Android login interface is implemented through file storage

 

Layout code:

<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">

<! -- User Name layout -->

<LinearLayout

Android: layout_width = "match_parent"

Android: layout_height = "wrap_content">

<TextView

Android: id = "@ + id/view_name"

Android: layout_width = "wrap_content"

Android: layout_height = "wrap_content"

Android: text = "@ string/text_name"/>

<EditText

Android: id = "@ + id/edit_name"

Android: layout_width = "0dp"

Android: layout_height = "wrap_content"

Android: layout_weight = "1"

Android: EMS = "10"

Android: inputType = "textPersonName">

<RequestFocus/>

</EditText>

</LinearLayout>

<! -- Password layout -->

<LinearLayout

Android: layout_width = "match_parent"

Android: layout_height = "wrap_content">

<TextView

Android: id = "@ + id/view_pass"

Android: layout_width = "wrap_content"

Android: layout_height = "wrap_content"

Android: text = "@ string/text_pass"/>

<EditText

Android: id = "@ + id/edit_pass"

Android: layout_width = "0dp"

Android: layout_height = "wrap_content"

Android: layout_weight = "1"

Android: EMS = "10"

Android: inputType = "textPassword">

<RequestFocus/>

</EditText>

</LinearLayout>

<LinearLayout

Android: layout_width = "match_parent"

Android: layout_height = "wrap_content">

<Button

Android: id = "@ + id/btn_login"

Android: layout_marginLeft = "0dp"

Android: layout_width = "wrap_content"

Android: layout_height = "wrap_content"

Android: text = "@ string/text_login"/>

<CheckBox

Android: id = "@ + id/cbx_rember"

Android: layout_marginLeft = "100dp"

Android: layout_width = "wrap_content"

Android: layout_height = "wrap_content"

Android: text = "@ string/text_rember"/>

</LinearLayout>

</LinearLayout>

Code in Value: <? Xml version = "1.0" encoding = "UTF-8"?>

<Resources>

<String name = "app_name"> lession02-file </string>

<String name = "action_settings"> Settings </string>

<String name = "hello_world"> Hello world! </String>

<String name = "text_name"> User name: </string>

<String name = "text_pass"> password: </string>

<String name = "text_login"> login </string>

<String name = "text_rember"> Remember password </string>

</Resources>

:

 

Code in logActivi:

Package com. example. file;

Import java. io. IOException;

Import java. util. Map;

Import www.csdn.net. service. FileService;

Import android. app. Activity;

Import android. OS. Bundle;

Import android. text. TextUtils;

Import android. view. Menu;

Import android. view. View;

Import android. widget. Button;

Import android. widget. CheckBox;

Import android. widget. EditText;

Import android. widget. Toast;

 

Public class LoginActivity extends Activity {

// Declare the user name and password component

Public EditText edit_name, edit_pass;

// Declare the login Button Object

Public Button btn_login;

// Declare the CheckBox Component Object

Public CheckBox box_remember;

// Create a Business Object

Public FileService fileService;

@ Override

Protected void onCreate (Bundle savedInstanceState ){

Super. onCreate (savedInstanceState );

// Set the display view

SetContentView (R. layout. activity_login );

// Instantiate the Business Object

FileService = new FileService (this );

// Obtain the Component Object Based on the id.

Edit_name = (EditText) findViewById (R. id. edit_name );

Edit_pass = (EditText) findViewById (R. id. edit_pass );

Btn_login = (Button) findViewById (R. id. btn_login );

Box_remember = (CheckBox) findViewById (R. id. cbx_rember );

// Register an event for the button

Btn_login.setOnClickListener (new MyOnClickListener ());

 

// Echo data

Map <String, String> map = null;

Try {

Map = fileService. readFile ("private.txt ");

} Catch (IOException e ){

// TODO Auto-generated catch block

E. printStackTrace ();

}

If (map! = Null ){

Edit_name.setText (map. get ("name "));

Edit_pass.setText (map. get ("pass "));

}

}

@ Override

Public boolean onCreateOptionsMenu (Menu menu ){

// Inflate the menu; this adds items to the action bar if it is present.

