登录界面记住密码设计

             Loginactivity

package com.example.minitwittersimulate;

import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.Toast;


public class LoginActivity extends Activity {
	
	private SharedPreferences pref;
	private SharedPreferences.Editor editor;
	private CheckBox rememberPass;
	private EditText accountEdit;
	private EditText passwordEdit;
	private Button login;
	private TextWatcher watcher;
	private TextWatcher textWatcher;
	
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		requestWindowFeature(Window.FEATURE_NO_TITLE);
		setContentView(R.layout.activity_login);
		pref = PreferenceManager.getDefaultSharedPreferences(this);
		accountEdit = (EditText) findViewById(R.id.etUsername);
		
		passwordEdit = (EditText)findViewById( R.id.etPassword);
		rememberPass = (CheckBox)findViewById(R.id.cbRememberPass);
		login = (Button)findViewById(R.id.btnLogin);
		accountEdit.addTextChangedListener(new TextWatcher() {
			
			@Override
			public void onTextChanged(CharSequence s, int start, int before, int count) {
				// TODO Auto-generated method stub
				String edaccount = s.toString();
			    String isaccount = pref.getString("account","");
			    if(isaccount.equal(edaccount)){
			    	String password = pref.getString("password", "" );
					passwordEdit.setText(password);
					rememberPass.setChecked(true);
			    }
			}
			
			@Override
			public void beforeTextChanged(CharSequence s, int start, int count,
					int after) {
				// TODO Auto-generated method stub
				
			}
			
			@Override
			public void afterTextChanged(Editable s) {
				// TODO Auto-generated method stub
			
			}
		});
		login.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				String account = accountEdit.getText().toString();
				String password = passwordEdit.getText().toString();
				if(account.equals("admin")&&password.equals("123456")){
					editor = pref.edit();
					if(rememberPass.isChecked()){
						editor.putBoolean("remember_password", true);
						editor.putString("account", account);
						editor.putString("password", password);
						
					}else{
						editor.clear();
					}
					editor.commit();
					Intent intent = new Intent(LoginActivity.this,MainActivity.class);
					startActivity(intent);
					finish();
				}else{
					Toast.makeText(LoginActivity.this, "account or password is invalid", Toast.LENGTH_LONG).show();
				}
				
			}
		});
		
	}

}

布局文件：：

<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:background="@drawable/loginbg"
    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" >

  <include layout="@layout/login_top"/> 
  <include layout="@layout/login_bottom"/>"

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

    <TextView
        android:id="@+id/tvRegist"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_marginLeft="21dp"
        android:layout_marginTop="18dp"
        android:text="@string/tvRegister"
        android:autoLink="all"
        android:textColorLink="#FF0066CC" />

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_marginBottom="24dp"
        android:src="@drawable/panda" />

    <ImageView
        android:id="@+id/imageView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="28dp"
        android:src="@drawable/icon" />

</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/btnbg_roundcorner"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin" >

    <TextView
        android:id="@+id/tvUsername"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:text="@string/tvName"
        android:textAppearance="?android:attr/textAppearanceMedium" />

    <EditText
        android:id="@+id/etUsername"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/tvUsername"
        android:layout_below="@+id/tvUsername"
        android:background="@android:drawable/edit_text"
        android:ems="10" >

        <requestFocus />
    </EditText>

    <TextView
        android:id="@+id/tvPassword"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/etUsername"
        android:layout_below="@+id/etUsername"
        android:text="@string/tvPassword"
        android:textAppearance="?android:attr/textAppearanceMedium" />

    <EditText
        android:id="@+id/etPassword"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/tvPassword"
        android:layout_below="@+id/tvPassword"
        android:background="@android:drawable/edit_text"
        android:ems="10"
        android:inputType="textPassword" />

    <CheckBox
        android:id="@+id/cbRememberPass"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/btnLogin"
        android:layout_alignBottom="@+id/btnLogin"
        android:layout_alignLeft="@+id/etPassword"
        android:text="记住密码"
        android:textSize="20sp" />

    <Button
        android:id="@+id/btnLogin"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignRight="@+id/etPassword"
        android:layout_below="@+id/etPassword"
        android:background="#FF72CAE1"
        android:onClick="login"
        android:text="@string/btnLogin" />

</RelativeLayout>