Android Apps Development: External Memory in Android

FilesActivity.Java

package com.example.files;

import android.app.Activity;

import android.os.Bundle;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.TextView;

import android.widget.Toast;

public class FilesActivity extends Activity {

EditText fname,fcontent,fnameread;

Button write,read;

TextView filecon;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_files);

fname = (EditText)findViewById(R.id.fname);

fcontent = (EditText)findViewById(R.id.ftext);

fnameread = (EditText)findViewById(R.id.fnameread);

write = (Button)findViewById(R.id.btnwrite);

read = (Button)findViewById(R.id.btnread);

filecon = (TextView)findViewById(R.id.filecon);

write.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View arg0) {

// TODO Auto-generated method stub

String filename = fname.getText().toString();

String filecontent = fcontent.getText().toString();

FileOperations fop = new FileOperations();

fop.write(filename, filecontent);

if(fop.write(filename, filecontent)){

Toast.makeText(getApplicationContext(), filename+".txt created", Toast.LENGTH_SHORT).show();

}else{

Toast.makeText(getApplicationContext(), "I/O error", Toast.LENGTH_SHORT).show();

}

});

read.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View arg0) {

// TODO Auto-generated method stub

String readfilename = fnameread.getText().toString();

FileOperations fop = new FileOperations();

String text = fop.read(readfilename);

if(text != null){

filecon.setText(text);

}

else {

Toast.makeText(getApplicationContext(), "File not Found", Toast.LENGTH_SHORT).show();

filecon.setText(null);

}

});

}

FileOperations.Java

package com.example.files;

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.File;

import java.io.FileReader;

import java.io.FileWriter;

import java.io.IOException;

import android.util.Log;

public class FileOperations {

public FileOperations() {

}

public Boolean write(String fname, String fcontent){

try {

String fpath = "/sdcard/"+fname+".txt";

File file = new File(fpath);

// If file does not exists, then create it

if (!file.exists()) {

file.createNewFile();

}

FileWriter fw = new FileWriter(file.getAbsoluteFile());

BufferedWriter bw = new BufferedWriter(fw);

bw.write(fcontent);

bw.close();

Log.d("Suceess","Sucess");

return true;

} catch (IOException e) {

e.printStackTrace();

return false;

}

public String read(String fname){

BufferedReader br = null;

String response = null;

try {

StringBuffer output = new StringBuffer();

String fpath = "/sdcard/"+fname+".txt";

br = new BufferedReader(new FileReader(fpath));

String line = "";

while ((line = br.readLine()) != null) {

output.append(line +"n");

}

response = output.toString();

} catch (IOException e) {

e.printStackTrace();

return null;

}

return response;

}

Activity_files.XML

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:orientation="vertical"

android:layout_gravity="center"

tools:context=".MainActivity" >

<TextView