I'm building an application, it's easy and what I want to do is the following. I want a brainless client and all the work should be done on the server. So I want a way to change windows forms in my server application and not on the client itself.
So when I have an application like blackjack the user presses hit then the hit function on the server get called, he will calculate everything, send the result back to the client and then the client updates it buttons and GUI (like displaying cards, and so on).
Now how do you do this in WCF? I know how to call remote function but I can't get the windows forms part to work (can I add this in the contract, and how?)
Thanks!
Your client should handle all of its own UI. Your service shouldn't have anything to do with the UI.
Instead of having the service handle the UI, just have it send messages back to the client and let the client figure out which UI elements to show or not based on the messages.
So, when the server calculates some result, like BLACKJACK!, it'll send a message indicating that back to the client which will then show the proper UI elements.
Make sense?
Related
I am experimenting with using Reactive Extensions to create a Windows Service.
Essentially what I want is for the Observer to sit on the server, the clients able to create observables and have them pushed to the server, the server informing the client of the progress of the job (not sure how to do this or what mechanism to use to do it), and then when it's done, having the server send the client the return code and output of the program it called. Can this be done? Is it the best way to do what I'm trying to do? If you need any more information, what would you need to know to help me?
This seems back to front. Generally clients know about servers (how to find then and connect). In contrast the Observer pattern (and therefore Rx) is about allowing something to callback to another observer that is does not know about.
In your case I think you simply want to have clients call methods on a server. Potentially these are bound to a single connection/session. The client however maybe an observer of the progress from the server and the final result.
See the Reactive Trader project by the team at Adaptive to see a .NET client server app using Rx.
In our application we have a back-to-back-connection between an operator (client) and a caller, via an ucma-application we built. Now we want to transfer the caller to another operator or number.
This transfer is attended, so we want to keep the call in the client at least until the transfer is completed.
The client application tells the ucma-application to do the transfer. As such, the server makes a transfer on the leg from ucma -> caller. In this scenario, the leg from ucma to the client application remains intact, but we want to receive information about this transfer so that we can show the transfer status in the client application. If the transfer fails, it should also be clear to the operator (it should also be on hold during the time of the transfer, and continue to be on hold even after transfer failed).
Which is the correct way to do this in UCMA?
It's hard to give you advice as there are multiple ways to do what you want depending on what you need to achieve.
I think the main problem is that you are doing the transfer in the middle, you can't tell the Lync Client to go on "hold". Because of this, you can only put the call on hold from the point of view of UMCA application. This means that if you will have to provide your own UI to unhold the call if it fails, maybe from your own Client Application GUI.
What you could do is write a Lync Client SDK controlled Lync Client application. If you have a Lync Client SDK controlled Lync Client, you could remote control the Lync Client to do the transfer, that way you get the standard Lync Client failed transfer UI. If you do this, what is the point of the UCMA application?
If you have to do it from the UCMA point of view, you could:
Provide the UI in your only Client Application (I would think no nice) including controlling the hold status on a failure
Lync Client SDK controlled Lync Client to put the call on Hold that way it's the standard Lync Client way to unhold on failure, then the only need to worry about the display of a failed transfer. Maybe display something in your client application, maybe a send a in call IM from the UCMA application?
See if the Lync Client support BoardWork Extensions (specifically the Remote Control Hold Event Package). If it does then you can remotely put the call on hold, most likely though that it doesn't :(
I know that push notifications are being sent from a backend server. Is it possible to send notification from client itself? My application goes like this: It acquires its position using Location services API. once it enters a specific circle, the trigger calls a callback function. What i want to do is to use the callback function to push a notification to the device. Is there any way to do this?
Thank you very much in advance!
If you just want a notification when the app is active in the background, you can use local notifications: https://github.com/katzer/cordova-plugin-local-notifications. The plug-in Javascript has to be modified somewhat to work with a Worklight app, but with some simple modifications it works great, and allows your app running in the background to raise a notification without going through the server side round trip involved when using push.
That said, I implemented an app that did exactly what you are looking for (in my case, I needed some server side processing to figure out what the text of the push message should be) The geo-fence callback called an adapter, providing it with event details and the device ID. The adapter determined what message to send, and used unicast push to send it back to the device.
You can invoke a procedure in the client side. I tried to invoke in the client side with httpAdapter and its working.
If the notification doesn't need to come from the server, you can also create a service that will run in the background and show a dialogbox once it enters the geofence.
Wondering if there is a better option than a wcf callback.
When processing some data Invoices and printing them and I need to constantly show the user in a winform -"Invoice 1 Printed" invoice 2 printed etc....
I have put together a call back mechanism and all works but wondering if there is a better way of doing this .
Was thinking along the line if 2 services would be better than a callback.
One that loops at server side through the invoices and saves to the database the status ="Printed" and the other the queries it and check if it has printed and return to the user
.
Would that be better than a callback,faster and avoid timeouts etc..?
Just thinking as an alternative as a collegue who used callback extensively said" dont use callback use 2 services".
What would you do if you had to process 2000 invoices and notify the user for each one
Any suggestions?
On one project we have done the following:
All windows clients also host a WCF service
When the windows client starts it registers itself with the server, that this user is loggon with this IP address.
The server stores info on who is logged in where
Then we can send a message to the user whenever we want
When the client recieves the message we fire an event, then whatever part of the UI that is affected can update itself or show a message.
I have a vb.net 2.0 winforms project that is full of all kinds of business reports (generated with Excel interop calls) that can be run "on-demand". Some of these reports filter through lots of data and take a long time to run - especially on our older machines around the office.
I'd like to have a system where a report request can be made from the client machines, some listener sees it, locates a server with low-load, runs the report on that server, and emails the result to the user that requested it.
How can I design such a change? All our reports take different parameters, and I can't seem to figure out how to deal with this. Does each generator need to inherit from a "RemoteReport" class that does this work? Do I need to use a service on one of our servers to listen for these requests?
One approach you could take is to create a database that the clients can connect to, and have the client add a record that represents a report request, including the necessary parameters which could be passed in an xml field.
You can then have a service that periodically checks this database for new requests, and depending on how many other requests are current processing, submit the request to the least busy server.
The server would then be able to run the report and email the file to the user.
This is by no means a quick solution and will likely take some time to design the various elements and get them to work together, but its not impossible, especially considering that it has the possibility to scale rather well (adding more available/more powerful servers).
I developed a similar system where a user can submit a request for data from a web interface, that would get picked up by a request manager service that would delegate the request to the appropriate server based on the type of request, while providing progress indication to the client.
How about write a web service that accepts reporting requests. On completion the reports could be emailed to the users. The web service can provide a Status method that allows your WinForms app to interrogate the current status of the report requests.