如何在不打开应用的情况下实现 Android 通知操作？

此示例演示了如何在不打开应用的情况下实现 Android 通知操作。

步骤 1 - 在 Android Studio 中创建一个新项目，转到文件 ⇒ 新建项目，并填写所有必需的详细信息以创建新项目。

步骤 2 - 将以下代码添加到 res/layout/activity_main.xml 中。

<? xml version = "1.0" encoding = "utf-8" ?>
<RelativeLayout 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:padding = "16dp"
   tools:context = ".MainActivity" >
   <Button
      android:onClick= "createNotification"
      android:text= "create notification"
      android:layout_centerInParent= "true"
      android:layout_width= "match_parent"
      android:layout_height= "wrap_content" />
</RelativeLayout>

步骤 3 - 将以下代码添加到 src/MainActivity 中。

package app.tutorialspoint.com.notifyme ;
import android.app.NotificationChannel ;
import android.app.NotificationManager ;
import android.app.PendingIntent ;
import android.content.Intent ;
import android.os.Bundle ;
import android.support.v4.app.NotificationCompat ;
import android.support.v7.app.AppCompatActivity ;
import android.view.View ;
public class MainActivity extends AppCompatActivity {
   public static final String NOTIFICATION_CHANNEL_ID = "10001" ;
   private final static String default_notification_channel_id = "default" ;
   @Override
   protected void onCreate (Bundle savedInstanceState) {
      super .onCreate(savedInstanceState) ;
      setContentView(R.layout. activity_main ) ;
   }
   public void createNotification (View view) {
      int NOTIFICATION_ID = ( int ) System. currentTimeMillis () ;
      PendingIntent pendingIntent = PendingIntent. getActivity ( this, 0 , new Intent() , 0 ) ;
      Intent buttonIntent = new Intent( this, NotificationBroadcastReceiver. class ) ;
      buttonIntent.putExtra( "notificationId" , NOTIFICATION_ID) ;
      PendingIntent btPendingIntent = PendingIntent. getBroadcast ( this, 0 , buttonIntent , 0 ) ;
      NotificationManager mNotificationManager = (NotificationManager) getSystemService( NOTIFICATION_SERVICE ) ;
      NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(getApplicationContext() , default_notification_channel_id ) ;
      mBuilder.setContentTitle( "My Notification" ) ;
      mBuilder.setContentIntent(pendingIntent) ;
      mBuilder.addAction(R.drawable. ic_launcher_foreground , "Cancel" , btPendingIntent) ;
      mBuilder.setContentText( "Notification Listener Service Example" ) ;
      mBuilder.setSmallIcon(R.drawable. ic_launcher_foreground ) ;
      mBuilder.setAutoCancel( true ) ;
      mBuilder.setDeleteIntent(getDeleteIntent()) ;
      if (android.os.Build.VERSION. SDK_INT >= android.os.Build.VERSION_CODES. O ) {
         int importance = NotificationManager. IMPORTANCE_HIGH ;
         NotificationChannel notificationChannel = new NotificationChannel( NOTIFICATION_CHANNEL_ID , "NOTIFICATION_CHANNEL_NAME" , importance) ;
         mBuilder.setChannelId( NOTIFICATION_CHANNEL_ID ) ;
         assert mNotificationManager != null;
         mNotificationManager.createNotificationChannel(notificationChannel) ;
      }
      assert mNotificationManager != null;
      mNotificationManager.notify(NOTIFICATION_ID , mBuilder.build()) ;
   }
   protected PendingIntent getDeleteIntent () {
      Intent intent = new Intent(MainActivity. this,
      NotificationBroadcastReceiver. class ) ;
      intent.setAction( "notification_cancelled" ) ;
      return PendingIntent. getBroadcast (MainActivity. this, 0 , intent , PendingIntent. FLAG_CANCEL_CURRENT ) ;
   }
}

步骤 4 - 将以下代码添加到 src/NotificationBroadcastReceiver 中

package app.tutorialspoint.com.notifyme ;
import android.app.NotificationManager ;
import android.content.BroadcastReceiver ;
import android.content.Context ;
import android.content.Intent ;
public class NotificationBroadcastReceiver extends BroadcastReceiver {
   @Override
   public void onReceive (Context context , Intent intent) {
      int notificationId = intent.getIntExtra( "notificationId" , 0 ) ;
      // if you want cancel notification
      NotificationManager manager = (NotificationManager) context.getSystemService(Context. NOTIFICATION_SERVICE ) ;
      manager.cancel(notificationId) ;
   }
}

步骤 5 - 将以下代码添加到 AndroidManifest.xml 中

<? xml version = "1.0" encoding = "utf-8" ?>
<manifest xmlns: android = "http://schemas.android.com/apk/res/android"
   package = "app.tutorialspoint.com.notifyme" >
   <uses-permission android :name = "android.permission.VIBRATE" />
   <uses-permission android :name = "android.permission.RECEIVE_BOOT_COMPLETED" />
   <application
      android :allowBackup = "true"
      android :icon = "@mipmap/ic_launcher"
      android :label = "@string/app_name"
      android :roundIcon = "@mipmap/ic_launcher_round"
      android :supportsRtl = "true"
      android :theme = "@style/AppTheme" >
      <receiver
         android :name = ".NotificationBroadcastReceiver"
         android :enabled = "true"
         android :exported = "true" >
      </receiver>
      <activity android :name = ".MainActivity" >
         <intent-filter>
            <action android :name = "android.intent.action.MAIN" />
            <category android :name = "android.intent.category.LAUNCHER" />
         </intent-filter>
      </activity>
   </application>
</manifest>

让我们尝试运行您的应用程序。我假设您已将您的实际 Android 移动设备连接到您的计算机。要从 Android Studio 运行应用程序，请打开项目中的一个活动文件，然后单击工具栏中的运行图标。选择您的移动设备作为选项，然后检查您的移动设备，它将显示您的默认屏幕