Question

I am attempting to save an array of longs as a text file using the Android’s internal memory, and then access that array in a different activity. After noticing that was broken, I isolated the problem in this chunk of code below.

long[] timings = {200, 400, 600, 1400};
try {
    FileOutputStream fos = openFileOutput("timings", Context.MODE_PRIVATE);
    OutputStreamWriter osw = new OutputStreamWriter(fos);
    osw.write(Arrays.toString(timings));        
    osw.close();

    FileInputStream fis = openFileInput("timings");
    InputStreamReader isReader = new InputStreamReader(fis);
    char[] buffer = new char[timings.length];
    isReader.read(buffer);

    textField.setText(Arrays.toString(buffer));

    fis.close();
} catch (IOException e1) {
    e1.printStackTrace();
}

The text field that is set to display what is read from the file has the following result:

[[,2,0,0]

The result I expected was the original array from above. What am I doing wrong here? Any help or advice would be appreciated.

Answer 1

Replace this :

        InputStreamReader isReader = new InputStreamReader(fis);
        char[] buffer = new char[timings.length];
        isReader.read(buffer);

        textField.setText(Arrays.toString(buffer));

with this :

        DataInputStream in = new DataInputStream(fis);
        BufferedReader br = new BufferedReader(new InputStreamReader(in));
        String sTemp1 = "", sTemp2 = "";
        while ((sTemp1 = br.readLine()) != null) {
            sTemp2 = sTemp1;
        }
        in.close();

        textField.setText(sTemp2);

I hope it will help you.