Android8.0通知

android里面经常会使用Notification来显示通知的消息，一般使用NotificationManager来创建通知消息

 NotificationManager manger = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
        //为了版本兼容  选择V7包下的NotificationCompat进行构造
        NotificationCompat.Builder builder = new NotificationCompat.Builder(context);
        //Ticker是状态栏显示的提示
        builder.setTicker("1");
        //第一行内容  通常作为通知栏标题
        builder.setContentTitle("推送标题");
        //第二行内容 通常是通知正文
        builder.setContentText("内容");
        //可以点击通知栏的删除按钮删除
        builder.setAutoCancel(true);
        //系统状态栏显示的小图标
        builder.setSmallIcon(R.mipmap.ic_launcher);
        Notification notification = builder.build();
        notification.sound = Uri.parse("android.resource://"
                + context.getPackageName() + "/" + R.raw.ti);
        builder.setDefaults(NotificationCompat.DEFAULT_VIBRATE | NotificationCompat.DEFAULT_LIGHTS);
        notification.flags |= Notification.FLAG_AUTO_CANCEL;
//        Intent clickIntent = new Intent(); //点击通知之后要发送的广播
//        int id = (int) (System.currentTimeMillis() / 1000);
//        clickIntent.addCategory(context.getPackageName());
//        clickIntent.setAction(JPushInterface.ACTION_NOTIFICATION_OPENED);
//        clickIntent.putExtra(JPushInterface.EXTRA_EXTRA, bundle.getString(JPushInterface.EXTRA_EXTRA));
//        PendingIntent contentIntent = PendingIntent.getBroadcast(context, id, clickIntent, PendingIntent.FLAG_UPDATE_CURRENT);
//        notification.contentIntent = contentIntent;
        manger.notify(1, notification);

　　然而在Android8.0以上的版本并不能看到通知的内容，android8.0需要使用NotificationChannel来处理通知的显示，根据处理得到了以下内容。

package com.snail.monitor.util;

import android.annotation.TargetApi;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.ContextWrapper;
import android.content.Intent;
import android.graphics.BitmapFactory;
import android.graphics.Color;
import android.os.Build;
import android.support.v4.app.NotificationCompat;

import com.snail.monitor.R;

import cn.jpush.android.api.JPushInterface;

import static android.app.Notification.VISIBILITY_SECRET;
import static android.support.v4.app.NotificationCompat.PRIORITY_DEFAULT;

/**
 * Created by zd on 2019/1/7.
 */

public class NotificationUtils extends ContextWrapper {

    public static final String CHANNEL_ID = "default";
    private static final String CHANNEL_NAME = "Default Channel";
    private static final String CHANNEL_DESCRIPTION = "this is default channel!";
    private NotificationManager mManager;

    private Context context;
    private String EXTRA_EXTRA;
    public NotificationUtils(Context base,String EXTRA_EXTRA) {
        super(base);
        context = base;
        this.EXTRA_EXTRA = EXTRA_EXTRA;
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            createNotificationChannel();
        }
    }

    @TargetApi(Build.VERSION_CODES.O)
    private void createNotificationChannel() {
        NotificationChannel channel = new NotificationChannel(CHANNEL_ID, CHANNEL_NAME, NotificationManager.IMPORTANCE_DEFAULT);
        //是否绕过请勿打扰模式
        channel.canBypassDnd();
        //闪光灯
        channel.enableLights(true);
        //锁屏显示通知
        channel.setLockscreenVisibility(VISIBILITY_SECRET);
        //闪关灯的灯光颜色
        channel.setLightColor(Color.RED);
        //桌面launcher的消息角标
        channel.canShowBadge();
        //是否允许震动
        channel.enableVibration(true);
        //获取系统通知响铃声音的配置
        channel.getAudioAttributes();
        //获取通知取到组
        channel.getGroup();
        //设置可绕过  请勿打扰模式
        channel.setBypassDnd(true);
        //设置震动模式
        channel.setVibrationPattern(new long[]{100, 100, 200});
        //是否会有灯光
        channel.shouldShowLights();
        getManager().createNotificationChannel(channel);
    }

    private NotificationManager getManager() {
        if (mManager == null) {
            mManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        }
        return mManager;
    }

    /**
     * 发送通知
     */
    public void sendNotification(String title, String content) {
        NotificationCompat.Builder builder = getNotification(title, content);
        getManager().notify(1, builder.build());
    }

    private NotificationCompat.Builder getNotification(String title, String content) {
        NotificationCompat.Builder builder = null;
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            builder = new NotificationCompat.Builder(getApplicationContext(), CHANNEL_ID);
        } else {
            builder = new NotificationCompat.Builder(getApplicationContext());
            builder.setPriority(PRIORITY_DEFAULT);
        }
        //标题
        builder.setContentTitle(title);
        //文本内容
        builder.setContentText(content);
        //小图标
        builder.setSmallIcon(R.mipmap.ic_launcher);
        //设置点击信息后自动清除通知
        builder.setAutoCancel(true);
        Intent clickIntent = new Intent(); //点击通知之后要发送的广播
        int id = (int) (System.currentTimeMillis() / 1000);
        clickIntent.addCategory(context.getPackageName());
        clickIntent.setAction(JPushInterface.ACTION_NOTIFICATION_OPENED);
        clickIntent.putExtra(JPushInterface.EXTRA_EXTRA, EXTRA_EXTRA);
        PendingIntent contentIntent = PendingIntent.getBroadcast(context, id, clickIntent, PendingIntent.FLAG_UPDATE_CURRENT);

        builder.setContentIntent(contentIntent);

        return builder;
    }

    /**
     * 发送通知
     */
    public void sendNotification(int notifyId, String title, String content) {
        NotificationCompat.Builder builder = getNotification(title, content);
        getManager().notify(notifyId, builder.build());
    }

}