FileWriter not writing to file in Android?

Question

I am trying to write to a new file named "filename.txt" and write out "hi" when I open an app. How do I go about this? I run this code in Eclipse, press F11, open up the AVD, and click on the app. I get the "Hello World, appname!" message, but no file is created.

package com.paad.comparison;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.os.Environment;
import android.widget.Toast;

public class ComparisonOfControlCreationActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
        String string1 = "Hey you";
        FileWriter fWriter;
        try{
            fWriter = new FileWriter("filename.txt", true);
            fWriter.write("hi");
            fWriter.flush();
            fWriter.close();
        } catch(Exception e) {
            e.printStackTrace();
        }

        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}

EDIT: For anyone that happens to run into this problem in the future, make sure your AndroidManifest.xml file has the following line in it:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

Answer 1

Try like this:

FileWriter fWriter;
File sdCardFile = new File(Environment.getExternalStorageDirectory() + " \filename.txt");
Log.d("TAG", sdCardFile.getPath()); //<-- check the log to make sure the path is correct.
try{
     fWriter = new FileWriter(sdCardFile, true);
     fWriter.write("hi");
     fWriter.flush();
     fWriter.close();
 }catch(Exception e){
          e.printStackTrace();
 }