Java “回收器”视图需要30秒才能加载,滚动时也会滞后
我按照本教程(“”)生成了移动存储和SD卡中可用的视频列表,但当我运行应用程序时,加载到第一个活动(即所有可用视频的列表)大约需要30秒,而且当“回收器”视图可用且我开始滚动时,滚动会很慢,请帮我解决这个问题,下面是我的应用程序代码 video_list_items.xmlJava “回收器”视图需要30秒才能加载,滚动时也会滞后,java,android,android-studio,Java,Android,Android Studio,我按照本教程(“”)生成了移动存储和SD卡中可用的视频列表,但当我运行应用程序时,加载到第一个活动(即所有可用视频的列表)大约需要30秒,而且当“回收器”视图可用且我开始滚动时,滚动会很慢,请帮我解决这个问题,下面是我的应用程序代码 video_list_items.xml <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/
<?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"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content" > <!--if you add match parent it will cause large spaces between files while scrolling-->
<android.support.v7.widget.CardView
android:id="@+id/videoCardView"
android:layout_width="match_parent"
android:layout_height="150dp"
app:cardElevation="3dp"
android:layout_gravity="center"
android:layout_margin="4dp"
app:cardUseCompatPadding="true">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:weightSum="5">
<ImageView
android:id="@+id/VideoImageView"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="4"
android:scaleType="centerCrop"
android:layout_gravity="center"/>
<TextView
android:id="@+id/VideoTextView"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:layout_margin="5dp"
android:maxLines="1"
android:text="File Name"/>
</LinearLayout>
</android.support.v7.widget.CardView>
</LinearLayout>
VideoAdapter.java
import android.content.Context;
import android.graphics.Bitmap;
import android.media.ThumbnailUtils;
import android.provider.MediaStore;
import android.support.annotation.NonNull;
import android.support.v7.widget.CardView;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import com.example.hdvideoandaudioplayer.MainActivity;
import com.example.hdvideoandaudioplayer.R;
import java.io.File;
import java.util.ArrayList;
public class VideoAdapter extends RecyclerView.Adapter<VideoViewHolder> {
private Context context;
ArrayList<File> videoArrayList;
public VideoAdapter(Context context, ArrayList<File> videoArrayList) {
this.context = context;
this.videoArrayList = videoArrayList;
}
@Override
public VideoViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View vView = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.video_list_items, viewGroup, false);
return new VideoViewHolder(vView);
}
@Override
public void onBindViewHolder(@NonNull VideoViewHolder videoViewHolder, int i) {
videoViewHolder.vTextView.setText(MainActivity.fileArrayList.get(i).getName());
Bitmap bitmapThumbnail = ThumbnailUtils.createVideoThumbnail(videoArrayList.get(i).getPath(), MediaStore.Video.Thumbnails.MINI_KIND);
videoViewHolder.vImageView.setImageBitmap(bitmapThumbnail);
}
@Override
public int getItemCount() {
if(videoArrayList.size()>0){
return videoArrayList.size();
}
else {
return 1;
}
}
}
class VideoViewHolder extends RecyclerView.ViewHolder {
TextView vTextView;
ImageView vImageView;
CardView vCardView;
public VideoViewHolder(@NonNull View itemView) {
super(itemView);
vTextView = itemView.findViewById(R.id.VideoTextView);
vImageView = itemView.findViewById(R.id.VideoImageView);
vCardView = itemView.findViewById(R.id.videoCardView);
}
}
导入android.content.Context;
导入android.graphics.Bitmap;
导入android.media.ThumbnailUtils;
导入android.provider.MediaStore;
导入android.support.annotation.NonNull;
导入android.support.v7.widget.CardView;
导入android.support.v7.widget.RecyclerView;
导入android.view.LayoutInflater;
导入android.view.view;
导入android.view.ViewGroup;
导入android.widget.ImageView;
导入android.widget.TextView;
导入com.example.hdvideoandaudioplayer.main活动;
导入com.example.hdvideoandaudioplayer.R;
导入java.io.File;
导入java.util.ArrayList;
公共类VideoAdapter扩展了RecyclerView.Adapter{
私人语境;
ArrayList视频ArrayList;
公共VideoAdapter(上下文上下文,ArrayList videoArrayList){
this.context=上下文;
this.videoArrayList=videoArrayList;
}
@凌驾
公共VideoViewHolder onCreateViewHolder(视图组视图组,int i){
