Android开发之完成登陆界面的数据保存回显操作实例

本文实例讲述了Android开发之完成登陆界面的数据保存回显操作。分享给大家供大家参考，具体如下：

LoginActivity.java：

package com.example.login;
import java.util.Map;
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;
import com.example.login.service.FileService;
public class LoginActivity extends Activity {
  public EditText edit_name,edit_pass;
  public Button btn_login;
  public CheckBox box_remeber;
  public FileService fileService;
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_login);
    fileService=new FileService(this);
    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_remeber=(CheckBox) findViewById(R.id.cbx_remember);
    btn_login.setOnClickListener(new MyOnClickListener());
    Map<String, String> map=fileService.readFile("private.txt");
    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;
  }
  class MyOnClickListener implements View.OnClickListener{
    @Override
    public void onClick(View v) {
      int id=v.getId();
      switch (id) {
      case R.id.btn_login:
        String name=edit_name.getText().toString();
        String pass=edit_pass.getText().toString();
        if(TextUtils.isEmpty(name)){
          Toast.makeText(LoginActivity.this, "用户名不能为空", Toast.LENGTH_SHORT).show();
          return;
        }else if(TextUtils.isEmpty(pass)){
          Toast.makeText(LoginActivity.this, "密码不能为空", Toast.LENGTH_SHORT).show();
          return;
        }else{
          if(box_remeber.isChecked()){
            LoginActivity.this.fileService.saveToRom(name, pass, "private.txt");
            Toast.makeText(LoginActivity.this, "用户名和密码已保存", Toast.LENGTH_SHORT).show();
          }else{
            Toast.makeText(LoginActivity.this, "用户名和密码不需要保存", Toast.LENGTH_SHORT).show();
          }
        }
        break;
      default:
        break;
      }
      /*if(id==btn_login.getId()){
        String name=edit_name.getText().toString();
        String pass=edit_pass.getText().toString();
        if(TextUtils.isEmpty(name)){
          Toast.makeText(LoginActivity.this, "用户名不能为空", Toast.LENGTH_SHORT).show();
          return;
        }else if(TextUtils.isEmpty(pass)){
          Toast.makeText(LoginActivity.this, "密码不能为空", Toast.LENGTH_SHORT).show();
          return;
        }else{
          if(box_remeber.isChecked()){
            LoginActivity.this.fileService.saveToRom(name, pass, "private.txt");
            Toast.makeText(LoginActivity.this, "用户名和密码已保存", Toast.LENGTH_SHORT).show();
          }else{
            Toast.makeText(LoginActivity.this, "用户名和密码不需要保存", Toast.LENGTH_SHORT).show();
          }
        }
      }*/
    }
  }
}

FileService.java：

package com.example.login.service;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.HashMap;
import java.util.Map;
import com.example.login.utils.StreamTools;
import android.content.Context;
public class FileService {
  public Context context;
  public FileService(Context context) {
    this.context = context;
  }
  public boolean saveToRom(String name,String pass,String fileName){
    try{
      FileOutputStream fos=context.openFileOutput(fileName, Context.MODE_PRIVATE);
      String result=name+":"+pass;
      fos.write(result.getBytes());
      fos.flush();
      fos.close();
    }catch(Exception e){
      e.printStackTrace();
      return false;
    }
    return true;
  }
  public Map<String,String> readFile(String fileName){
    Map<String,String> map=null;
    try{
      FileInputStream fis=context.openFileInput(fileName);
      String value=StreamTools.getValue(fis);
      String values[]=value.split(":");
      if(values.length>0){
        map=new HashMap<String, String>();
        map.put("name", values[0]);
        map.put("pass", values[1]);
      }
    }catch(Exception e){
      e.printStackTrace();
    }
    return map;
  }
}

StreamTools.java：

package com.example.login.utils;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
public class StreamTools {
  public static String getValue(FileInputStream fis) throws Exception{
    ByteArrayOutputStream stream=new ByteArrayOutputStream();
    byte[] buffer=new byte[1024];
    int length=-1;
    while((length=fis.read(buffer))!=-1){
      stream.write(buffer,0,length);
    }
    stream.flush();
    stream.close();
    String value=stream.toString();
    return value;
  }
}

login_activity.xml：

<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
  android:paddingLeft="@dimen/activity_horizontal_margin"
  android:paddingRight="@dimen/activity_horizontal_margin"
  android:paddingTop="@dimen/activity_vertical_margin"
  tools:context=".LoginActivity" >
  <LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:orientation="vertical" >
    <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>
    <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" />
    </LinearLayout>
    <LinearLayout
      android:layout_width="match_parent"
      android:layout_height="wrap_content" >
      <Button
        android:id="@+id/btn_login"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="0.17"
        android:text="@string/text_login" />
      <CheckBox
        android:id="@+id/cbx_remember"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="80dp"
        android:text="@string/text_rember" />
    </LinearLayout>
  </LinearLayout>
</RelativeLayout>

String.xml：

<?xmlversion="1.0"encoding="utf-8"?>
<resources>
<stringname="app_name">login</string>
<stringname="action_settings">Settings</string>
<stringname="hello_world">Login</string>
<stringname="text_name">用户名:</string>
<stringname="text_pass">密　码:</string>
<stringname="text_login">登陆</string>
<stringname="text_rember">记住密码</string>
</resources>

希望本文所述对大家Android程序设计有所帮助。