java - 从 Activity 的 java 类 npt 调用 Android 通知

Question

如何从 Java 类开始通知？我从一个 Activity 开始通知但是当我尝试从 java 类中执行它时它不起作用，因为它需要一个上下文(这指的是我的类上下文)这是我的函数代码，它从 Activity 开始通知:

 public  void sendNotification(){
    NotificationCompat.Builder mBuilder =  new NotificationCompat.Builder(this)
                        .setSmallIcon(R.mipmap.ic_camera)
                        .setContentTitle("Someone on your door")
                        .setContentText("Open the camera to see!");

    // Creates an explicit intent for an Activity in your app
        Intent resultIntent = new Intent(this, CameraActivity.class);

// The stack builder object will contain an artificial back stack for the
// started Activity.
// This ensures that navigating backward from the Activity leads out of
// your application to the Home screen.
        TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
// Adds the back stack for the Intent (but not the Intent itself)
        stackBuilder.addParentStack(CameraActivity.class);
// Adds the Intent that starts the Activity to the top of the stack
        stackBuilder.addNextIntent(resultIntent);
        PendingIntent resultPendingIntent =
                stackBuilder.getPendingIntent(
                        0,
                        PendingIntent.FLAG_UPDATE_CURRENT
                );
        mBuilder.setContentIntent(resultPendingIntent);
        NotificationManager mNotificationManager = (NotificationManager)      this.getSystemService(Context.NOTIFICATION_SERVICE);
    // mId allows you to update the notification later on.
        mNotificationManager.notify(CAMERA_NOTIFICATION, mBuilder.build());

    }

预先感谢您的帮助

Answer 1

为您的 java 类创建一个参数化的构造函数，将 Context 作为参数并从您的 Activity 中调用它。你如何从 Activity 中调用你的 java 类。您可能通过使其对象 n 调用默认构造函数来调用您的 java 类，我猜是这样的:

错误的方式

JavaClass obj = new JavaClass();

正确的方式

`JavaClass obj = new JavaClass(MainActivity.this); // MainActivity.this is` context