Before the discussion start, i need to provide some info on my background.
I have a android app develop under XAMARIN ANDROID platform. The android app will pair with a ZEBRA printer ZQ521. All the print jobs is send from android device to ZQ521 printer via Bluetooth connections. I have use LINK OS XAMARIN SDK's API to handle the Bluetooth communication between android device and ZEBRA ZQ521. Below is the sample source code i tried.
=======================================================================================================================
public void Print(IConnection connection)
{
string zpl = "^XA^POI^MNN^LL90^PW400^FO20,20^A0N,50,50^FDTEST^FS^XZ";//sample content to print
try
{
connection.Open();
connection.Write(Encoding.UTF8.GetBytes(zpl));
}
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine("Exception:" + e.Message);
}
finally
{
if (connection.IsConnected)
connection.Close();
}
}
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What happen now is whenever i call connection.Close(); to close the bluetooth connection, it took about 5 to 8 seconds to complete the action. This is troublesome to my use case as we need to print on average 300 to 500 print jobs a day. If each print jobs take 5 to 10 secs to complete, our user will need more time to complete 300 to 500 print jobs.
I have decided to redesign how i handle the LINK OS API. Below is the steps
1. I will set my connection object to singleton object (which means i only create the object once).
1. When user start to use our app, i will call connection.Open(); 1 times.
2. I WILL NOT call connection.close() for each print jobs
3. By the end of day i will force my app to reboot the android device so that zebra bluetooth connection is close after user's daily operation ended.
My question is
1. What is the impact if i didn't close the bluetooth connection, if is the concern of memory resources, i have utilize singleton pattern on connection object to ensure the connection is only created once., will that help?