其实在前面我写的《Notification相关操作》文章里面提了一嘴这个事情,Android 8.0以后启动Service需要采用context.startForegroundService(intent)的形式启动,而这个操作会导致一个Service必须启动一个Notification的问题,如果被要求隐藏这个Notification的话就需要采取一些特殊手段了:
判定Service是否正在后台运行的工具类:
import android.app.ActivityManager;
import android.content.Context;
public class ServiceUtil {
/**
* @param context
* @return
*/
public static boolean isServiceRunning(String strServiceName, Context context) {
ActivityManager manager = (ActivityManager) context.getSystemService(context.ACTIVITY_SERVICE);
for (ActivityManager.RunningServiceInfo service : manager.getRunningServices(Integer.MAX_VALUE)) {
if (strServiceName.equals(service.service.getClassName())) {
return true;
}
}
return false;
}
}
Service本身还是在8.0以上启动一个Notification,不过启动之后马上删除通道,这样就能隐藏Notification了
import android.app.Service;
import android.app.NotificationChannel;
import android.content.Intent;
import android.os.Handler;
import android.os.IBinder;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.graphics.BitmapFactory;
import android.os.Build;
import android.os.Looper;
import android.support.v4.app.NotificationCompat;
public class BuySellService extends Service {
private final IBinder binder = new BuySellBinder();
private NotificationManager manager = null; // 通知管理器
private String notificationChannelId = "channel_1"; // Android8.0以后展示通知需要注册的通道编号
private String notificationChannelName = "channel_name_1"; // Android8.0以后展示通知需要注册的通道名称
private Context context; // 上下文对象
private static final int notification_id = 198564; // 状态栏 notification 对象的编号
private Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
}
};
@Override
public void onCreate() {
super.onCreate();
context = BuySellService.this;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
showNotification();
}
}
@Override
public IBinder onBind(Intent intent) {
return binder;
}
public class BuySellBinder extends Binder {
public BuySellService getService() {
return BuySellService.this;
}
}
// 展示Notification的方法
private void showNotification() {
if (Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
// 创建渠道
createNotificationChannel();
// 展示通知
showHighNotification();
}/** else {
// 展示通知
showSimpleNotification();
}**/
}
// Android8.0以前的版本使用此方法启动Notification
private void showSimpleNotification() {
Notification notification = new NotificationCompat.Builder(context, notificationChannelId)
.setContentTitle("买卖客户端")
.setContentText("正在运行中...")
/**点击事件监听器**/
.setContentIntent(PendingIntent.getBroadcast(context, 0, new Intent(ConstantValues.FOREGROUND_NOTIFICATION_CLICKED), 0))
/**消失的监听器**/
.setDeleteIntent(PendingIntent.getBroadcast(context, 0, new Intent(ConstantValues.FOREGROUND_NOTIFICATION_DISMISS), 0))
.setLargeIcon(BitmapFactory.decodeResource(context.getResources(), R.mipmap.ic_launcher))
.setSmallIcon(R.mipmap.ic_launcher) //设置小图标,4.x在右边,5.x在左边
/**通知产生的时间,会在通知信息里显示**/
.setWhen(System.currentTimeMillis())
/**设置该通知优先级**/
.setPriority(Build.VERSION.SDK_INT < android.os.Build.VERSION_CODES.JELLY_BEAN ? NotificationCompat.PRIORITY_MAX : Notification.PRIORITY_MAX)
/**设置这个标志当用户单击面板就可以让通知将自动取消**/
.setAutoCancel(false)
/**设置他为一个正在进行的通知。他们通常是用来表示一个后台任务,用户积极参与(如播放音乐)或以某种方式正在等待,因此占用设备(如一个文件下载,同步操作,主动网络连接)**/
.setOngoing(true)
/**向通知添加声音、闪灯和振动效果的最简单、最一致的方式是使用当前的用户默认设置,使用defaults属性,可以组合:**/
/**.setDefaults(Notification.DEFAULT_VIBRATE or Notification.DEFAULT_SOUND)**/
.build();
notification.flags = notification.flags | Notification.FLAG_ONGOING_EVENT | Notification.FLAG_NO_CLEAR | Notification.FLAG_FOREGROUND_SERVICE | Notification.FLAG_HIGH_PRIORITY | Notification.FLAG_AUTO_CANCEL;
startForeground(notification_id, notification);
}
// Android8.0以后展示Notification需要创建渠道
private void createNotificationChannel() {
if (Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
// 如果设置成 NotificationManager.IMPORTANCE_HIGH 或者 NotificationManager.IMPORTANCE_DEFAULT 的话会出现提示音,而且无法取消
NotificationChannel channel = new NotificationChannel(notificationChannelId, notificationChannelName, NotificationManager.IMPORTANCE_LOW);
getNotificationManager().createNotificationChannel(channel);
}
}
// Notification管理器
private NotificationManager getNotificationManager() {
if (manager == null) {
manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
}
return manager;
}
// Android8.0以后的版本使用此方法启动Notification
private void showHighNotification() {
if (Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
Notification notification = new Notification.Builder(context, notificationChannelId)
.setContentTitle("买卖客户端")
.setContentText("正在运行中...")
