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MKT-porter
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第一行代码 6.1-6.4 数据存储全方案-详解持久化数据-SharedPreferences

 

 

 

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">


<EditText
android:id="@+id/account"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:layout_gravity="center_vertical"/>

  

 

 

 

 

 

 

 

 

 

 

两个界面布局

布局一 登录界面

 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    
    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="60dp">
        <TextView
            android:layout_width="90dp"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:textSize="18sp"
            android:text="Account:" />

        <EditText
            android:id="@+id/account"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:layout_gravity="center_vertical"/>
    </LinearLayout>

    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="60dp">
        <TextView
            android:layout_width="90dp"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:textSize="18sp"
            android:text="Password:" />

        <EditText
            android:id="@+id/password"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:layout_gravity="center_vertical"
            android:inputType="textPassword" />
    </LinearLayout>

    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <CheckBox
            android:id="@+id/remember_pass"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="18sp"
            android:text="Remember password" />

    </LinearLayout>

    <Button
        android:id="@+id/login"
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:text="Login" />

</LinearLayout>

  

 

布局二

  

主界面

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

    <Button
        android:id="@+id/force_offline"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Send force offline broadcast" />

</LinearLayout>

 

登录界面主活动

 

 

 

package com.example.broadcastbestpractice;

import android.content.Intent;
import android.content.SharedPreferences;
import android.preference.PreferenceManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.Toast;

public class LoginActivity extends BaseActivity {

    private SharedPreferences pref;

    private SharedPreferences.Editor editor;

    private EditText accountEdit;

    private EditText passwordEdit;

    private Button login;

    private CheckBox rememberPass;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);// 打开登陆布局
        
        // 读取信息
        pref = PreferenceManager.getDefaultSharedPreferences(this);
        
        //  按键 编辑框ID
        accountEdit = (EditText) findViewById(R.id.account);
        passwordEdit = (EditText) findViewById(R.id.password);
        rememberPass = (CheckBox) findViewById(R.id.remember_pass);
        login = (Button) findViewById(R.id.login);
        
        // 设置 可选按钮 否
        boolean isRemember = pref.getBoolean("remember_password", false);
        if (isRemember) {
            // 将账号和密码 读取到文本框中
            String account = pref.getString("account", "");
            String password = pref.getString("password", "");
            accountEdit.setText(account);
            passwordEdit.setText(password);
            rememberPass.setChecked(true);
        }
        
        // 登陆  按键函数
        
        login.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String account = accountEdit.getText().toString();
                String password = passwordEdit.getText().toString();
                // 如果账号是admin且密码是123456,就认为登录成功
                if (account.equals("admin") && password.equals("123456")) {
                    editor = pref.edit();
                    if (rememberPass.isChecked()) { // 检查复选框是否被选中
                        editor.putBoolean("remember_password", true);
                        editor.putString("account", account);
                        editor.putString("password", password);
                    } else {
                        editor.clear();
                    }
                    editor.apply();//  执行储存
                    
                    Intent intent = new Intent(LoginActivity.this, MainActivity.class); //打开下个主界面
                    startActivity(intent);//开始
                    finish();//销毁当前
                } else {
                    Toast.makeText(LoginActivity.this, "account or password is invalid",
                            Toast.LENGTH_SHORT).show();
                }
            }
        });
    }

}

  

主界面活动

package com.example.broadcastbestpractice;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends BaseActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button forceOffline = (Button) findViewById(R.id.force_offline);
        forceOffline.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent("com.example.broadcastbestpractice.FORCE_OFFLINE");
                sendBroadcast(intent);
            }
        });
    }

}

  

需要注册两个界面的关系   

1 登录界面是主界面,自动启动

2 主界面是登陆界面,直接传递打开

 

 

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.broadcastbestpractice">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
        </activity>
        <activity android:name=".LoginActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

  

 

登录界面和主界面都继承了,重写了生成和销毁记录

BaseActivity类,里面添加了功能,能够很快管理所有的活动。例如销毁和生成

BaseActivity

package com.example.broadcastbestpractice;

import android.app.AlertDialog;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

public class BaseActivity extends AppCompatActivity {

    private ForceOfflineReceiver receiver;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ActivityCollector.addActivity(this);
    }

    @Override
    protected void onResume() {
        super.onResume();
        IntentFilter intentFilter = new IntentFilter();
        intentFilter.addAction("com.example.broadcastbestpractice.FORCE_OFFLINE");
        receiver = new ForceOfflineReceiver();
        registerReceiver(receiver, intentFilter);
    }

    @Override
    protected void onPause() {
        super.onPause();
        if (receiver != null) {
            unregisterReceiver(receiver);
            receiver = null;
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        ActivityCollector.removeActivity(this);
    }

    class ForceOfflineReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(final Context context, Intent intent) {
            AlertDialog.Builder builder = new AlertDialog.Builder(context);
            builder.setTitle("Warning");
            builder.setMessage("You are forced to be offline. Please try to login again.");
            builder.setCancelable(false);
            builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    ActivityCollector.finishAll(); // 销毁所有活动
                    Intent intent = new Intent(context, LoginActivity.class);
                    context.startActivity(intent); // 重新启动LoginActivity
                }
            });
            builder.show();
        }

    }

}

  

ActivityCollector


package com.example.broadcastbestpractice;

import android.app.Activity;

import java.util.ArrayList;
import java.util.List;

public class ActivityCollector {

    public static List<Activity> activities = new ArrayList<>();

    public static void addActivity(Activity activity) {
        activities.add(activity);
    }

    public static void removeActivity(Activity activity) {
        activities.remove(activity);
    }

    public static void finishAll() {
        for (Activity activity : activities) {
            if (!activity.isFinishing()) {
                activity.finish();
            }
        }
    }

}

  

 

posted on 2018-06-24 21:31  MKT-porter  阅读(238)  评论(0)    收藏  举报
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