Question

how would i go about adding an entry number at the start of a saved line of text to a .txt file. eg.

• 01, entry one
• 02, entry two
• 03, entry three

and so on

here is my code to write to the file

public void onClick(View v) {try {
            BufferedWriter out = new BufferedWriter(new       FileWriter("/sdcard/input_data.txt", true));
            out.write(txtData.getText() + "," + dateFormat.format(new Date()));
            out.close();

Answer 1

Have a counter field in your object, write its value each time an entry is written, and then increment it:

private int entryCounter = 1;

public void onClick(View v) {
    try {
        BufferedWriter out = new BufferedWriter(new FileWriter("/sdcard/input_data.txt", true));
        out.write(counter + ", " + txtData.getText() + "," + dateFormat.format(new Date()));
        entryCounter++;
    ...

You should always close the writer in a finally block, to make sure it’s closed even if some exception is thrown.