Secure Connection API

找到遠端裝置後，系統會呼叫 handleIntent 函式， 即可開始在用戶端之間傳遞資料。本節將 保持安全連線的四個重要步驟

• 開啟連結
• 接受連線
• 傳送和接收資料
• 關閉連線

開啟連結

如要建立連線以接收遠端裝置的資料，請使用 先前接收的參與者物件，並指定 CHANNEL_NAME：

KotlinJava

participant
  .openConnection(CHANNEL_HELLO)
  .onFailure { /* handle failure */}
  .getOrNull()
  ?.let { connection ->
    connection.send("Hello, world".toByteArray(UTF_8)).onFailure { /* handle failure */}
  }

public void openConnection(Participant participant) {
  Futures.addCallback(
      participant.openConnectionFuture(CHANNEL_HELLO),
      new FutureCallback<RemoteConnection>() {
        @Override
        public void onSuccess(RemoteConnection remoteConnection) {
          // use remoteConnection object to pass data, e.g.:
          sendDataToRemoteConnection(remoteConnection);
        }

        @Override
        public void onFailure(Throwable t) {
          // handle error opening a remote connection
        }
      },
      mainExecutor);
}

private void sendDataToRemoteConnection(RemoteConnection remoteConnection) {
  Futures.addCallback(
      remoteConnection.sendFuture("Hello, world".getBytes()),
      new FutureCallback<Void>() {
        @Override
        public void onSuccess(Void result) {
          // data sent successfully
        }

        @Override
        public void onFailure(Throwable t) {
          // handle error
        }
      },
      mainExecutor);
}

接受、傳送/接收及關閉連線

安全連線會要求接收裝置接受傳入連線 才能接收資料如要接受遠端連線，請使用下列方式 程式碼片段：

KotlinJava

suspend fun acceptIncomingConnection(participant: Participant) {
  val connection = participant.acceptConnection(CHANNEL_HELLO).getOrThrow()
  connection.registerReceiver(
    object : ConnectionReceiver {
      override fun onMessageReceived(remoteConnection: RemoteConnection, payload: ByteArray) {
        displayMessage(payload.toString(UTF_8))
      }

      override fun onConnectionClosed(
        remoteConnection: RemoteConnection,
        error: Throwable?,
        reason: String?
      ) {
        // handle connection closure
      }
    }
  )
}

public void acceptIncomingConnection(Participant participant) {
  // Registers call back to accept incoming remote connection
  Futures.addCallback(
      participant.acceptConnectionFuture(CHANNEL_HELLO),
      new FutureCallback<>() {
        @Override
        public void onSuccess(RemoteConnection result) {
          receiveData(result);
        }

        @Override
        public void onFailure(Throwable t) {
          // handle connection error
        }
      },
      mainExecutor);
}

private void receiveData(RemoteConnection remoteConnection) {
  remoteConnection.registerReceiver(
      new ConnectionReceiver() {
        @Override
        public void onMessageReceived(RemoteConnection remoteConnection, byte[] payload) {
          displayMessage(new String(payload, UTF_8));
        }

        @Override
        public void onConnectionClosed(
            RemoteConnection remoteConnection,
            @Nullable Throwable error,
            @Nullable String reason) {
          // handle connection closure
        }
      });
}