File Chooser Dialog for Android

FileChooserDialog.java

import android.app.Dialog;
import android.content.Context;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.content.ContextCompat;
import android.util.Log;
import android.view.ActionMode;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Random;

/**
 * Created by satyasnehith on 3/10/17.
 */
class FileChooserDialog extends Dialog {
    private TextView pTextView;
    private ListView fListView;
    private String path;
    private ImageButton imageButton;
    private Button cButton, sButton;
    private Context context;
    private ArrayList<File> fileArrayList;
    private ArrayList<File> selectedFiles;
    private File[] files;
    private File file;
    boolean longClick = false;
    private FileArrayAdapter adapter;
    private FileChooserListener fileChooserListener;
    final String CLEAR = "Clear";
    private int[] icons = {
            R.drawable.black,
            R.drawable.blue,
            R.drawable.brown,
            R.drawable.dblue,
            R.drawable.green,
            R.drawable.grey,
            R.drawable.kgreen,
            R.drawable.lblue,
            R.drawable.lyellow,
            R.drawable.maroon,
            R.drawable.red,
            R.drawable.vkgreen,
            R.drawable.vpink,
            R.drawable.yellow,

    };
    public FileChooserDialog(@NonNull Context context) {
        super(context);
        this.context = context;
    }
    public void fileChooserListener(FileChooserListener fileChooserListener){
        this.fileChooserListener = fileChooserListener;
    }
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.dialog_file_chooser);
        path = "/storage/emulated/0/";
        pTextView = findViewById(R.id.path);
        pTextView.setText(path);
        imageButton = findViewById(R.id.ib_back);
        imageButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                longClick = false;
                if (path.equals("/storage/emulated/0/")) {
                } else {
                    clearChoices();
                    if (path.equals("") || path.equals(null))
                        dismiss();
                    String[] split = path.split("/");
                    path = "";
                    for (int i = 0; i < split.length - 1; ++i) {
                        path = path + split[i] + "/";
                    }
                    file = new File(path);
                    pTextView.setText(path);
                    files = file.listFiles();
                    fileArrayList.clear();
                    try {
                        for (File s : files) {
                            fileArrayList.add(s);
                        }
                    } catch (NullPointerException e) {
                        e.printStackTrace();
                    }
                    updateChecks();
                    adapter.notifyDataSetChanged();
                    cButton.setText(CLEAR +" (" +selectedFiles.size() + ")");
                }
            }
        });
        cButton = findViewById(R.id.btn_clear);
        cButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                clearChoices();
            }
        });
        sButton = findViewById(R.id.btn_send);
        sButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                fileChooserListener.onFileChoosen(selectedFiles.toArray(new File[selectedFiles.size()]));
            }
        });
        fileArrayList = new ArrayList<>();
        selectedFiles = new ArrayList<>();
        file = new File(path);
        files = file.listFiles();
        for (File s : files) {
            fileArrayList.add(s);
        }
        adapter = new FileArrayAdapter(context);
        fListView = findViewById(R.id.files_list);
        fListView.setAdapter(adapter);
        fListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                if(selectedFiles.isEmpty())
                    longClick = false;
                if(longClick) {
                    ImageView imageView = view.findViewById(R.id.iv_check);
                    if (imageView.getVisibility() == View.VISIBLE) {
                        imageView.setVisibility(View.INVISIBLE);
                        selectedFiles.remove(fileArrayList.get(i));
                        cButton.setText(CLEAR + " (" + selectedFiles.size() + ")");
                    } else {
                        imageView.setVisibility(View.VISIBLE);
                        selectedFiles.add(fileArrayList.get(i));
                        cButton.setText(CLEAR + " (" + selectedFiles.size() + ")");
                    }
                    adapter.getView(i, view, fListView);
                } else {
                    if (path.equals("") || path.equals(null)) {
                        dismiss();
                    }
                    String p = path + fileArrayList.get(i).getName() + "/";
                    file = new File(p);
                    if (file.isDirectory()) {
                        path = p;
                        pTextView.setText(path);
                        files = file.listFiles();
                        fileArrayList.clear();
                        for (File s : files) {
                            fileArrayList.add(s);
                        }
                        adapter.notifyDataSetChanged();

