带有 Gridlayoutmanager 的 RecyclerView 加载和响应速度极慢

问题描述

在 recyclerview 的帮助下，我正在构建一个显示 2 列网格视图的应用。我的代码如下：

• activity_main.xml

   <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=".MainActivity">
  
   <androidx.recyclerview.widget.RecyclerView
       android:id="@+id/recycle"
       android:layout_width="match_parent"
       android:layout_height="match_parent" />
   </androidx.constraintlayout.widget.ConstraintLayout>
  

• custom_item_layout.xml

  <shape xmlns:android="http://schemas.android.com/apk/res/android">
    <!--
       stroke with color and width for creating outer line
    -->
    <stroke
        android:width="5dp"
        android:color="#DBE2E9" />
  </shape>
  

• row_layout.xml

   <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="wrap_content"
    android:layout_height="180dp"
    android:background="@drawable/custom_item_layout"
    android:padding="5dp">
    <!--
    grid items for RecyclerView
    -->
    <ImageView
        android:id="@+id/image"
        android:layout_width="180dp"
        android:layout_height="180dp"
        android:layout_marginStart="5dp"
        android:layout_marginTop="5dp"
        android:layout_marginEnd="5dp"
        android:scaleType="centerCrop"
        android:src="@mipmap/ic_launcher"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
  
    </androidx.constraintlayout.widget.ConstraintLayout>
  

• MainActivity.java

   public class MainActivity extends AppCompatActivity {
  
    // ArrayList for all app genres
    ArrayList appNames = new ArrayList<>(Arrays.asList( "Augmented reality","Beauty","Books & Reference","Comics","Communication","Dating","Entertainment","Food & Drink","Games","Kids","Music & Audio","Photography","Social","Video Players & Editors"));
    ArrayList appImages = new ArrayList<>(Arrays.asList(R.drawable.a_r,R.drawable.beauty,R.drawable.ic_books,R.drawable.ic_smashing_book_icon_comic_book_icon_11553392583tcjc,R.drawable.comms,R.drawable.date,R.drawable.entertainment,R.drawable.foods,R.drawable.games,R.drawable.kids,R.drawable.music,R.drawable.camera,R.drawable.social,R.drawable.video));
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // get the reference of RecyclerView
        RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycle);
        // set a GridLayoutManager with default vertical orientation and 2 number of columns
        GridLayoutManager gridLayoutManager = new GridLayoutManager(getApplicationContext(),2);
        recyclerView.setLayoutManager(gridLayoutManager); // set LayoutManager to RecyclerView
        //  call the constructor of CustomAdapter to send the reference and data to Adapter
        CustomAdapter customAdapter = new CustomAdapter(MainActivity.this,appNames,appImages);
        recyclerView.setAdapter(customAdapter); // set the Adapter to RecyclerView
    }
  }
  

• CustomAdapter.java

   public class CustomAdapter extends RecyclerView.Adapter {
  
    ArrayList appNames;
    ArrayList appImages;
    Context context;
    boolean allowed = false;
    LottieAlertDialog.Builder alert;
    public CustomAdapter(Context context,ArrayList appNames,ArrayList appImages) {
        this.context = context;
        this.appNames = appNames;
        this.appImages = appImages;
    }
    @NonNull
    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent,int viewType) {
        // infalte the item Layout
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_layout,parent,false);
        // set the view's size,margins,paddings and layout parameters
        return new MyViewHolder(v);
    }
  
    @Override
    public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder,int position) {
        MyViewHolder mholder=(MyViewHolder) holder;
        mholder.image.setimageResource((Integer) appImages.get(position));  
    }
  
    @Override
    public int getItemCount() {
        return appNames.size();
    }
    public static class MyViewHolder extends RecyclerView.ViewHolder {
        public ImageView image;
        public MyViewHolder(View itemView) {
            super(itemView);
            this.image = (ImageView) itemView.findViewById(R.id.image);
        }
    }
  }
  

我所有的矢量资源都是大小：

android:width="512dp"
android:height="512dp"
android:viewportWidth="512"
android:viewportHeight="512">

问题是，当我运行应用程序时，加载时间很长，并且设备一直冻结。我不知道为什么会这样。我该如何解决这个问题？

解决方法

使用 Glide 等图像处理库将图像加载到 imageview 中。这可能有帮助