Android SDK sample doesn't display data channel messages from C SDK. How can I display them?

[agrexgh]

Brief

I'd like to use both C SDK and Android SDK,
but this combination has a problem with data channel communication.
As the title says, Android sample doesn't display data channel messages from C SDK sample.
How can I display them?

The version of code

• amazon-kinesis-video-streams-webrtc-sdk-android
  4d1b0ed8dac338c0a8dddfda923a0b176cc50fb8

• amazon-kinesis-video-streams-webrtc-sdk-c
  08e4d294a7466f42033a7aaeacf2521f519749f7 applied the patch below.
  This patch makes C SDK sample to echo back the received data channel messages and show result of sending them.

diff --git a/samples/Common.c b/samples/Common.c
index f1c9f961a..368bd88cb 100644
--- a/samples/Common.c
+++ b/samples/Common.c
@@ -21,6 +21,9 @@ VOID onDataChannelMessage(UINT64 customData, PRtcDataChannel pDataChannel, BOOL
     } else {
         DLOGI("DataChannel String Message: %.*s\n", pMessageLen, pMessage);
     }
+
+    STATUS ret = dataChannelSend(pDataChannel, isBinary, pMessage, pMessageLen);
+    DLOGW("ret = %d", ret);
 }

 VOID onDataChannel(UINT64 customData, PRtcDataChannel pRtcDataChannel)

How to reproduce this issue

1. Launch both sdk samples and connect them to same channel.
2. From Android sample, send a data channel message.

Expected behavior

At 2, Android sample display the data channel message just like the one Android sample sent on the heads-up notification.

Actual behavior

At 2, Android app DOESNOT display them.

Supplement

• I can't tell which SDK sample has the problem.
• With Android SDK sample and JS SDK sample, there is no problem.
  Android sample shows the data channel messages from JS SDK sample on the heads-up notification.

[agrexgh]

I tried
C SDK sample (0be097904010bb53cca44fd6453c2da953ead4d9), which sends data channel message when the C sample receives data channel messages,
and Android SDK sample (4d1b0ed8dac338c0a8dddfda923a0b176cc50fb8) pairs,
but unfortunately Android SDK sample seems not to receive data from C SDK sample.

I'll try to investigate this issue,
but someone, could you give me some help?

[agrexgh]

Android SDK sample creates Data Channel only to send messages, but not this is not to receive messages
(I don't know why but onMessage() method is no op).

And C SDK sample sends and receives messages with this data channel,
but messages sent from C SDK sample is ignored by Android SDK sample.

By the way JS SDK sample is very similar to this.

[ghost]

Do you have any progress on this issue?
And, does this issue occur on iOS SDK?

[sirknightj]

I ran the sample just now. Using Android Master, and C viewer.

As you can see from the screenshot below, data channel messages are shown.

.

However, with C Master and Android viewer, that's when the data channel messages are not displayed.