Android GlideApp FixedPreloadSizeProvider RecyclerViewPreloader preload scroll smooth，Java

秒速五厘米 2023-10-13 22:43 74阅读 0赞

## Android GlideApp FixedPreloadSizeProvider RecyclerViewPreloader preload scroll smooth，Java ##

##  ##

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
        <uses-permission android:name="android.permission.READ_MEDIA_IMAGES" />

<?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout 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"
        tools:context=".MainActivity">
    
        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/recycler_view"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />
    
    </RelativeLayout>

import androidx.annotation.NonNull;
    import androidx.annotation.Nullable;
    import androidx.appcompat.app.AppCompatActivity;
    import androidx.appcompat.widget.AppCompatImageView;
    import androidx.recyclerview.widget.GridLayoutManager;
    import androidx.recyclerview.widget.RecyclerView;
    
    import android.content.Context;
    import android.database.Cursor;
    import android.graphics.drawable.Drawable;
    import android.os.Bundle;
    import android.provider.MediaStore;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.TextView;
    
    import com.bumptech.glide.ListPreloader;
    import com.bumptech.glide.RequestBuilder;
    import com.bumptech.glide.integration.recyclerview.RecyclerViewPreloader;
    import com.bumptech.glide.util.FixedPreloadSizeProvider;
    
    import java.io.File;
    import java.util.ArrayList;
    import java.util.List;
    
    public class MainActivity extends AppCompatActivity {
        private GlideRequest<Drawable> fullRequest = null;
        private GlideRequest<Drawable> preloadRequest = null;
        private MAdapter mAdapter;
    
        private int PHOTO_SIZE = 180;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
    
            fullRequest = GlideApp.with(this).asDrawable().centerCrop().override(PHOTO_SIZE);
            preloadRequest = fullRequest;
    
            rePreload();
        }
    
        private void rePreload() {
            int spanCount = 5;
    
            RecyclerView rv = findViewById(R.id.recycler_view);
            GridLayoutManager layoutManager = new GridLayoutManager(this, spanCount);
            rv.setLayoutManager(layoutManager);
    
            mAdapter = new MAdapter(this);
            rv.setAdapter(mAdapter);
    
            int loadSize = 500;
            FixedPreloadSizeProvider preloadSizeProvider = new FixedPreloadSizeProvider<MyData>(PHOTO_SIZE, PHOTO_SIZE);
            MyPreloadModelProvider preloadModelProvider = new MyPreloadModelProvider();
    
            RecyclerViewPreloader<MyData> preloader = new RecyclerViewPreloader(
                    GlideApp.with(this),
                    preloadModelProvider,
                    preloadSizeProvider,
                    loadSize
            );
    
            rv.addOnScrollListener(preloader);
    
    
            new Thread(new Runnable() {
                @Override
                public void run() {
                    ArrayList<MyData> items = readAllImage(getApplicationContext());
                    runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            mAdapter.onChange(items);
                        }
                    });
                }
            }).start();
        }
    
    
        private class MyPreloadModelProvider implements ListPreloader.PreloadModelProvider<MyData> {
    
            @NonNull
            @Override
            public List<MyData> getPreloadItems(int position) {
                List<MyData> list = new ArrayList<>();
                list.add(mAdapter.items.get(position));
                return list;
            }
    
            @Nullable
            @Override
            public RequestBuilder<?> getPreloadRequestBuilder(@NonNull MyData item) {
                return preloadRequest.load(new File(item.path));
            }
        }
    
        private class MAdapter extends RecyclerView.Adapter<MyVH> {
            private Context context;
            private ArrayList<MyData> items = new ArrayList<>();
    
            public MAdapter(Context context) {
                this.context = context;
            }
    
            public void onChange(ArrayList<MyData> items) {
                this.items = items;
                notifyDataSetChanged();
            }
    
            @NonNull
            @Override
            public MyVH onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
                View view = LayoutInflater.from(context).inflate(R.layout.item, parent, false);
                ViewGroup.LayoutParams params = view.getLayoutParams();
                params.width = PHOTO_SIZE;
                params.height = PHOTO_SIZE;
                return new MyVH(view);
            }
    
