Nearby connections 2.0 simple files exchange app - google-play-services

Question

I'm trying to write simple android file exchange application, mostly using snippets from https://developers.google.com/nearby/connections/android/exchange-data and Walkietalkie app.
But I'm stuck on transferring File payload second sendPayload, onPayloadTransferUpdate called only on sending side. Discovering, advertising, connecting to the endpoint, everything works fine. The sender is "sending", but Reciever gets only string message with id and filename and waits (onPayloadTransferUpdate called only 2 times for the first sendPayload) and then nothing, disconnects after sender finished transferring.
public void sendFile(String uri) {
File file = new File(uri);
if (file.exists() && mEstablishedConnections.values().size() > 0) {
for (Endpoint endpoint : mEstablishedConnections.values()) {
try {
// Open the ParcelFileDescriptor for this URI with read access.
ParcelFileDescriptor pfd = getContentResolver().openFileDescriptor(Uri.fromFile(file), "r");
Payload filePayload = Payload.fromFile(pfd);
// Construct a simple message mapping the ID of the file payload to the desired filename.
String payloadFilenameMessage = filePayload.getId() + ":" + Uri.fromFile(file).getLastPathSegment();
// Send this message as a bytes payload.
Nearby.Connections.sendPayload(mGoogleApiClient,
endpoint.getId(),
Payload.fromBytes(payloadFilenameMessage.getBytes("UTF-8")));
// Finally, send the file payload.
Nearby.Connections.sendPayload(mGoogleApiClient,
endpoint.getId(),
filePayload);
} catch (FileNotFoundException | UnsupportedEncodingException e) {
e.printStackTrace();
}
}
} else {
Log.e(TAG, "sendFile: EstablishedConnections == 0");
}
}
private final PayloadCallback mPayloadCallback = new PayloadCallback() {
#Override
public void onPayloadReceived(String endpointId, Payload payload) {
Log.d(TAG, String.format("onPayloadReceived(endpointId=%s, payload=%s)", endpointId, payload));
try {
if (payload.getType() == Payload.Type.BYTES) {
Log.d(TAG, "onPayloadReceived: Payload.Type.BYTES");
String payloadFilenameMessage = new String(payload.asBytes(), "UTF-8");
Log.d(TAG, "onPayloadReceived: BYTES " + payloadFilenameMessage);
addPayloadFilename(payloadFilenameMessage);
} else if (payload.getType() == Payload.Type.FILE) {
// Add this to our tracking map, so that we can retrieve the payload later.
incomingFilePayloads.put(payload.getId(), payload);
Log.d(TAG, "onPayloadReceived: Payload.Type.FILE");
} else if (payload.getType() == Payload.Type.STREAM) {
//payload.asStream().asInputStream()
Log.d(TAG, "onPayloadReceived: Payload.Type.STREAM");
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
#Override
public void onPayloadTransferUpdate(String endpointId, PayloadTransferUpdate update) {
Log.d(TAG, String.format("onPayloadTransferUpdate(endpointId=%s, update=%s)",
endpointId, update));
switch(update.getStatus()) {
case PayloadTransferUpdate.Status.IN_PROGRESS:
break;
case PayloadTransferUpdate.Status.SUCCESS:
Log.d(TAG, "onPayloadTransferUpdate: SUCCESS");
Payload payload = incomingFilePayloads.remove(update.getPayloadId());
if (payload != null && payload.getType() == Payload.Type.FILE) {
// Retrieve the filename that was received in a bytes payload.
String newFilename = filePayloadFilenames.remove(update.getPayloadId());
java.io.File payloadFile = payload.asFile().asJavaFile();
// Rename the file.
