I have a phone app which gets launched on boot and at that point attempts to make a connection to a corresponding app on a wearable device.
However if at that time there isn't a paired wearable then the connection will fail (Wearable.NodeApi.getConnectedNodes won't return anything).
Therefore my app will need to re-attempt the connection at a later time. My question there is this: is there something my code can subscribe to to get a callback when the phone gets paired with a wearable?
the NodeApi.NodeListener as the method onPeerConnected(Node peer), which looks like what you are looking for. It is invoked when a new peer is reachable from the node, where the callback is invoked
Related
I am tring to setup WIFI P2P on 2 devices using
manager.addLocalService(channel, service, ActionListener)
and then connect both devices using
manager.connect(channel, config, ActionListener).
I would like to know which method is called before the popup to accept/reject connection is shown on the target device. All I was able to find was onConnectionInfoAvailable(WifiP2pInfo p2pInfo), but it is called after the connection is established.
I basically want to receive the "instance name" of the device trying to connect to me using WIFI P2P and then reject the connection request without showing system dialog(that allows the user to accept/reject connection).
I can't anything that can help me do this on docs or any other place. If anyone knows how to do it or can point me in the right direction then please let me know.
I solved it. I can put the instancename and devicename (of device I want to connect to) in Map that is passed when setting up service. From other device I can retrieve map of all devices available using this and find the instancename of one I need.
In my application I need to start some BLE scans, get the results and then show them in a list or in a grid.
When i start the scan my device start to look for advertisements basing on which ScanFilters I wrote.
Every time a Pheriperal is found I the application trigger the scan callback method and i can add the new device into the list.
If i got an error the app trigger the callback method and i can tell the user about the broblem.
Example
Imagine the Scan going on for 30s.
At the moment it starts i get 3 Ble Pheriperal.
At second 15 one of them stop to advertise and turn bluetooth off.
At the end of the scan my list will have 3 Ble devices but i will not be able to connect to one of them.
How do I know which of them is the one which turned off?
Where do i get his status?
Thanks for the help.
You can try this, technically it is possible as per the documentation. in onScanResult callback, check for the callbackType parameter. If it is CALLBACK_TYPE_MATCH_LOST then get the device from the results and remove it from your cache.
using the android 4.4 BLE APIs on my Nexus7, i'm able to successfully interact with a peripheral BLE device -- connect, disconnect, read, write....
if however an active connection breaks for whatever reason (in this case, the peripheral is reset), i observe the following behavior....
my peripheral (by design) begins advertising after any active connection is terminated (for whatever reason); i can see this via my bluetooth packet sniffer....
i receive the onConnectionStateChanged callback as expected in my android app, at which point i invoke close() on my active BluetoothGatt instance; this is the same procedure i follow during a "normal" disconnect initiated from the client...
shortly after this, the android BLE stack tries to re-connect to the same peripheral; through the packet sniffer i can see the BLE connection request going out over the air...
my app, however, did not initiate this re-connection; indeed, i see no information from any bluetooth log suggesting this even happened!!!!
is there some "mode" in the BLE stack where it attempts to re-establish busted connections automatically???
thanks....
This happens on various Android phones whether the autoConnect flag is set to false or true.
Couldn't yet find a complete solution, it seems as the android BLE stack is spontaneously re-initiating the connection once it is getting the advertising signal again, just ignoring that it was the app that disconnected on purpose...
A partial solution may involve not using the BluetoothGatt.connect() method as explained here:
https://stackoverflow.com/a/23749770/4144487
So, a sample connect method can look like:
void connect(Context context) {
if (mGatt != null) {
mGatt.close();
}
mGatt = mDevice.connectGatt(context, false, callback);
}
To explain the importance of this issue, when it happens the peripheral thinks it is connected and my "real" app can't find it any more. At some phones like Galaxy S3 and Redmi note 3 I found that closing the bluetooth switch from the notification bar is "releasing" the peripheral and allowing me to discover the device. At others like Nexus 5x only a phone reboot will do the trick.
I've observed this happening if you use autoConnect=true when calling BluetoothGatt#connectGatt(). Generally I've found that it is best to use autoConnect=false, but with some devices you simply cannot connect unless you use true, so I usually do both. I try false first and if that fails then use true and then the behavior you're describing is something you simply have to work around.
I am developing a simple wifiDirect chat app.My app does peer searching and once peer's list is available one can select a particular device, the one to connect with. Then my code calls connect() which sends a notification to the other device (2nd phone) about connection (default). Once the second phone agrees to the connection then 1st phone becomes group owner while second phone running my app does nothing.
So my question is do I need to call connect() on both devices? Also when is this intent action WIFI_P2P_THIS_DEVICE_CHANGED_ACTION broadcast?
Need help, read android.developers.com and other official sites but couldn't figure out.
No, you only need to call connect() on one device. Note that this does not mean that the device that calls connect() will be the group owner. The system will decide the group owner itself. You can only suggest your preference through config.groupOwnerIntent = x; where x is from 0 to 15, 0 representing least intention to become owner while 15 represents the highest.
WIFI_P2P_THIS_DEVICE_CHANGED_ACTION event will be fired when the status of the device has changed.
Use the following code to fetch the updated details of the device.
(WifiP2pDevice)intent.getParcelableExtra(WifiP2pManager.EXTRA_WIFI_P2P_DEVICE));
Finally got my device (based on TI's CC2541) to work with my phone (a prototype/non-commercial-yet phone running Android 4.3). I can scan, discover, connect and get notifications successfully. However, when I disconnect (calling BluetoothGatt.disconnect()), the onConnectionStateChange callback is called with newState=STATE_DISCONNECTED (as expected) but then immediately called again with newState=STATE_CONNECTED.
The connection is definitely terminated so I'm not sure why I'm getting the 2nd onConnectionStateChange call. Has anyone experienced anything similar?
Check the status given to you in onConnectionStateChange; if the status isn't 0 (OK) then you didn't actually get a connection. I've found a number of occasions where I get the CONNECTED message but the status was indicating something else was happening.