Load a Text File

Question

I'm currently trying to write a program that can load a selected text file from internal/external storage for use in an Android application.

I've already tried loading the file using the following code via this page to no avail:

File sdcard = Environment.getExternalStorageDirectory();
File file = new File(sdcard,"file.txt");

and this (thanks to Google)

public void performFileSearch() {
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.setType("text/plain");
startActivityForResult(intent, READ_REQUEST_CODE);
}

@Override
public void onActivityResult(int requestCode, int resultCode,
                             Intent resultData) {
    super.onActivityResult(requestCode, resultCode, resultData);
    if (requestCode == READ_REQUEST_CODE && resultCode == Activity.RESULT_OK) {
        Uri uri = null;
        if (resultData != null) {
            uri = resultData.getData();
            Log.i(TAG, "Uri: " + uri.getPath());
            File file = new File(uri.getPath());
            if (file.exists()) {
                Log.i(TAG, "Exists");
            } else {
                Log.i(TAG, "Does not exist");
            }
        }
    }
}

In the later case, (where the user selects a text file) when a text file is selected it surprisingly returns false. I also get similar errors for the first block of code. I read that you can load a file from a uri using an InputStream, but I don't know how to implement this. Thanks for any and all the help.

score 0 · Answer 1 · 2019-09-16T12:10:24.027

File file = new File(sdcard,"file.txt");

don't mean file is there. You check it, the data read it like.

    File sdcard = Environment.getDataDirectory();
    File file = new File(sdcard,"file.txt");
    if (file.exists()) {
        InputStream readData;
        byte[] buffer = new byte[4096];
        int readLength;
        try {
            readData = new FileInputStream(file);
            while ((readLength = readData.read(buffer)) > 0) {
                // do work here to data
                // readLength 4096 not always, last not as much often
            }
            readData.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    } else {
        // do nothing file exist
    }

must have set the permisssions to create if not exception will happen.

many ways of data reading

Hi, thanks for the response. I've tried your code, and it says that the file exists, but it's still showing that the file cannot be read. Any suggestions? — Alex S, Sep 16 '19 at 21:19

Load a Text File

1 Answers1