Usage

1. NotificationManager类
   1. 获取NotificationManager对象,通过Content.getSystemService方法：

        1. 获取对象方法
        NotificationManager manager=(NotificationManager) 
        getSystemService(NOTIFICATION_SERVICE);

        2.源码实现
        public static NotificationManager from(Context context) {
            return (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
        }
2. 通知Notification类在通知栏显示通知，通过` NotificationManager.notify() `方

        1. 使用方法
            manager.notify(1,notification);

        2. 源码实现
        /**
         * Post a notification to be shown in the status bar. If a notification with
         * the same id has already been posted by your application and has not yet been canceled, it
         * will be replaced by the updated information.
         * @param id An identifier for this notification unique within your
         *        application.
         * @param notification A {@link Notification} object describing what to show the user. Must not
         *        be null.
         */
        public void notify(int id, Notification notification)
        {
            notify(null, id, notification);
        }

2. Notification类
   1. 构造 Notification,通过Notification.Builder或者NotificationCompat.Builder方法

 1. 关于 `Notification` 的构造函数,新版本的 ** android API ** 已经不推荐使用构造函数来生成 `Notification` 对象了:

            /*** Constructs a Notification object with default values.
             * You might want to consider using {@link Builder} instead.
             */
            public Notification()
            {
                this.when = System.currentTimeMillis();
                this.priority = PRIORITY_DEFAULT;
            }
            /**
             * @hide
             */
            public Notification(Context context, int icon, CharSequence tickerText, long when,
                    CharSequence contentTitle, CharSequence contentText, Intent contentIntent)
            {
                new Builder(context)
                        .setWhen(when)
                        .setSmallIcon(icon)
                        .setTicker(tickerText)
                        .setContentTitle(contentTitle)
                        .setContentText(contentText)
                        .setContentIntent(PendingIntent.getActivity(context, 0, contentIntent, 0))
                        .buildInto(this);
            }
            @Deprecated
            public Notification(int icon, CharSequence tickerText, long when)
            {
                this.icon = icon;
                this.tickerText = tickerText;
                this.when = when;
            }
> 
 2. `Notification.setLatestEventInfo`()也被新版本的API给废弃了
            * @deprecated Use {@link Builder} instead.
           * @removed
           */
            @Deprecated
            public void setLatestEventInfo(Context context,
                    CharSequence contentTitle, CharSequence contentText, PendingIntent contentIntent) {
            Notification.Builder builder = new Notification.Builder(context);
            // First, ensure that key pieces of information that may have been set directly
            // are preserved
            builder.setWhen(this.when);
            builder.setSmallIcon(this.icon);
            builder.setPriority(this.priority);
            builder.setTicker(this.tickerText);
            builder.setNumber(this.number);
            builder.setColor(this.color);
            builder.mFlags = this.flags;
            builder.setSound(this.sound, this.audioStreamType);
            builder.setDefaults(this.defaults);
            builder.setVibrate(this.vibrate);
            builder.setDeleteIntent(this.deleteIntent);
            // now apply the latestEventInfo fields
            if (contentTitle != null) {
                builder.setContentTitle(contentTitle);
            }
            if (contentText != null) {
                builder.setContentText(contentText);
            }
            builder.setContentIntent(contentIntent);
            builder.buildInto(this);
            }      
 3. 新版本的API生成 `Notification` 对象 
     - 先生成` Builder `对象B
            Notification.Builder builder = new Notification.Builder(this);
            或者
            NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this);
     - 设置 `Builder` 对象的参数
            builder.setContentIntent(pendingIntent);
            builder.setSmallIcon(R.drawable.lanucher);
            builder.setLargeIcon(BitmapFactory.decodeResource(getResources(),     R.drawable.lanucher));
            builder.setAutoCancel(true);
            builder.setContentTitle("普通通知");
     - 再通过`Builder`的成员函数`Builder.build()`来生成 `Notification` 对象
            Notification notification= builder.build();
     - 通常生成 `Notification` 对象,如下：
            Notification notification = new Notification.Builder(context)    
                     .setAutoCancel(true)    
                     .setContentTitle("title")    
                     .setContentText("describe")    
                     .setContentIntent(pendingIntent)    
                     .setSmallIcon(R.drawable.ic_launcher)    
                     .setWhen(System.currentTimeMillis())    
                     .build();

代码实现：

1. **MainActivity.java**

    package com.fd.notification;
    import android.app.Notification;
    import android.app.NotificationManager;
    import android.app.PendingIntent;
    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 AppCompatActivity {        
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);        
            Button send_noti=(Button) findViewById(R.id.send_noti);
            send_noti.setOnClickListener(send_notiListener);
        }
        //实现点击按钮发送通知操作
        private Button.OnClickListener send_notiListener=new Button.OnClickListener(){
            public void onClick(View v){
                send_NotiToReceiver();
            }
        };
        //发送通知
        private void send_NotiToReceiver(){
            NotificationManager notiManager=(NotificationManager) getSystemService(NOTIFICATION_SERVICE);
            Notification notiMessage=buildNoti("Click goto NotiActivity","Noti");
            loadNotiConfig(notiMessage);
            notiManager.notify(0,notiMessage);
        }
        //生成通知内容
        private Notification buildNoti(String NotiText,String NotiTitle){
            Notification.Builder builder=new Notification.Builder(this);
            PendingIntent pIntent=buildPendingIntent();
            builder.setContentIntent(pIntent);
            builder.setContentText(NotiText);
            builder.setContentTitle(NotiTitle);
            builder.setSmallIcon(R.mipmap.noti_iocn);
            builder.setAutoCancel(true);
            builder.setWhen(System.currentTimeMillis());
            return builder.build();
        }
        //加载声音、震动、提示灯等
        private void loadNotiConfig(Notification notification){
            notification.defaults |=Notification.DEFAULT_LIGHTS;
            notification.defaults |=Notification.DEFAULT_SOUND;
            notification.defaults |=Notification.DEFAULT_VIBRATE;
        }
        //生成PendingIntent对象
        private PendingIntent buildPendingIntent(){
            Intent intent=new Intent(this,NotiActivity.class);
            PendingIntent pIntent=PendingIntent.getActivity(this,0,intent,0);
            return pIntent;
        }
    }