private async void ResultCharacteristic_ReadRequestedAsync(GattLocalCharacteristic sender, GattReadRequestedEventArgs args)
{
// BT_Code: Process a read request.
using (args.GetDeferral())
{
// Get the request information. This requires device access before an app can access the device's request.
GattReadRequest request = await args.GetRequestAsync();
if (request == null)
{
// No access allowed to the device. Application should indicate this to the user.
rootPage.NotifyUser("Access to device not allowed", NotifyType.ErrorMessage);
return;
}
var writer = new DataWriter();
writer.ByteOrder = ByteOrder.LittleEndian;
writer.WriteInt32(resultVal);
// Can get details about the request such as the size and offset, as well as monitor the state to see if it has been completed/cancelled externally.
// request.Offset
// request.Length
// request.State
// request.StateChanged += <Handler>
// Gatt code to handle the response
request.RespondWithValue(writer.DetachBuffer());
}
}
private async void WifiListCharacteristic_ReadRequestedAsync(GattLocalCharacteristic sender, GattReadRequestedEventArgs args)
{
using (args.GetDeferral())
{
// Get the request information. This requires device access before an app can access the device's request.
GattReadRequest request = await args.GetRequestAsync();
if (request == null)
{
// No access allowed to the device. Application should indicate this to the user.
return;
}
var writer = new DataWriter();
var result = JsonConvert.SerializeObject(
new WIfiNetworkPayload
{
AvailableAdapters =
this.WiFiAdapter.NetworkReport.AvailableNetworks.Select(x => new WifiNetwork {
Ssid = x.Ssid
})
});
writer.WriteString(result);
//var wifiAdapters =
//writer.WriteString("{ \"AvailableAdapters\": [{ \"Ssid\": \"ilab\" }, { \"Ssid\": \"uqconnect\" }] }");
// Gatt code to handle the response
request.RespondWithValue(writer.DetachBuffer());
}
}
/// <summary>
/// Read request callback to update the value
/// </summary>
/// <param name="sender"></param>
/// <param name="args"></param>
protected override bool ReadRequested(GattSession session, GattReadRequest request)
{
DataWriter writer = new DataWriter();
int maxPayloadSize = session.MaxPduSize - 1;
// make sure our source data is bigger than a single read request to make sure a ReadBlobRequest is done
if (longCharacteristicData.Length < maxPayloadSize)
{
// This should not be required as the server should only be processing one request at a time
// but it's better to be safe than sorry
lock (dataLock)
{
longCharacteristicData = new byte[(int)(maxPayloadSize * 2.5)];
for (int i = 0; i < longCharacteristicData.Length; i++)
{
longCharacteristicData[i] = (byte)(i % 10);
}
}
}
// finish getting the read request
int offset = (int)request.Offset;
// calculate the size of the data we send back
int chunk = Math.Min(maxPayloadSize, longCharacteristicData.Length - offset);
Debug.WriteLine($"UpdateValue: payloadSize: {maxPayloadSize}, chunk {chunk}");
// prep the data we send back
var readValue = String.Empty;
var buffer = new byte[chunk];
buffer.Initialize();
// copy from source to target
Array.Copy(longCharacteristicData, longCharacteristicReadOffset, buffer, 0, chunk);
// write to our internal Value which will be used to send back the data
writer.WriteBytes(buffer);
readValue = buffer.BytesToString();
Debug.WriteLine("MicrosoftReadLongCharacteristic: Read request value: {readValue}");
// Update our characteristics value.
Value = writer.DetachBuffer();
// Respond back to the caller.
request.RespondWithValue(Value);
return(true);
}
private async void RossCharacteristic_ReadRequestedAsync(GattLocalCharacteristic sender, GattReadRequestedEventArgs args)
{
using (args.GetDeferral())
{
// Get the request information. This requires device access before an app can access the device's request.
GattReadRequest request = await args.GetRequestAsync();
if (request == null)
{
// No access allowed to the device. Application should indicate this to the user.
return;
}
var writer = new DataWriter();
writer.WriteString("1.5.14.0");
// Gatt code to handle the response
request.RespondWithValue(writer.DetachBuffer());
}
}
protected override bool ReadRequested(GattSession session, GattReadRequest request)
{
UpdateCurrentTimeValue();
request.RespondWithValue(Value);
return(true);
}