ذخیره و بازیابی تنظیمات کاربر

<?xml version=”1.0” encoding=”utf-8”?>
<LinearLayout xmlns:android=”http://schemas.android.com/apk/res/android”
android:orientation=”vertical”
android:layout_width=”fill_parent”
android:layout_height=”fill_parent” >
<SeekBar
android:id=”@+id/SeekBar01”
android:layout_width=”fill_parent”
android:layout_height=”wrap_content” />
<TextView
android:id=”@+id/TextView01”
android:layout_width=”fill_parent”
android:layout_height=”wrap_content”
android:text=”@string/hello” />
<EditText
android:id=”@+id/EditText01”
android:layout_width=”fill_parent”
android:layout_height=”wrap_content” />
<Button
android:id=”@+id/btnSave”
android:text=”Save”
android:layout_width=”wrap_content”
android:layout_height=”wrap_content” />
</LinearLayout>

package com.PRG.SharedPreferences;
import android.app.Activity;
import android.os.Bundle;
import android.content.SharedPreferences;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.Toast;
public class MainActivity extends Activity {
private SharedPreferences prefs;
private String prefName = “MyPref”;
private EditText editText;
private SeekBar seekBar;
private Button btn;
private static final String FONT_SIZE_KEY = “fontsize”;
private static final String TEXT_VALUE_KEY = “textvalue”;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
editText = (EditText) findViewById(R.id.EditText01);
seekBar = (SeekBar) findViewById(R.id.SeekBar01);
btn = (Button) findViewById(R.id.btnSave);
btn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
//---get the SharedPreferences object---
prefs = getSharedPreferences(prefName, MODE_PRIVATE);
SharedPreferences.Editor editor = prefs.edit();
//---save the values in the EditText view to preferences---
editor.putFloat(FONT_SIZE_KEY, editText.getTextSize());
editor.putString(TEXT_VALUE_KEY, editText.getText().toString());
//---saves the values---
editor.commit();
//---display file saved message---
Toast.makeText(getBaseContext(),
“Font size saved successfully!”,
Toast.LENGTH_SHORT).show();
}
});
//---load the SharedPreferences object---
SharedPreferences prefs = getSharedPreferences(prefName, MODE_PRIVATE);
//---set the TextView font size to the previously saved values---
float fontSize = prefs.getFloat(FONT_SIZE_KEY, 12);
//---init the SeekBar and EditText---
seekBar.setProgress((int) fontSize);
editText.setText(prefs.getString(TEXT_VALUE_KEY, “”));
editText.setTextSize(seekBar.getProgress());
seekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
//---change the font size of the EditText---
editText.setTextSize(progress);
}
});
}
}

private SharedPreferences prefs;
...
//---get the SharedPreferences object---
prefs = getSharedPreferences(prefName, MODE_PRIVATE);
SharedPreferences.Editor editor = prefs.edit();

//---save the values in the EditText view to preferences---
editor.putFloat(FONT_SIZE_KEY, editText.getTextSize());
editor.putString(TEXT_VALUE_KEY, editText.getText().toString());
//---saves the values---
editor.commit();

//---load the SharedPreferences object---
SharedPreferences prefs = getSharedPreferences(prefName, MODE_PRIVATE);
//---set the TextView font size to the previously saved values---
float fontSize = prefs.getFloat(FONT_SIZE_KEY, 12);
//---init the SeekBar and EditText---
seekBar.setProgress((int) fontSize);
editText.setText(prefs.getString(TEXT_VALUE_KEY, “”));
editText.setTextSize(seekBar.getProgress());

/data/data/<package_name>/shared_prefs فولدر

<?xml version=’1.0’ encoding=’utf-8’ standalone=’yes’ ?>
<map>
<string name=”textvalue”>This is so cool!</string>
<float name=”fontsize” value=”75.0” />
</map>