            @Override
            public void onBindViewHolder(@NonNull MyVH holder, int position) {
                fullRequest.load(new File(items.get(position).path)).centerCrop().into(holder.image);
                holder.text.setText(position + "");
            }
    
            @Override
            public int getItemCount() {
                return items.size();
            }
        }
    
        private class MyVH extends RecyclerView.ViewHolder {
            public AppCompatImageView image;
            public TextView text;
    
            public MyVH(@NonNull View itemView) {
                super(itemView);
                image = itemView.findViewById(R.id.image);
                text = itemView.findViewById(R.id.text);
            }
        }
    
        private ArrayList<MyData> readAllImage(Context context) {
            ArrayList<MyData> photos = new ArrayList<>();
    
            //读取手机图片
            Cursor cursor = context.getContentResolver().query(
                    MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                    null,
                    null,
                    null,
                    null
            );
    
            int index = 0;
            while (cursor.moveToNext()) {
                //图片路径 uri
                String path = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA));
    
                //图片名称
                //val name = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DISPLAY_NAME))
    
                //图片大小
                //val size = cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Images.Media.SIZE))
    
                photos.add(new MyData(path, index++));
            }
    
            cursor.close();
    
            return photos;
        }
    
        private class MyData {
            public String path;
            public int index;
    
            public MyData(String p, int i) {
                path = p;
                index = i;
            }
        }
    }

<?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="1dp">
    
        <androidx.appcompat.widget.AppCompatImageView
            android:id="@+id/image"
            android:layout_width="80dp"
            android:layout_height="wrap_content"
            android:scaleType="centerCrop"
            android:src="@drawable/ic_launcher_background" />
    
        <TextView
            android:id="@+id/text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:text="-.-"
            android:textColor="@android:color/holo_red_dark"
            android:textSize="20dp" />
    </RelativeLayout>

import android.content.Context;
    import android.util.Log;
    
    import androidx.annotation.NonNull;
    
    import com.bumptech.glide.GlideBuilder;
    import com.bumptech.glide.annotation.GlideModule;
    import com.bumptech.glide.load.engine.cache.LruResourceCache;
    import com.bumptech.glide.module.AppGlideModule;
    
    @GlideModule
    public class MyModule extends AppGlideModule {
        private LruResourceCache mCache = new LruResourceCache(1024 * 1024 * 800);
    
        @Override
        public void applyOptions(@NonNull Context context, @NonNull GlideBuilder builder) {
            builder.setMemoryCache(mCache);
            builder.setLogLevel(Log.DEBUG);
        }
    
        @Override
        public boolean isManifestParsingEnabled() {
            return false;
        }
    }

[Android GlideApp GlideRequest FixedPreloadSizeProvider RecyclerViewPreloader，kotlin\_zhangphil的博客-CSDN博客【代码】Android Paging 3,kotlin（1）在实际的开发中，虽然Glide解决了快速加载图片的问题，但还有一个问题悬而未决：比如用户的头像，往往用户的头像是从服务器端读出的一个普通矩形图片，但是现在的设计一般要求在APP端的用户头像显示成圆形头像，那么此时虽然Glide可以加载，但加载出来的是一个矩形，如果要Glide\_android 毛玻璃圆角。《Android图片加载与缓存开源框架：Android Glide》Android Glide是一个开源的图片加载和缓存处理的第三方框架。![favicon32.ico][]https://blog.csdn.net/zhangphil/article/details/131813200][Android GlideApp GlideRequest FixedPreloadSizeProvider RecyclerViewPreloader_kotlin_zhangphil_-CSDN_Android Paging 3_kotlin_1_Glide_APP_Glide_Glide_android _Android_Android Glide_Android Glide_favicon32.ico_https_blog.csdn.net_zhangphil_article_details_131813200]

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[Android GlideApp GlideRequest FixedPreloadSizeProvider RecyclerViewPreloader_kotlin_zhangphil_-CSDN_Android Paging 3_kotlin_1_Glide_APP_Glide_Glide_android _Android_Android Glide_Android Glide_favicon32.ico_https_blog.csdn.net_zhangphil_article_details_131813200]: https://blog.csdn.net/zhangphil/article/details/131813200