项目

我想使用 RecyclerView 水平显示用户卡片，但我遇到了如下图所示的问题。

卡片一开始没有出现，但是当我稍微滚动它时，卡片突然出现。看起来真的很奇怪。为什么不从一开始就渲染卡片？ RecyclerView 的另一端也是同样的情况。

我怀疑是 clipChildren 或 clipToPadding。有没有办法解决这个问题，而不必将类别放在带有填充的 LinearLayout 之外？

HomeFragment.kt

class HomeFragment : Fragment() {
    private lateinit var binding: FragmentHomeBinding

    override fun onCreateView(
        inflater: LayoutInflater,container: ViewGroup?,savedInstanceState: Bundle?
    ): View? {
        binding = FragmentHomeBinding.inflate(inflater,container,false)
        val view = binding.root

        setupCategories()
        setupProducts()
        return view
    }

    override fun onViewCreated(view: View,savedInstanceState: Bundle?) {
        super.onViewCreated(view,savedInstanceState)
    }

    private fun setupCategories() {
        val dummy = arrayOf(
            Category(R.drawable.shoes_nike_black),Category(R.drawable.yellow_shirt),Category(R.drawable.hoodie_gray_big),Category(R.drawable.hoodie_pink),)
        val spacingInPixels = (Resources.getSystem().displayMetrics.density * 8).toInt()
        binding.includeContentMain.recyclerViewCategories.addItemdecoration(
            LinearSpacingItemdecoration(spacingInPixels)
        )
        binding.includeContentMain.recyclerViewCategories.adapter = CategoriesAdapter(dummy)
    }

    // other unrelated code...
}

content_main.xml

<?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="match_parent"
    android:clipChildren="false"
    android:clipToPadding="false"
    android:orientation="vertical"
    android:paddingLeft="25dp"
    android:paddingTop="15dp"
    android:paddingRight="30dp"
    android:paddingBottom="15dp"
    tools:showIn="@layout/fragment_home">

    <TextView
        android:id="@+id/textViewCategory"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="25dp"
        android:layout_marginBottom="12dp"
        android:text="Category"
        android:textSize="30dp" />

    <androidx.core.widget.nestedScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:clipChildren="false"
        android:clipToPadding="false"
        android:fillViewport="true">

        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/recyclerViewCategories"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:clipChildren="false"
            android:clipToPadding="false"
            android:nestedScrollingEnabled="false"
            android:orientation="horizontal"
            android:overScrollMode="always"
            app:layoutManager="androidx.recyclerview.widget.linearlayoutmanager"
            tools:itemCount="4"
            tools:listitem="@layout/item_card_category" />
    </androidx.core.widget.nestedScrollView>

    <TextView
        android:id="@+id/textView3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="25dp"
        android:layout_marginBottom="12dp"
        android:text="Top Selling"
        android:textSize="30dp" />

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recyclerViewTopSelling"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:isScrollContainer="false"
        app:layoutManager="androidx.recyclerview.widget.GridLayoutManager"
        app:spanCount="2"
        tools:itemCount="6"
        tools:listitem="@layout/item_card_product">

    </androidx.recyclerview.widget.RecyclerView>

</LinearLayout>

item_card_category.xml

<?xml version="1.0" encoding="utf-8"?>

<androidx.cardview.widget.CardView 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="150dp"
    android:layout_height="150dp"
    app:cardBackgroundColor="#F7BE30"
    app:cardCornerRadius="10dp">

        <ImageView
            android:id="@+id/imageViewCategory"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:adjustViewBounds="true"
            android:cropToPadding="false"
            android:padding="10dp"
            android:src="@drawable/bag"
            tools:src="@tools:sample/backgrounds/scenic" />

</androidx.cardview.widget.CardView>

解决方法

这行代码会有所帮助。对于 JAVA 和 KOTLIN 使用：

recyclerViewCategories.getRecycledViewPool().setMaxRecycledViews(0,0);

*recyclerViewCategories = recyclerView