Selecting a File To Load

[Andy Crowther]

Hi all, I have working code that will export a SQ Lite Database to a set file name -

public static void saveTrip() {
        Log.i("saveTrip", "trip.size " + trip.size());
        ed.putInt("tripSize", trip.size()).apply();

        tripDB.execSQL("CREATE TABLE IF NOT EXISTS trip (lat VARCHAR, lon VARCHAR, time VARCHAR, start INTEGER, stop INTEGER, stationary INTEGER)");

        tripDB.delete("trip", null, null);

        if (trip.size() > 0) {

            try {

                for (TripMarker thisTrip : trip) {

                    // change into String to be saved to the DB
                    String thisLat = Double.toString(thisTrip.location.getLatitude());
                    String thisLon = Double.toString(thisTrip.location.getLongitude());
                    String thisTime = Long.toString(thisTrip.timeStamp);
                    int startInt = (thisTrip.start)? 1 : 0;
                    int stopInt = (thisTrip.start)? 1 : 0;
                    int stationaryInt = (thisTrip.start)? 1 : 0;

                    Log.i("Saving TripMarker", thisLat + " " + thisLon + " " + thisTime);
                    tripDB.execSQL("INSERT INTO trip (lat, lon, time, start, stop, stationary) VALUES ('" + thisLat + "' , '" + thisLon + "' , '" + thisTime + "' , '" + startInt + "' , '" + stopInt + "' , '" + stationaryInt + "')");

                }

            } catch (Exception e) {

                e.printStackTrace();
                Log.i("saveTrip", "Error Saving");

            }
        }
    }

I then have working code that will load this same file back in -

public static void loadTrip() {
        int tripSize = sharedPreferences.getInt("tripSize", 0);
        Log.i("loadTrip", "size " + tripSize);

        trip.clear();

        try {

            Cursor c = tripDB.rawQuery("SELECT * FROM trip", null);

            int latIndex = c.getColumnIndex("lat");
            int lonIndex = c.getColumnIndex("lon");
            int timeIndex = c.getColumnIndex("time");
            int startIndex = c.getColumnIndex("start");
            int stopIndex = c.getColumnIndex("stop");
            int stationaryIndex = c.getColumnIndex("stationary");

            c.moveToFirst();

            do {
                Location thisLocation = new Location("51.5007292,-0.1268194");
                thisLocation.setLatitude(Double.parseDouble(c.getString(latIndex)));
                thisLocation.setLongitude(Double.parseDouble(c.getString(lonIndex)));
                Boolean start = (c.getInt(startIndex) == 1)? true : false;
                Boolean stop = (c.getInt(stopIndex) == 1)? true : false;
                Boolean stationary = (c.getInt(stationaryIndex) == 1)? true : false;
                TripMarker newMarker = new TripMarker(thisLocation, Long.parseLong(c.getString(timeIndex)), start, stop, stationary, "Loading");

                trip.add(newMarker);

            } while (c.moveToNext());

            Log.i("loadTrip", "trip.size " + trip.size());

        } catch (Exception e) {

            Log.i("LoadingDB", "Caught Error");
            e.printStackTrace();

        }
    }

What I'd like to do is name the file as it's saved, then select it from a list of .db files in the given directory.  I think the naming should be easy enough, how would I bring a file list up for the user to select from?  I think once the file is selected, the loading of the given file name should be easy enough too.

I don't need the precise code (although I wouldn't complain if you posted it) but happy enough to research commands if you can give me some tips on what I'm looking for.

Thanks!

[Andy Crowther]

How do I edit, I posted the wrong methods!?

public void exportDB() {
        Log.i("exportDB", "Starting");
        File sd = Environment.getExternalStorageDirectory();
        File data = Environment.getDataDirectory();
        FileChannel source = null;
        FileChannel destination = null;

        File dir = new File(Environment.getExternalStorageDirectory() + "/RideOutBuddy/");
//        Log.i("dir is ", "" + dir);
//        dir.mkdir();
        try {
            if (dir.mkdir()) {
                System.out.println("Directory created");
            } else {
                System.out.println("Directory is not created");
            }
        } catch (Exception e) {
            e.printStackTrace();
            Log.i("Creating Dir Error", "" + e);
        }

        String currentDBPath = "/data/com.androidandyuk.rideoutbuddy/databases/trip";
        String backupDBPath = "RideOutBuddy/Trip.db";
        File currentDB = new File(data, currentDBPath);
        File backupDB = new File(sd, backupDBPath);
        try {
            source = new FileInputStream(currentDB).getChannel();
            destination = new FileOutputStream(backupDB).getChannel();
            destination.transferFrom(source, 0, source.size());
            source.close();
            destination.close();
            Toast.makeText(this, "DB Exported!", Toast.LENGTH_LONG).show();
        } catch (IOException e) {
            e.printStackTrace();
            Toast.makeText(this, "Exported Failed!", Toast.LENGTH_LONG).show();
        }
    }

and

public void importDB() {
        Log.i("ImportDB", "Started");
        try {
            String DB_PATH = "/data/data/com.androidandyuk.rideoutbuddy/databases/trip";