/**点击事件监听器**/
.setContentIntent(PendingIntent.getBroadcast(context, 0, new Intent(ConstantValues.FOREGROUND_NOTIFICATION_CLICKED), 0))
/**消失的监听器**/
.setDeleteIntent(PendingIntent.getBroadcast(context, 0, new Intent(ConstantValues.FOREGROUND_NOTIFICATION_DISMISS), 0))
.setLargeIcon(BitmapFactory.decodeResource(context.getResources(), R.mipmap.ic_launcher))
.setSmallIcon(R.mipmap.ic_launcher) //设置小图标,4.x在右边,5.x在左边
/**通知产生的时间,会在通知信息里显示**/
.setWhen(System.currentTimeMillis())
.setShowWhen(true)
/**设置该通知优先级**/
.setPriority(Notification.PRIORITY_MAX)
/**设置这个标志当用户单击面板就可以让通知将自动取消**/
.setAutoCancel(false)
/**设置他为一个正在进行的通知。他们通常是用来表示一个后台任务,用户积极参与(如播放音乐)或以某种方式正在等待,因此占用设备(如一个文件下载,同步操作,主动网络连接)**/
.setOngoing(true)
/**向通知添加声音、闪灯和振动效果的最简单、最一致的方式是使用当前的用户默认设置,使用defaults属性,可以组合:**/
/**.setDefaults(Notification.DEFAULT_VIBRATE or Notification.DEFAULT_SOUND)**/
.build();
notification.flags = notification.flags | Notification.FLAG_ONGOING_EVENT | Notification.FLAG_NO_CLEAR | Notification.FLAG_FOREGROUND_SERVICE | Notification.FLAG_HIGH_PRIORITY | Notification.FLAG_AUTO_CANCEL;
startForeground(notification_id , notification);
}
}
// 隐藏Notification
public void hideNotification() {
// 删除通道
if (Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
if (getNotificationManager().getNotificationChannel(notificationChannelId) != null) {
getNotificationManager().cancel(notification_id);
getNotificationManager().deleteNotificationChannel(notificationChannelId);
}
}
}
@Override
public void onDestroy() {
super.onDestroy();
// 停止前台服务--参数:表示是否移除之前的通知
stopForeground(true);
}
}
在Application里面对Service进行绑定,然后在绝大部分页面(最好是BaseActivity)的OnResume方法里面调用Application里面的方法校验Service是否存活,这样就基本上保证Service不会被杀掉了
import android.app.Application;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Build;
import android.os.IBinder;
public class App extends Application {
private static Context context;
private static BuySellServiceConnection serviceConnection;
private static BuySellService serviceController;
@Override
public void onCreate() {
super.onCreate();
context = App.this;
}
public static Context getContext() {
return context;
}
// 隐藏服务的Notification
public static void hideServiceNotification() {
if (serviceController != null) {
serviceController.hideNotification();
}
}
// 校验Service的存活状态
public static void checkService() {
if (context != null) {
// 判定服务是否仍然在后台运行
boolean serviceRunning = ServiceUtil.isServiceRunning(BuySellService.class.getName(), context);
if (!serviceRunning) {
Intent buySellIntent = new Intent(context.getApplicationContext(), BuySellService.class);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
context.startForegroundService(buySellIntent );
} else {
context.startService(buySellIntent );
}
if (serviceConnection == null) {
serviceConnection = new BuySellServiceConnection();
}
// 绑定当前服务
context.bindService(new Intent(context, BuySellService.class), serviceConnection, Context.BIND_IMPORTANT);
}
}
}
/**
* 绑定连接需要ServiceConnection
*/
static class BuySellServiceConnection implements ServiceConnection {
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
// 这里可以通过IBinder获取到在Service的onBind方法里面传递过来的Binder对象
// serviceController = ProcessConnection.Stub.asInterface(service);
if (service instanceof BuySellService.BuySellBinder) {
serviceController = ((BuySellService.BuySellBinder) service).getService();
}
}
@Override
public void onServiceDisconnected(ComponentName name) {
// 服务被干掉;连接断掉的时候走此回调
checkService();
}
}
}
最后,在登录完毕之后,执行App.checkService(),然后在LoginActivity的OnDestory方法里面执行App.hideServiceNotification() 就行了,下次打开,可以在SplashActivity的OnCreate中校验当前是否登录成功,成功的话SplashActivity的OnCreate中执行App.checkService(),在SplashActivity的OnDestory方法里面执行App.hideServiceNotification() 就行了;如果要做保活的话,可以在BaseActivity的OnResume里面执行App.checkService(),在BaseActivity的OnDestory方法里面执行App.hideServiceNotification()