GetMenuInflater (). inflate (R. menu. login, menu );

Return true;

}

// Internal class

Class MyOnClickListener implements View. OnClickListener {

@ Override

Public void onClick (View v ){

Int id = v. getId ();

// Determine whether the selected component is a button

If (id = btn_login.getId ()){

// Obtain the user name and password

String name = edit_name.getText (). toString ();

String pass = edit_pass.getText (). toString ();

// Determine whether the user name and password are empty

If (TextUtils. isEmpty (name) | TextUtils. isEmpty (pass )){

Toast. makeText (LoginActivity. this, "the user name or password cannot be blank ",

Toast. LENGTH_LONG). show ();

Return;

} Else {

// If you remember to check the password

If (box_remember.isChecked ()){

// Save

// Call the Business Method of the Business Object

Try {

LoginActivity. this. fileService. saveToRom (name, pass, "private.txt ");

} Catch (IOException e ){

// TODO Auto-generated catch block

E. printStackTrace ();

}

Toast. makeText (LoginActivity. this, "the user name and password need to be saved ",

Toast. LENGTH_LONG). show ();

} Else {

// Do not save

Toast. makeText (LoginActivity. this, "the user name and password do not need to be saved ",

Toast. LENGTH_LONG). show ();

}

}

}

}

}

}

Service;

Package www.csdn.net. service;

Import java. io. FileInputStream;

Import java. io. FileNotFoundException;

Import java. io. FileOutputStream;

Import java. io. IOException;

Import java. util. HashMap;

Import java. util. Map;

Import www.csdn.net. tools. StreamTools;

Import android. content. Context;

Public class FileService {

// Context object

Public Context context;

Public FileService (Context context ){

This. context = context;

}

/**

* User name and password storage operations on the phone memory

* @ Param name

* @ Param pass

* @ Param fileName

* @ Return

* @ Throws IOException

*/

Public boolean saveToRom (String name, String pass, String fileName) throws IOException {

Try {

// Obtain the output stream object of a file through the openFileOutput () method

FileOutputStream fos = context. openFileOutput (fileName, Context. MODE_PRIVATE );

// Concatenate the user name and password

String result = name + ":" + pass;

Fos. write (result. getBytes ());

Fos. flush ();

Fos. close ();

} Catch (FileNotFoundException e ){

E. printStackTrace ();

Return false;

}

Return true;

}

// Read data

Public Map <String, String> readFile (String fileName) throws IOException {

Map <String, String> map = null; // new HashMap <String, String> ();

Try {

FileInputStream FCM = context. openFileInput (fileName );

String value = StreamTools. getValue (FCM );

String values [] = value. split (":");

If (values. length> 0 ){

Map = new HashMap <String, String> ();

Map. put ("name", values [0]);

Map. put ("pass", values [1]);

}

} Catch (FileNotFoundException e ){

// TODO Auto-generated catch block

E. printStackTrace ();

}

Return map;

}

}

A tool called:

Package www.csdn.net. tools;

Import java. io. ByteArrayOutputStream;

Import java. io. FileInputStream;

Import java. io. IOException;

Public class StreamTools {

Public static String getValue (FileInputStream ISI) throws IOException {

// Byte output stream object

ByteArrayOutputStream stream = new ByteArrayOutputStream ();

Byte [] buffer = new byte [1024];

Int length = 1;

While (length = FS. read (buffer ))! =-1 ){

Stream. write (buffer, 0, length );

}

Stream. flush ();

Stream. close ();

String value = stream. toString ();

Return value;

}

}

 

 

 

In the work Window, find File Explorer and display it to the console:

Data-com.example-files-private.txt

Displayed Number of bureaus: aaa 123