            File sdcard = Environment.getExternalStorageDirectory();
            String yourDbFileNamePresentInSDCard = sdcard.getAbsolutePath() + File.separator + "RideOutBuddy/Trip.db";

            Log.i("ImportDB", "SDCard File " + yourDbFileNamePresentInSDCard);

            File file = new File(yourDbFileNamePresentInSDCard);
            // Open your local db as the input stream
            InputStream myInput = new FileInputStream(file);

            // Path to created empty db
            String outFileName = DB_PATH;

            // Opened assets database structure
            OutputStream myOutput = new FileOutputStream(outFileName);

            // transfer bytes from the inputfile to the outputfile
            byte[] buffer = new byte[1024];
            int length;
            while ((length = myInput.read(buffer)) > 0) {
                myOutput.write(buffer, 0, length);
            }

            // Close the streams
            myOutput.flush();
            myOutput.close();
            myInput.close();
        } catch (Exception e) {
            Log.i("ImportDB", "Exception Caught" + e);
        }
        loadTrip();
        viewTrip();
    }

[Paul Clapham]

Well, assuming that you're running that code in an environment where you can just pop up a dialog to ask a user to pick a file from the local machine (and not a web app or some other distributed code), then have a look at the tutorial about file choosers: How to Use File Choosers.

[Norm Radder]

I don't know that Android has a file chooser class.  I never found it and finally wrote one for myself.
I'd be very happy if there is now one available.

[Andy Crowther]

Paul Clapham wrote:Well, assuming that you're running that code in an environment where you can just pop up a dialog to ask a user to pick a file from the local machine (and not a web app or some other distributed code), then have a look at the tutorial about file choosers: How to Use File Choosers.

Yeah, it's on my Android app.  Thanks, I'll follow that tutorial when I next have some coding time :)

[Paul Clapham]

Sorry, I didn't notice that important keyword "Android".

[Andy Crowther]

Ah, lol.  So the link is not what I need?  I had a quick look, it looked like Java? (Even though the screenies were Windows)

[Paul Clapham]

Right. Check out Norm Radder's more relevant reply.

[Andy Crowther]

Norm Radder wrote:I don't know that Android has a file chooser class.  I never found it and finally wrote one for myself.
I'd be very happy if there is now one available.

So I've come round to looking at this again, having fixed all my apps to work with Oreo...  it actually looks quite easy -

private static final int CHOOSE_FILE_REQUESTCODE = 1;

   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);

       Uri selectedUri = Uri.parse(Environment.getExternalStorageDirectory().getPath() + "/AutBuddy/");
       Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
//        intent.addCategory(Intent.CATEGORY_OPENABLE);
       intent.setDataAndType(selectedUri, "*/db");
       Intent i = Intent.createChooser(intent, "File");
       startActivityForResult(i, CHOOSE_FILE_REQUESTCODE);
       

   }

   @Override
   protected void onActivityResult(int requestCode, int resultCode, Intent data) {

       switch(requestCode){
           case CHOOSE_FILE_REQUESTCODE:
               if(resultCode==-1){
                   Uri uri = data.getData();
                   String filePath = uri.getPath();
                   Toast.makeText(this, filePath,
                           Toast.LENGTH_LONG).show();
               }
               break;
       }


       super.onActivityResult(requestCode, resultCode, data);
   }

That toasts the file location, which I assume (wont get to code it into an app until tomorrow evening at the earliest) I can just slot into my app.

What I've not got working (although people say this code should do it) is have it start off in the folder that has my db files in it.  Any ideas on that?

[Norm Radder]

have it start off in the folder that has my db files in it

That is one of the side benefits of a roll-your-own file chooser - it remembers where you last looked.

         Intent intent2 = new Intent(Intent.ACTION_GET_CONTENT);
         intent2.setType("file/*");

                //  How to get String ids below???
    		intent2.putExtra("START_PATH", new File(UserWP_Folder));
    		intent2.putExtra("TYPE_FILTER",new String[]{".wps"});  // These are only ones on one line
    		intent2.putExtra(Intent.EXTRA_TITLE, "Choose file to save to");  //????? Where does this go
    		startActivityForResult(intent2, FileChosenForSave);

My app recognizes the extra values: START_PATH and TYPE_FILTER.