View vView=LayoutInflater.from(viewGroup.getContext()).flate(R.layout.video\u list\u items,viewGroup,false);
返回新的VideoViewHolder(vView);
}
@凌驾
BindViewHolder上的公共无效(@NonNull VideoViewHolder VideoViewHolder,int i){
videoViewHolder.vTextView.setText(MainActivity.fileArrayList.get(i.getName());
位图bitmapThumbnail=ThumbnailUtils.createVideoThumbnail(videoArrayList.get(i).getPath(),MediaStore.Video.Thumbnails.MINI_KIND);
videoViewHolder.vImageView.setImageBitmap(位图缩略图);
}
@凌驾
public int getItemCount(){
如果(videoArrayList.size()>0){
返回videoArrayList.size();
}
否则{
返回1;
}
}
}
类VideoViewHolder扩展了RecyclerView.ViewHolder{
文本视图vTextView;
图像视图vImageView;
CardView vCardView;
公共VideoViewHolder(@NonNull View itemView){
超级(项目视图);
vTextView=itemView.findviewbyd(R.id.VideoTextView);
vImageView=itemView.findViewById(R.id.VideoImageView);
vCardView=itemView.findViewById(R.id.videoCardView);
}
}
activity_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"
tools:context=".MainActivity">
<android.support.v7.widget.RecyclerView
android:id="@+id/videoListRecyclerView"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</android.support.v7.widget.RecyclerView>
</LinearLayout>
MainActivity.java
package com.example.hdvideoandaudioplayer;
import android.Manifest;
import android.content.pm.PackageManager;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.Toast;
import com.example.hdvideoandaudioplayer.Adapter.VideoAdapter;
import java.io.File;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity {
RecyclerView mRecyclerView;
VideoAdapter obj_VideoAdapter;
public static int REQUEST_PERMISSION = 1;
File directory;
boolean BOOLEAN_PERMISSION;
public static ArrayList<File> fileArrayList = new ArrayList<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mRecyclerView = findViewById(R.id.videoListRecyclerView);
directory = new File("/mnt/");
GridLayoutManager gridLayoutManager = new GridLayoutManager(MainActivity.this, 2);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setItemViewCacheSize(20);
mRecyclerView.setLayoutManager(gridLayoutManager);
permissionForVideo();
}
private void permissionForVideo() {
if((ContextCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED)){
if((ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, Manifest.permission.READ_EXTERNAL_STORAGE))){
}
else {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, REQUEST_PERMISSION);
}
} else{
BOOLEAN_PERMISSION = true;
getFile(directory);
obj_VideoAdapter = new VideoAdapter(getApplicationContext(), fileArrayList);
obj_VideoAdapter.setHasStableIds(true);
mRecyclerView.setAdapter(obj_VideoAdapter);
}
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if(requestCode == REQUEST_PERMISSION){
if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
BOOLEAN_PERMISSION = true;
getFile(directory);
obj_VideoAdapter = new VideoAdapter(getApplicationContext(), fileArrayList);
mRecyclerView.setAdapter(obj_VideoAdapter);
} else{
Toast.makeText(this, "Please grant Permission", Toast.LENGTH_SHORT).show();
}
}
}
public ArrayList<File> getFile(File directory) {
File[] listFile = directory.listFiles();
if(listFile!=null && listFile.length>0){
for (File file : listFile) {
if (file.isDirectory()) {
getFile(file);
} else {
BOOLEAN_PERMISSION = false;
if (file.getName().endsWith(".mp4") || file.getName().endsWith(".m4a") || file.getName().endsWith(".m4v") || file.getName().endsWith(".f4a") || file.getName().endsWith(".f4v") || file.getName().endsWith(".mp4") || file.getName().endsWith(".m4b") || file.getName().endsWith(".m4r") || file.getName().endsWith(".mp4") || file.getName().endsWith(".f4b") || file.getName().endsWith(".mov") || file.getName().endsWith(".3gp") || file.getName().endsWith(".3gp2") || file.getName().endsWith(".3g2") || file.getName().endsWith(".3gpp") || file.getName().endsWith(".3gpp2") || file.getName().endsWith(".3gp") || file.getName().endsWith(".ogg") || file.getName().endsWith(".oga") || file.getName().endsWith(".ogv") || file.getName().endsWith(".ogx") || file.getName().endsWith(".wmv") || file.getName().endsWith(".wma") || file.getName().endsWith(".asf*") || file.getName().endsWith(".webm") || file.getName().endsWith(".flv") || file.getName().endsWith(".avi") || file.getName().endsWith(".mkv") || file.getName().endsWith(".flv") || file.getName().endsWith(".vob") || file.getName().endsWith(".drc") || file.getName().endsWith(".gif") || file.getName().endsWith(".gifv") || file.getName().endsWith(".mng") || file.getName().endsWith(".MTS") || file.getName().endsWith(".MT2S") || file.getName().endsWith(".TS") || file.getName().endsWith(".mov") || file.getName().endsWith(".qt") || file.getName().endsWith(".wmv") || file.getName().endsWith(".yuv") || file.getName().endsWith(".rm") || file.getName().endsWith(".mvb") || file.getName().endsWith(".amv") || file.getName().endsWith(".mpg") || file.getName().endsWith(".mp2") || file.getName().endsWith(".mpeg") || file.getName().endsWith(".mpe") || file.getName().endsWith(".mpv") || file.getName().endsWith(".xvi") || file.getName().endsWith(".mxf") || file.getName().endsWith(".roq") || file.getName().endsWith(".nsv") || file.getName().endsWith(".3gp")) {
for (int j = 0; j < fileArrayList.size(); j++) {
if (fileArrayList.get(j).getName().equals(file.getName())) {
BOOLEAN_PERMISSION = true;
}
}
if (BOOLEAN_PERMISSION) {
BOOLEAN_PERMISSION = false;
} else {
fileArrayList.add(file);
}
}
}
}
}
return fileArrayList;
}
}
package com.example.hdvideoandaudioplayer;
导入android.Manifest;
导入android.content.pm.PackageManager;
导入android.support.annotation.NonNull;
导入android.support.v4.app.ActivityCompat;
导入android.support.v4.content.ContextCompat;
导入android.support.v7.app.AppActivity;
导入android.os.Bundle;
导入android.support.v7.widget.GridLayoutManager;
导入android.support.v7.widget.RecyclerView;
导入android.view.view;
导入android.widget.Toast;
导入com.example.hdvideoandaudioplayer.Adapter.VideoAdapter;
导入java.io.File;
导入java.util.ArrayList;
公共类MainActivity扩展了AppCompatActivity{
回收视图mRecyclerView;
视频适配器obj_视频适配器;
公共静态int请求\ u权限=1;
文件目录;
布尔权限;
public static ArrayList fileArrayList=new ArrayList();
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mRecyclerView=findviewbyd(R.id.videolistryclerview);
目录=新文件(“/mnt/”);
GridLayoutManager GridLayoutManager=新的GridLayoutManager(MainActivity.this,2);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setItemViewCacheSize(20);
mRecyclerView.setLayoutManager(gridLayoutManager);
视频许可证();
}
私人视频无效许可证(){
if((ContextCompat.checkSelfPermission(getApplicationContext(),Manifest.permission.READ\u EXTERNAL\u STORAGE)!=PackageManager.permission\u provided)){
if((ActivityCompat.shouldShowRequestPermissionRegulation(MainActivity.this、Manifest.permission.READ\u外部存储))){
}
否则{
ActivityCompat.requestPermissions(MainActivity.this,新字符串[]{Manifest.permission.READ_EXTERNAL_STORAGE},REQUEST_permission);
}
}否则{
布尔值_权限=true;
getFile(目录);
obj_VideoAdapter=新的VideoAdapter(getApplicationContext(),fileArrayList);
obj_VideoAdapter.setHasStableIds(true);
mRecyclerView.setAdapter(obj_VideoAdapter);
}
}
@凌驾
public void onRequestPermissionsResult(int-requestCode,@NonNull-String[]permissions,@NonNull-int[]grantResults){
super.onRequestPermissionsResult(请求代码、权限、授权结果);
if(requestCode==请求权限){
if(grantResults.length>0&&grantResults[0]==PackageManager.PERMISSION\u已授予){
布尔值_权限=true;
getFile(目录);
obj_VideoAdapter=新的VideoAdapter(getApplicationContext(),fileArrayList);
mRecyclerView.setAdapter(obj_VideoAdapter);
}否则{
Toast.makeText(这是“请授予许可”,Toast.LENGTH_SHORT).show();
}
}
}
公共ArrayList getFile(文件目录){
File[]listFile=directory.listFiles();
if(listFile!=null&&listFile.length>0){
用于(文件:listFile){
if(file.isDirectory()){
implementation 'com.github.bumptech.glide:glide:3.8.0'
Glide.with(this).load(videoArrayList.get(i).
thumbnail(0.2f).into(videoViewHolder.vImageView)