payloadFile.renameTo(new File(payloadFile.getParentFile(), newFilename));
}
break;
case PayloadTransferUpdate.Status.FAILURE:
Log.d(TAG, "onPayloadTransferUpdate: FAILURE");
break;
}
}
};
Is there a working example apart from google sample walkietalkie?
Sender
D/ShareService: sendFile: filename message -7668342386822656500:a73ecba18dc6c8506ed89c1ed47c9948.mp4
D/ShareService: onPayloadTransferUpdate(endpointId=osUc, update=com.google.android.gms.nearby.connection.PayloadTransferUpdate#e16fc0a8)
D/ShareService: onPayloadTransferUpdate: 57
D/ShareService: onPayloadTransferUpdate: 1048576
D/DiscoveryActivity: onNext: ShareState{state='Sending ', stateCode=800}
D/ShareService: onPayloadTransferUpdate(endpointId=osUc, update=com.google.android.gms.nearby.connection.PayloadTransferUpdate#813731ce)
D/ShareService: onPayloadTransferUpdate: 1055744
D/DiscoveryActivity: onNext: ShareState{state='Sending ', stateCode=800}
D/ShareService: onPayloadTransferUpdate(endpointId=osUc, update=com.google.android.gms.nearby.connection.PayloadTransferUpdate#81372a4c)
11-01 07:35:20.790 D/ShareService: onPayloadTransferUpdate: SUCCESS
11-01 07:35:41.587 D/ShareService: disconnectedFromEndpoint(endpoint=Endpoint{id=osUc, name=87389})
11-01 07:35:41.587 D/ShareService: onEndpointDisconnected
Reciever
D/ShareService: onConnectionResponse(endpointId=ABVq, result=com.google.android.gms.nearby.connection.ConnectionResolution#9edd5e3)
D/ShareService: connectedToEndpoint(endpoint=Endpoint{id=ABVq, name=08043})
D/ShareService: onEndpointConnected
D/ShareService: stopDiscovering
D/ShareService: stopAdvertising
D/ShareService: onPayloadReceived(endpointId=ABVq, payload=com.google.android.gms.nearby.connection.Payload#516155e)
D/ShareService: onPayloadReceived: Payload.Type.BYTES
D/ShareService: onPayloadReceived: BYTES -7668342386822656500:a73ecba18dc6c8506ed89c1ed47c9948.mp4
D/ShareService: onPayloadTransferUpdate(endpointId=ABVq, update=com.google.android.gms.nearby.connection.PayloadTransferUpdate#ba6f47ac)
D/ShareService: onPayloadTransferUpdate: 57
D/ShareService: onPayloadTransferUpdate(endpointId=ABVq, update=com.google.android.gms.nearby.connection.PayloadTransferUpdate#ba6f402a)
11-01 08:10:52.525 D/ShareService: onPayloadTransferUpdate: SUCCESS
11-01 08:11:12.355 D/ShareService: disconnectedFromEndpoint(endpoint=Endpoint{id=ABVq,name=08043})
D/ShareService: onEndpointDisconnected
onPayloadTransferUpdate: SUCCESS for first string transfer
delay
Payload bytePayload = outgoingPayloads.remove(update.getPayloadId());
if (bytePayload != null && bytePayload.getType() == Payload.Type.BYTES) {
if (endpnt != null && filePayload != null) {
try {
Thread.sleep(10000);
} catch (InterruptedException e) {
e.printStackTrace();
}
Nearby.Connections.sendPayload(mGoogleApiClient,
endpnt.getId(),
filePayload);
}
}
file:///data/data/com.package.name/files/folder/a73ecba18dc6c8506ed89c1ed47c9948.mp4
sources https://github.com/salexwm/FilesExchange

Answer 1

I can provide a working example if you need one, but you almost have it. Some pointers:
Send the FILE payload only after the BYTE header has fully sent, in onPayloadTransferUpdate(SUCCESS). Order isn't guaranteed for payloads of different types.
Don't disconnect until you get onPayloadTransferUpdate(SUCCESS) for the FILE payload. If you disconnect during transmission, it won't fully send.
You should be doing Uri.parse(uri), not Uri.fromFile(new File(uri)).