create directory , read & write file in sd card

FileDemo2.java
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package com.javasamples;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class FileDemo2 extends Activity {
// GUI controls
EditText txtData;
Button btnWriteSDFile;
Button btnReadSDFile;
Button btnClearScreen;
Button btnClose;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// bind GUI elements with local controls
txtData = (EditText) findViewById(R.id.txtData);
txtData.setHint("Enter some lines of data here...");

btnWriteSDFile = (Button) findViewById(R.id.btnWriteSDFile);
btnWriteSDFile.setOnClickListener(new OnClickListener() {

public void onClick(View v) {
// write on SD card file data in the text box
try {
 
   File testDir= new File("/sdcard/TestDir/");
   // have the object build the directory structure, if needed.
   testDir.mkdirs();
 
 
File myFile = new File("/sdcard/TestDir/mysdfile.txt");
myFile.createNewFile();
FileOutputStream fOut = new FileOutputStream(myFile);
OutputStreamWriter myOutWriter =
new OutputStreamWriter(fOut);
myOutWriter.append(txtData.getText());
myOutWriter.close();
fOut.close();
Toast.makeText(getBaseContext(),
"Done writing SD 'mysdfile.txt'",
Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
}// onClick
}); // btnWriteSDFile

btnReadSDFile = (Button) findViewById(R.id.btnReadSDFile);
btnReadSDFile.setOnClickListener(new OnClickListener() {

public void onClick(View v) {
// write on SD card file data in the text box
try {
File myFile = new File("/sdcard/TestDir/mysdfile.txt");
FileInputStream fIn = new FileInputStream(myFile);
BufferedReader myReader = new BufferedReader(
new InputStreamReader(fIn));
String aDataRow = "";
String aBuffer = "";
while ((aDataRow = myReader.readLine()) != null) {
aBuffer += aDataRow + "\n";
}
txtData.setText(aBuffer);
myReader.close();
Toast.makeText(getBaseContext(),
"Done reading SD 'mysdfile.txt'",
Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
}// onClick
}); // btnReadSDFile

btnClearScreen = (Button) findViewById(R.id.btnClearScreen);
btnClearScreen.setOnClickListener(new OnClickListener() {

public void onClick(View v) {
// clear text box
txtData.setText("");
}
}); // btnClearScreen

btnClose = (Button) findViewById(R.id.btnClose);
btnClose.setOnClickListener(new OnClickListener() {

public void onClick(View v) {
// clear text box
finish();
}
}); // btnClose

}// onCreate

}// AndSDcard
///////////////////////////////////////////////////////////////////////////////



main.xml
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///////////////////////////////////////////////////////////////////////////////
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
android:id="@+id/widget28"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#ff0000ff"
android:orientation="vertical"
xmlns:android="http://schemas.android.com/apk/res/android"
>
<EditText
android:id="@+id/txtData"
android:layout_width="fill_parent"
android:layout_height="180px"
android:textSize="18sp"  />

<Button
    android:id="@+id/btnWriteSDFile"
    android:layout_width="143px"
    android:layout_height="wrap_content"
    android:text="1. Write SD File" />

<Button
    android:id="@+id/btnClearScreen"
    android:layout_width="141px"
    android:layout_height="wrap_content"
    android:text="2. Clear Screen" />

<Button
    android:id="@+id/btnReadSDFile"
    android:layout_width="140px"
    android:layout_height="wrap_content"
    android:text="3. Read SD File" />

<Button
    android:id="@+id/btnClose"
    android:layout_width="141px"
    android:layout_height="wrap_content"
    android:text="4. Close" />

</LinearLayout>

///////////////////////////////////////////////////////////////////////////////




mainifest.xml
----------------------------------------------------

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.javasamples"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk android:minSdkVersion="7" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

    <application
     
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name" >
        <activity
         
            android:label="@string/app_name"
            android:name=".FileDemo2" >
            <intent-filter >
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
 
     

</manifest>

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