                    } else {
                        ImageView imageView = view.findViewById(R.id.iv_check);
                        if (imageView.getVisibility() == View.VISIBLE) {
                            imageView.setVisibility(View.INVISIBLE);
                            selectedFiles.remove(fileArrayList.get(i));
                            cButton.setText(CLEAR + " (" + selectedFiles.size() + ")");
                        } else {
                            imageView.setVisibility(View.VISIBLE);
                            selectedFiles.add(fileArrayList.get(i));
                            cButton.setText(CLEAR + " (" + selectedFiles.size() + ")");
                        }
                        adapter.getView(i, view, fListView);
                    }
                }
            }
        });
        fListView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
                longClick = true;
                ImageView imageView = view.findViewById(R.id.iv_check);
                if(imageView.getVisibility() == View.VISIBLE) {
                    imageView.setVisibility(View.INVISIBLE);
                    selectedFiles.remove(fileArrayList.get(position));
                    cButton.setText(CLEAR +" (" +selectedFiles.size() + ")");
                } else  {
                    imageView.setVisibility(View.VISIBLE);
                    selectedFiles.add(fileArrayList.get(position));
                    cButton.setText(CLEAR +" (" +selectedFiles.size() + ")");
                }
                adapter.getView(position, view, fListView);
                return true;
            }
        });
    }
    public void updateChecks() {

    }
    public void clearChoices() {
        selectedFiles.clear();
    }
    public interface FileChooserListener {
        public void onFileChoosen(File[] files);
    }
    class FileArrayAdapter extends ArrayAdapter<File> {

        public FileArrayAdapter(@NonNull Context context) {
            super(context, R.layout.file);
        }

        @Override
        public int getCount() {
            return fileArrayList.size();
        }

        @Nullable
        @Override
        public File getItem(int position) {
            return fileArrayList.get(position);
        }

        @NonNull
        @Override
        public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
            ViewHolder viewHolder;
            View view = convertView;
            if(view == null) {
                viewHolder = new ViewHolder();
                LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                view = inflater.inflate(R.layout.file, parent, false);
                viewHolder.imageView = view.findViewById(R.id.image);
                viewHolder.eTextView = view.findViewById(R.id.extension);
                viewHolder.nTextView = view.findViewById(R.id.file_name);
                viewHolder.tTextView = view.findViewById(R.id.file_type);
                viewHolder.cImageView = view.findViewById(R.id.iv_check);
                view.setTag(viewHolder);
            }
            File file = getItem(position);
            viewHolder = (ViewHolder) view.getTag();
            viewHolder.nTextView.setText(file.getName());
            if(file.isDirectory()) {
                viewHolder.imageView.setImageResource(R.drawable.dir);
                viewHolder.tTextView.setText("Directory");
                viewHolder.eTextView.setText("");
            } else if(file.isHidden()) {
                viewHolder.imageView.setImageResource(R.drawable.black);
                viewHolder.tTextView.setText("hidden file");
                viewHolder.eTextView.setText("HIDE");
            } else if(file.isFile()) {
                String extension = getExtension(file.getName()).toUpperCase();
                Random random = new Random();
                int r = random.nextInt(13) + 1;
                viewHolder.imageView.setImageResource(icons[r]);
                viewHolder.tTextView.setText(extension + " file");
                if(extension.length() < 4)
                    viewHolder.eTextView.setTextSize(10);
                else if(extension.length() < 5)
                    viewHolder.eTextView.setTextSize(8);
                else if(extension.length() < 8)
                    viewHolder.eTextView.setTextSize(5);
                else if (extension.length() > 7) {
                    extension = extension.substring(0, 7);
                    viewHolder.eTextView.setTextSize(5);
                }
                viewHolder.eTextView.setText(extension);
            }
            if(selectedFiles.contains(file)) {
                viewHolder.cImageView.setVisibility(View.VISIBLE);
            } else {
                viewHolder.cImageView.setVisibility(View.INVISIBLE);
            }
            return view;
        }
        private String getExtension(String name) {
            String[] split = name.split("\\.");
            return split[split.length-1];
        }
    }
    static class ViewHolder {
        ImageView imageView;
        TextView nTextView, tTextView, eTextView;
        ImageView cImageView;
    }
}