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Apps Making a Simple Bluetooth Transfer App


Jul 3, 2012
Hi everybody!

I'm currently developing a simple app with the following functions:

So far I've managed to make the View Files work by viewing files and folders in the memory card, but I haven't added any function other than being able to view them.

Here is the code for the FileManager.java class, I just copied it from a site because I just wanted to test out if the code could really view files. I have yet to be able to make my own file manager code:

package com.android.bluetoothfiletransfer;

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

import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.app.Dialog;
import android.content.DialogInterface;
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;

public class FileExplore extends Activity {

	// Stores names of traversed directories
	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() + "");
	private String chosenFile;
	private static final int DIALOG_LOAD_FILE = 1000;

	ListAdapter adapter;

	public void onCreate(Bundle savedInstanceState) {



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


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

		// Checks whether path exists
		if (path.exists()) {
			FilenameFilter filter = new FilenameFilter() {
				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], R.drawable.file_icon);

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

				// Set drawables
				if (sel.isDirectory()) {
					fileList[i].icon = R.drawable.directory_icon;
					Log.d("DIRECTORY", fileList[i].file);
				} else {
					Log.d("FILE", fileList[i].file);

			if (!firstLvl) {
				Item temp[] = new Item[fileList.length + 1];
				for (int i = 0; i < fileList.length; i++) {
					temp[i + 1] = fileList[i];
				temp[0] = new Item("Up", R.drawable.directory_up);
				fileList = temp;
		} else {
			Log.e(TAG, "path does not exist");

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

				// put the image on the text view
						fileList[position].icon, 0, 0, 0);

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

				return view;


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

		public Item(String file, Integer icon) {
			this.file = file;
			this.icon = icon;

		public String toString() {
			return file;

	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) {
			builder.setTitle("Choose your file");
			builder.setAdapter(adapter, new DialogInterface.OnClickListener() {
				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
						fileList = null;
						path = new File(sel + "");


						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,
						fileList = null;

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

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

					// File picked
					else {
						// Perform action with file picked

		dialog = builder.show();
		return dialog;


All other buttons are nonfunctional. Can I ask for advice or preferably codes for the functions I'm looking for? I'm just planning to use this as a stepping stone for future apps. Thanks!
I don't quite understand what you are asking. What functionality do you wish to implement?

Basically, an app that serves as an all in one Bluetooth Suite. Allows one to:

1. View files and folders in memory card/storage
2. Move/rename/delete files
3. Pick files to put in a queue for sending
4. Sync devices within the app
5. Send queued files via Bluetooth to the paired device
6. Receive files via Bluetooth from a paired device
Upvote 0
Okay, so then you have #s 1 and 2 working in the code you posted that you took from a tutorial, correct? If so, I recommend you work on one number at a time. With that said, you will need to do some designing before you do any more coding to figure out what classes you need and how each of those classes relate to each other.
Upvote 0
Okay, so then you have #s 1 and 2 working in the code you posted that you took from a tutorial, correct? If so, I recommend you work on one number at a time. With that said, you will need to do some designing before you do any more coding to figure out what classes you need and how each of those classes relate to each other.

Okay then, I will, thanks :) So beginning with number one, maybe you could teach me the breakdown of making a proper file manager with the functions I mentioned? Although the one I have views files, the tutorial did not break down the bits and pieces of the code so I would like to actually know how each bit works to make a working file manager.
Upvote 0


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