<?xml version=”1.0” encoding=”utf-8”?>
<LinearLayout xmlns:android=”http://schemas.android.com/apk/res/android”
android:orientation=”vertical”
android:layout_width=”fill_parent”
android:layout_height=”fill_parent” >
<TextView
android:layout_width=”fill_parent”
android:layout_height=”wrap_content”
android:text=”Please enter some text”
/>
<EditText
android:id=”@+id/txtText1”
android:layout_width=”fill_parent”
android:layout_height=”wrap_content” />
<Button
android:id=”@+id/btnSave”
android:text=”Save”
android:layout_width=”fill_parent”
android:layout_height=”wrap_content” />
<Button
android:id=”@+id/btnLoad”
android:text=”Load”
android:layout_width=”fill_parent”
android:layout_height=”wrap_content” />
</LinearLayout>

package com.PRG.Files;
import android.app.Activity;
import android.view.View;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import android.os.Bundle;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends Activity {
private EditText textBox;
private static final int READ_BLOCK_SIZE = 100;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
textBox = (EditText) findViewById(R.id.txtText1);
Button saveBtn = (Button) findViewById(R.id.btnSave);
Button loadBtn = (Button) findViewById(R.id.btnLoad);
saveBtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
String str = textBox.getText().toString();
try
{
FileOutputStream fOut =
openFileOutput(“textfile.txt”,
MODE_WORLD_READABLE);
OutputStreamWriter osw = new
OutputStreamWriter(fOut);
//---write the string to the file---
osw.write(str);
osw.flush();
osw.close();
//---display file saved message---
Toast.makeText(getBaseContext(),
“File saved successfully!”,
Toast.LENGTH_SHORT).show();
//---clears the EditText---
textBox.setText(“”);
}
catch (IOException ioe)
{
ioe.printStackTrace();
}
}
});

FileOutputStream fOut =
openFileOutput(“textfile.txt”,
MODE_WORLD_READABLE);

OutputStreamWriter osw = new
OutputStreamWriter(fOut);

osw.write(str);
osw.flush();
osw.close();

FileInputStream fIn =
openFileInput(“textfile.txt”);
InputStreamReader isr = new
InputStreamReader(fIn);

char[] inputBuffer = new char[READ_BLOCK_SIZE];
String s = “”;
int charRead;
while ((charRead = isr.read(inputBuffer))>0)
{
//---convert the chars to a String---
String readString =
String.copyValueOf(inputBuffer, 0,
charRead);
s += readString;
inputBuffer = new char[READ_BLOCK_SIZE];
}

saveBtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
String str = textBox.getText().toString();
try
{
//---SD Card Storage---
File sdCard = Environment.getExternalStorageDirectory();
File directory = new File (sdCard.getAbsolutePath() +
“/MyFiles”);
directory.mkdirs();
File file = new File(directory, “textfile.txt”);
FileOutputStream fOut = new FileOutputStream(file);
OutputStreamWriter osw = new
OutputStreamWriter(fOut);
//---write the string to the file---
osw.write(str);
osw.flush();
osw.close();
//---display file saved message---
Toast.makeText(getBaseContext(),
“File saved successfully!”,
Toast.LENGTH_SHORT).show();
//---clears the EditText---
textBox.setText(“”);
}
catch (IOException ioe)
{
ioe.printStackTrace();
}
}
});

loadBtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try
{
//---SD Storage---
File sdCard = Environment.getExternalStorageDirectory();
File directory = new File (sdCard.getAbsolutePath() +
“/MyFiles”);
File file = new File(directory, “textfile.txt”);
FileInputStream fIn = new FileInputStream(file);
InputStreamReader isr = new InputStreamReader(fIn);
char[] inputBuffer = new char[READ_BLOCK_SIZE];
String s = “”;
int charRead;
while ((charRead = isr.read(inputBuffer))>0)
{
//---convert the chars to a String---
String readString =
String.copyValueOf(inputBuffer, 0, charRead);
s += readString;
inputBuffer = new char[READ_BLOCK_SIZE];
}
//---set the EditText to the text that has been
// read---
textBox.setText(s);
Toast.makeText(getBaseContext(),
“File loaded successfully!”,
Toast.LENGTH_SHORT).show();
}
catch (IOException ioe) {
ioe.printStackTrace();
}
}
});

<?xml version=”1.0” encoding=”utf-8”?>
<manifest xmlns:android=”http://schemas.android.com/apk/res/android”
package=”net.learn2develop.Files”
android:versionCode=”1”
android:versionName=”1.0”>
<application android:icon=”@drawable/icon” android:label=”@string/app_name”>
<activity android:name=”.MainActivity”
android:label=”@string/app_name”>
<intent-filter>
<action android:name=”android.intent.action.MAIN” />
<category android:name=”android.intent.category.LAUNCHER” />
</intent-filter>
</activity>
</application>
<uses-sdk android:minSdkVersion=”9” />
<uses-permission android:name=”android.permission.WRITE_EXTERNAL_STORAGE”>
</uses-permission>
</manifest>