Files copied by my app not showing up on PC

Question

I'm trying to run a simple database backup in my application, but the files are not showing up when I connect the device to my PC, but appears to be OK in the Android File Manager. The file is being copied to "Downloads" folder by the way...

Here is the code I'm running to copy it:

//...
private void backupDatabase(){

    String downloadsPath = Environment
            .getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS)
            .getAbsolutePath();
    String backupDirectoryPath = downloadsPath+"/myapp_backups/";
    File backupDirectory = new File(backupDirectoryPath);
    backupDirectory.mkdirs();

    String bkpFileName = "backup_"+(new Date().getTime())+".bkp";

    String src = mContext.getDatabasePath(DatabaseHelper.DATABASE_NAME).getAbsolutePath();
    String dest = backupDirectoryPath + bkpFileName;
    FileUtil.copyFile(src, dest);

}
//...

And here what FileUtil.copyFile function looks like:

public static boolean copyFile(String src, String dest){

    boolean success;

    try{
        if(!isFile(src)){
            throw new Exception("Source file doesn't exist: "+src);
        }

        InputStream in = new FileInputStream(src);
        OutputStream out = new FileOutputStream(dest);

        // Transfer bytes from in to out
        byte[] buf = new byte[1024];
        int len;
        while ((len = in.read(buf)) > 0) {
            out.write(buf, 0, len);
        }
        in.close();
        out.close();

        success = true;
    }catch (Exception exception){
        exception.printStackTrace();
        success = false;
    }

    return success;

}

The code works on both devices we tested but none shows the file on the PC.

What I'm missing?

Mutiny

#32789657 – Cleisthenes

Thank you @CommonsWare, I will have a look – Mutiny

Tried restarting the devices? – Odalisque

@andre3wap Yes. And both are using MTP mode – Mutiny

the easier way to see if the issue is the MTP connection with PC or the code copying the file is to on terminal type adb shell, cd mnt/sdcard/Download/ and ls. You can even use the terminal window inside AndroidStudio. That way you'll be reading directly from the file system. (adjust the directory appropriately). – Lully

@Lully thanks for your comment. It works, but I simply cant expect to a final user to know how to use ADB console =/ – Mutiny

I agree with you. I commented that as a debug tool for you to identify the real issue. For a final user point of view I would suggest you to directly launch an e-mail Intent with the DB file attached to it. So it can be send directly to you. – Lully

Answer 1

As pointed out in the question linked by @CommonsWare, I made a little research about MediaScannerConnection class and it solved the problem.

Here is the final code:

String downloadsPath = Environment
        .getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS)
        .getAbsolutePath();
String backupDirectoryPath = downloadsPath+"/myapp_backups/";
File backupDirectory = new File(backupDirectoryPath);
backupDirectory.mkdirs();

String bkpFileName = "backup_"+(new Date().getTime())+".bkp";

String src = mContext.getDatabasePath(DatabaseHelper.DATABASE_NAME).getAbsolutePath();
String dest = backupDirectoryPath + bkpFileName;
FileUtil.copyFile(src, dest);

//Scan the new file, so it will show up in the PC file explorer:
MediaScannerConnection.scanFile(
    mContext, new String[]{dest}, null, null
);

Mutiny