Connect to peripheral in didSelectRowAtIndexPath - objective-c

Question

I am developing an app using CoreBluetooth. I am able to discover devices from the app and show their names in the table view. I am facing a problem with requirements below:
When used for the first time, the user selects a peripheral from the list. Connection should be established with the peripheral using the Bluetooth Serial Port Profile (SPP). Discovery and connection is simple and accomplished with a single click, minimizing user interaction.
Once a connection has been established between the peripheral device and the app, the app remembers the device and always seeks and connects to it for all subsequent uses.
I have written the following code for this as below for scanning and discovering
- (void)scan
{
NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithBool:NO], CBCentralManagerScanOptionAllowDuplicatesKey, nil];
NSLog(#"options are %#",options);
[self.centralManager scanForPeripheralsWithServices:nil
options:nil];
_txtLogMessage.text = [NSString stringWithFormat:#"%# \n %#",_txtLogMessage.text,#"Scanning started"];
NSLog(#"Scanning started");
}
- (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral
*)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI
{
[central connectPeripheral:peripheral options:nil];
self.discoveredPeripheral = peripheral;
_logData = [NSString stringWithFormat:#"Did discover peripheral. peripheral: %# rssi: %#, UUID: %# advertisementData: %# ", peripheral, RSSI, peripheral.UUID, advertisementData];
NSLog(#"%#",_logData);
[_periferalDevices addObject:peripheral.name];
[_tableView reloadData];
}
for connecting the device
- (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral
{
peripheral.delegate = self;
[self.discoveredPeripheral discoverServices:nil];
NSLog(#"Peripheral Connected");
NSLog(#" started time is %#",_timestring);
//[self.centralManager stopScan];
NSLog(#"Scanning stopped");
[self.data setLength:0];
[peripheral discoverServices:nil];
[peripheral discoverServices:#[[CBUUID UUIDWithString:TRANSFER_SERVICE_UUID]]];
}
in table view cell for row at index path aim able to get the data to view but aim facing problem in connecting to a peripheral while particular row is selected in the table view
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath*)indexPath{
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:CellIdentifier];
}
cell.textLabel.text = [_periferalDevices objectAtIndex:indexPath.row];
return cell;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
_discoveredPeripheral.delegate = self;
[self.centralManager connectPeripheral:[_periferalDevices objectAtIndex:indexPath.row]
options:nil];
NSLog(#"discovered peripheral is %#",[_periferalDevices objectAtIndex:indexPath.row]);
NSString *datstr=[_discoveredPeripheral valueForKey:#"identifier"];
NSLog(#"value for key is ........%#",datstr);
}

Answer 1

The errors that you get when you try to use the peripheral object stems from the fact that you added the name of the peripheral to your array rather than the peripheral, itself. Thus, replace
[_periferalDevices addObject:peripheral.name];
With
[_periferalDevices addObject:peripheral];
And, obviously, you'll have to fix wherever you took advantage of just inserting the name. For example, your cellForRowAtIndexPath bears a line that says:
cell.textLabel.text = [_periferalDevices objectAtIndex:indexPath.row];
You'd probably want to replace that with something like:
CBPeripheral *peripheral = _periferalDevices[indexPath.row];
cell.textLabel.text = peripheral.name;
Your didDiscover... is connecting immediately. It probably shouldn't. You should probably only try connecting to the device the user selected. This could cause problems if you try to connect again (I don't know what it does if you try to connect twice). Your didSelectRow... connects on the ones the user chooses, so you should probably leave it at that.
You say "am facing problem connecting". So, what precisely did didFailToConnectPeripheral report?
As an aside, I'm unclear why you're calling discoverServices twice, too. Either discover all services (slow) or discover just the particular service, but you probably don't have to do both.
My original answer (based upon original code sample) is below.
You have code that says:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
NSString *cellText = cell.textLabel.text;
if([cellText isEqualToString:#""])
{
}
else
{
UIAlertView *alert=[[UIAlertView alloc] initWithTitle:#"Connected to "
message:cellText delegate:self cancelButtonTitle:#"ok"
otherButtonTitles: nil];
[alert show];
}
_discoveredPeripheral.delegate = self;
[self.centralManager connectPeripheral:_discoveredPeripheral options:nil];
NSLog(#"discovered peripheral is %#", _discoveredPeripheral);
NSString *datstr = [_discoveredPeripheral valueForKey:#"identifier"];
NSLog(#"value for key is ........%#", datstr);
}
You are retrieving the information on the selected cell (though Hot Licks is correct, you should be going to your model, not to the view for that information), retrieving the cellText, but you proceed to use _discoveredPeripheral, which is some variable that bears no obvious relation to the cell the user just selected.
You want to maintain your model of the array of peripherals, and when a user taps on the cell, use the indexPath.row to look up the peripheral in your model array, and use that CBPeripheral in your connection code.