MyPlayer MainActivity

MainActivityPlayer.java

import androidx.appcompat.app.AppCompatActivity;
import android.Manifest;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;

import com.karumi.dexter.Dexter;
import com.karumi.dexter.PermissionToken;
import com.karumi.dexter.listener.PermissionDeniedResponse;
import com.karumi.dexter.listener.PermissionGrantedResponse;
import com.karumi.dexter.listener.PermissionRequest;
import com.karumi.dexter.listener.single.PermissionListener;

import java.io.File;
import java.lang.reflect.Array;
import java.util.ArrayList;

import raf.tabiin.soulplayer.databinding.ActivityMainBinding;

public class MainActivity extends AppCompatActivity {
    ActivityMainBinding b;
    ListView listView;
    String[] items;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        b = ActivityMainBinding.inflate(getLayoutInflater());
        setContentView(b.getRoot());

        listView = b.listViewSong;

        runtimePermission();

    }

    public void runtimePermission() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
            Dexter.withContext(this).withPermission(Manifest.permission.MANAGE_EXTERNAL_STORAGE)
                    .withListener(new PermissionListener() {
                        @Override
                        public void onPermissionGranted(PermissionGrantedResponse permissionGrantedResponse) {
                            displaySongs();
                        }

                        @Override
                        public void onPermissionDenied(PermissionDeniedResponse permissionDeniedResponse) {

                        }

                        @Override
                        public void onPermissionRationaleShouldBeShown(PermissionRequest permissionRequest, PermissionToken permissionToken) {
                            permissionToken.continuePermissionRequest();
                        }
                    }).check();
        }
    }

    public ArrayList<File> findSong(File file) {
        ArrayList<File> arrayList = new ArrayList<>();
        File[] files = file.listFiles();

        for (File singleFile : files) {
            if (singleFile.isDirectory() && !singleFile.isHidden()) {
                arrayList.addAll(findSong(singleFile));
            } else if (singleFile.getName().endsWith(".mp3") || singleFile.getName().endsWith(".wav")) {
                arrayList.add(singleFile);
            }
        }
        return arrayList;
    }

    public void displaySongs() {
        final ArrayList<File> mySongs = findSong(Environment.getExternalStorageDirectory());
        items = new String[mySongs.size()];
        for (int i = 0; i < mySongs.size(); ++i) {
            items[i] = mySongs.get(i).getName().toString()
                    .replace(".mp3", "")
                    .replace(".wav", "");
        }
        /*ArrayAdapter<String> myAdapter =
                new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, items);*/

        CustomAdapter customAdapter = new CustomAdapter();

        listView.setAdapter(customAdapter);
    }

    class CustomAdapter extends BaseAdapter {
        @Override
        public int getCount() {
            return items.length;
        }

        @Override
        public Object getItem(int position) {
            return items[position];
        }

        @Override
        public long getItemId(int position) {
            return 0;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View myView = getLayoutInflater().inflate(R.layout.list_item, b.getRoot());
            TextView textSong = myView.findViewById(R.id.txtSongName);
            textSong.setSelected(true);
            textSong.setText(items[position]);

            return myView;
        }
    }

}