FileSelectorActivity.java

//This activity will activate when a button is pressed, it will open a list that
//shows all the files in a specified directory. For now that directory is set to
//Environment.getExternalStorageDirectory().getAbsolutePath() + "/LuperApp/"
//
//the code is a modified version of this websites tutorial:
//http://thinkndoawesome.blogspot.com/2012/05/custom-media-player-on-android.html
//Created by: Cam 3/28/13

package com.teamluper.luper;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.app.Dialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListAdapter;
import android.widget.TextView;

import java.io.File;
import java.io.FilenameFilter;
import java.util.ArrayList;

//import com.teamluper.LuperApp.R;

public class FileSelectorActivity extends Activity {
 ArrayList<String> str = new ArrayList<String>();

 // Check if the first level of the directory structure is the one showing
 private Boolean firstLvl = true;

 private static final String TAG = "F_PATH";

 private Item[] fileList;
 private File path = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/LuperApp/");
 private String chosenFile;
 private static final int DIALOG_LOAD_FILE = 1000;

 ListAdapter adapter;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  // TODO Auto-generated method stub
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_file_selector);

  loadFileList();

  showDialog(DIALOG_LOAD_FILE);
  Log.d(TAG, path.getAbsolutePath());

 }

 private void loadFileList() {
  try {
   path.mkdirs();
  } catch (SecurityException e) {
   Log.e(TAG, "unable to write on the sd card ");
  }

  // Checks whether path exists
  if (path.exists()) {

   // create a filter that helps to look for files directories and
   // hidden files
   FilenameFilter filter = new FilenameFilter() {
    @Override
    public boolean accept(File dir, String filename) {
     File sel = new File(dir, filename);
     // Filters based on whether the file is hidden or not
     return (sel.isFile() || sel.isDirectory())
       && !sel.isHidden();
    }
   };

   String[] fList = path.list(filter);
   fileList = new Item[fList.length];
   for (int i = 0; i < fList.length; i++) {
    fileList[i] = new Item(fList[i]);

    // Convert into file path
    File sel = new File(path, fList[i]);
   }
  }

  else {
   Log.e(TAG, "path does not exist");
  }

  adapter = new ArrayAdapter<Item>(this,
    android.R.layout.select_dialog_item, android.R.id.text1,
    fileList) {
   @Override
   public View getView(int position, View convertView, ViewGroup parent) {
    // creates view
    View view = super.getView(position, convertView, parent);
    TextView textView = (TextView) view
      .findViewById(android.R.id.text1);

    // add margin between image and text (support various screen
    // densities)
    int dp5 = (int) (5 * getResources().getDisplayMetrics().density + 0.5f);
    textView.setCompoundDrawablePadding(dp5);

    return view;
   }
  };

 }

 private class Item {
  public String file;
  //public int icon;

  public Item(String file) {
   this.file = file;
   //this.icon = icon;
  }

  @Override
  public String toString() {
   return file;
  }
 }

 @Override
 protected Dialog onCreateDialog(int id) {
  Dialog dialog = null;
  AlertDialog.Builder builder = new Builder(this);

  if (fileList == null) {
   Log.e(TAG, "No files loaded");
   dialog = builder.create();
   return dialog;
  }

  switch (id) {
  case DIALOG_LOAD_FILE:
   builder.setTitle("Browse your file");
   builder.setAdapter(adapter, new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int which) {
     chosenFile = fileList[which].file;
     File sel = new File(path + "/" + chosenFile);
     if (sel.isDirectory()) {
      firstLvl = false;

      // Adds chosen directory to list
      str.add(chosenFile);
      fileList = null;
      path = new File(sel + "");

      loadFileList();
      // refresh the list being shown
      removeDialog(DIALOG_LOAD_FILE);
      showDialog(DIALOG_LOAD_FILE);

      Log.d(TAG, path.getAbsolutePath());
     }

     // Checks if 'up' was clicked
     else if (chosenFile.equalsIgnoreCase("up") && !sel.exists()) {

      // present directory removed from list
      String s = str.remove(str.size() - 1);

      // path modified to exclude present directory
      path = new File(path.toString().substring(0,
        path.toString().lastIndexOf(s)));
      fileList = null;

      // if there are no more directories in the list, then
      // its the first level
      if (str.isEmpty()) {
       firstLvl = true;
      }
      loadFileList();

      removeDialog(DIALOG_LOAD_FILE);
      showDialog(DIALOG_LOAD_FILE);
      Log.d(TAG, path.getAbsolutePath());

     }
     // File picked.......supposed to return fileName chosen by
     // the User
     else {
      // Perform action with file picked
      Intent intent = getIntent();
      String returnVal = path.getPath() + "/" + chosenFile;
      intent.putExtra("fileChosen", returnVal);
      setResult(RESULT_OK, intent);
      // for purpose of testing
      // Toast.makeText(getBaseContext(),
      // returnVal,Toast.LENGTH_LONG).show();
      finish();
     }
    }
   });
   break;
  }

  dialog = builder.show();
  return dialog;
 }
}