Android Studio学习路程（10）

今天学习了制作登录页面，并实现记住账户的功能。

package com.example.hp.app4;

import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.EditText;

public class MainActivity extends ActionBarActivity {
    private EditText mEtPhone;
    private EditText mEtPasswd;
    private CheckBox mCBPsd;
    private String TAG ="MainActivity";
    private String SP_PHONE = "sp_phone";
    private String SP_PASSWD = "sp_passwd";
    private String SP_IS_REMEMBER_PSD = "sp_is_remember_psd";
    private SharedPreferences sharedPreferences;
    private boolean mIsChecked=false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //初始化控件
        initUI();
        //初始化数据
        initData();
    }

    private void initData() {
        //实例化sharedPreferences对象
        if(sharedPreferences==null){
            sharedPreferences = getApplicationContext().getSharedPreferences("config", Context.MODE_PRIVATE);
        }
        //回显数据
        mEtPhone.setText(sharedPreferences.getString(SP_PHONE,""));
        mEtPasswd.setText(sharedPreferences.getString(SP_PASSWD,""));
        mCBPsd.setChecked(mIsChecked);
    }

    private void initUI() {
        //获取电话和密码输入框
        mEtPhone = (EditText) findViewById(R.id.et_phone);
        //文本改变之后记录电话
        mEtPhone.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

            }

            @Override
            public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {

            }

            @Override
            public void afterTextChanged(Editable editable) {
                if(mIsChecked){
                    if(sharedPreferences==null){
                        sharedPreferences = getApplicationContext().getSharedPreferences("config", Context.MODE_PRIVATE);
                    }
                    SharedPreferences.Editor edit = sharedPreferences.edit();
                    edit.putString(SP_PHONE, mEtPhone.getText().toString());
                    edit.commit();
                }
            }
        });
        mEtPasswd = (EditText) findViewById(R.id.et_passwd);
        mEtPasswd.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

            }

            @Override
            public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {

            }

            @Override
            public void afterTextChanged(Editable editable) {
                if(mIsChecked){
                    if(sharedPreferences==null){
                        sharedPreferences = getApplicationContext().getSharedPreferences("config", Context.MODE_PRIVATE);
                    }
                    SharedPreferences.Editor edit = sharedPreferences.edit();
                    edit.putString(SP_PASSWD, mEtPasswd.getText().toString());
                    edit.commit();
                }
            }
        });
        //获取多选按钮
        mCBPsd = (CheckBox) findViewById( R.id.cb_remember_psd);
        mCBPsd.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean isChecked) {
                Log.d(TAG, "状态为：" + isChecked);
                mIsChecked = isChecked;
                if (isChecked) {
                    //实例化SharedPreferences对象
                    if (sharedPreferences == null) {
                        sharedPreferences = getApplicationContext().getSharedPreferences("config", Context.MODE_PRIVATE);
                    }
                    //实例化SharedPreferences的编辑者对象
                    SharedPreferences.Editor edit = sharedPreferences.edit();
                    edit.putString(SP_PHONE, mEtPhone.getText().toString());
                    edit.putString(SP_PASSWD, mEtPasswd.getText().toString());
                    edit.putBoolean(SP_IS_REMEMBER_PSD, isChecked);
                    //提交
                    edit.commit();


                }
            }
        });
    }
}

<?xml version="1.0" encoding="utf-8"?>
<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: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="com.example.hp.app4.MainActivity">

    <EditText
        android:id="@+id/et_phone"
        android:inputType="phone"
        android:hint="电话:"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <EditText
        android:id="@+id/et_passwd"
        android:inputType="textPassword"
        android:hint="密码:"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
    <CheckBox
        android:id="@+id/cb_remember_psd"
        android:text="记住账户"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <Button
        android:id="@+id/btn_denglu"
        android:text="登录"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
</LinearLayout>

下面是运行的结果截图：

 然后虚拟机上返回，再打开：