如何使用处理程序将消息从一个线程发送到fargment线程

Question

我想使用处理程序将一些消息从一个线程发送到另一个线程。但实际上不知道如何实现它。在下面的代码中，我想将消息从广播接收器类发送到片段。但我不知道如何实现这个。

片段分节代码：

Calendar calendar= Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.set(Calendar.HOUR_OF_DAY,16);
calendar.set(Calendar.MINUTE,42);
calendar.set(Calendar.SECOND,0);
Intent intent =new Intent(getContext(),NotificationActivity.class);
intent.putExtra("id",R.id.notification_imageView);
PendingIntent pendingIntent =  
PendingIntent.getBroadcast(getContext(),100,intent,PendingIntent.FLAG_UPDATE_CURRENT);
AlarmManager alarmManager=(AlarmManager) getActivity().getSystemService(ALARM_SERVICE);
System.out.println("DEBUG==> Instantiating Alarm Manager Service");
alarmManager.setRepeating(AlarmManager.RTC_WAKEUP,calendar.getTimeInMillis(),1000 * 60 * 
02,pendingIntent);

BroadcastReceiever 类 --ClassNotificationActivity.class

   public class NotificationActivity extends BroadcastReceiver {
   private View view;
   @Override
   public void onReceive(Context context, Intent intent) {
   ImageView img;
   System.out.println("DEBUG==> Page Notification Activity is being loaded");
   View view = View.inflate(context, R.layout.Samplelayout, null);
   img = view.findViewById(R.id.imageview);
   System.out.println("DEBUG==> Loading bulb Image for Animation"+img);
   System.out.println("DEBUG==> Loading bulb Image for Animation");
   Animation animation = new AlphaAnimation((float) 0.5, 0); // Change alpha from fully visible to 
   invisible
   animation.setDuration(500); // duration - half a second--2 minutes
   animation.setRepeatCount(200);
   img.startAnimation(animation);
    }
      }

Manifest.xml

  <uses-permission android:name="android.permission.INTERNET" />
  <uses-permission android:name="android.permission.SET_ALARM" />

  <receiver  android:name=".view.ui.NotificationActivity" />

Samplelayout.xml：

   <LinearLayout
            android:id="@+id/linearLayout"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:background="@color/red"
            android:gravity="center_horizontal"
            android:orientation="vertical">

            <ImageView
                android:id="@+id/imageview"
                android:layout_width="70dp"
                android:layout_height="64dp"
                android:layout_margin="20dp"
                android:src="@drawable/Dumble"
                android:tint="@android:color/white"
                tools:layout_editor_absoluteX="32dp"
                tools:layout_editor_absoluteY="32dp" />


        </LinearLayout>

Answer 1

在onResume() 中注册您的广播接收器。

override fun onResume() {
        super.onResume()
        registerReceiver(this, IntentFilter("com.my.app.test_br"))
    }

在onPause() 确保注销接收者

override fun onPause() {
        super.onPause()
        unregisterReceiver(this)
    }

请务必注意我用于 IntenFilter 的值。这将是其他类如何指定它们发送到哪些广播接收器的方式。

从发送广播的类中，初始化你的广播 Intent（注意用于 Intent 参数的值与注册广播接收器时使用的值相同）

    private val timerIntent = Intent(com.my.app.test_br)

然后发送广播

sendBroadcast(timerIntent)