User starts up a silverlight application in their browser by navigating to a given URL.
User then opens another browser and starts up the same silverlight application by navigating to the same URL.
Can the second instance of the application detect that there is already an instance running on the same computer?
Can it detect itself if both applications are running within the same browser instance?
I would expect the answer to be 'no' but thought that i would ask it anyway. Otherwise i believe that i will have to setup a webservice and have each instance register itself and send requests to other instances from the same IP. does that sound reasonable?
I think you may be looking for LocalMessageSender and LocalMessageReceiver. I believe these are new classes in Silverlight 3 allowing two Silverlight applications running on the same local computer to communicate.
More detail: Communication Between Local Silverlight-Based Applications (msdn)
This will work, I've done it myself. This code from the Microsoft site demonstrates how you set up a LocalMessage 'receiver". If it throws an error, it is because another instance of the Silverlight app is already running.
public Receiver()
{
InitializeComponent();
LocalMessageReceiver messageReceiver =
new LocalMessageReceiver("receiver",
ReceiverNameScope.Global, LocalMessageReceiver.AnyDomain);
messageReceiver.MessageReceived += messageReceiver_MessageReceived;
try
{
messageReceiver.Listen();
}
catch (ListenFailedException)
{
output.Text = "Cannot receive messages." + Environment.NewLine +
"There is already a receiver with the name 'receiver'.";
}
}
I think you're right you can't do it cross-application, but you can do it within a single browser instance using cookies or Isolated Storage.
Related
I have a service that is is self hosted in a WPF application. Also I have a WPF client and a xamarin android client that use the WCF client to consume the service.
I have realize that I can call with no problems from the WPF client, but from android client I only can call 2 times, later the application stop responding and after a time, I get a timeout exception.
I have read threads that say that I have to close the client proxy to solve the problem, because the number of connections are limited in the server, but this doesn't solve the problem. In fact, I have tried to no close the proxy in the WPF application and I don't have problems and I have tried to close the proxy in the android application, in the finally try/catch and in a using block, in both cases the application stops responding.
I try the solutions in threads like this and this, but they doesn't solve my problem.
The code is the following:
WPF client:
int _numeroLlamadas = 0;
GestorAplicacionesServiceProxy _proxy = new GestorAplicacionesServiceProxy();
private void BtnTest_Click(object sender, RoutedEventArgs e)
{
txtResultado.Text = _proxy.GetData(2);
_numeroLlamadas = _numeroLlamadas + 1;
txtNumeroLlamadas.Text = _numeroLlamadas.ToString();
}
In this case I have a counter to know how many times I can call to the service, and I don't have problems to call 20, 30, 40... times.
In the android application I have this code in the click event of a button:
using (GestorAplicacionesServiceProxy miProxy = new GestorAplicacionesServiceProxy(_binding, _endPointAddress))
{
string miResultado = miProxy.GetData(2);
Toast.MakeText(this, "Hola", ToastLength.Short).Show();
}
In this case I use a using block to dispose the proxy when I finish to use it. But I only can call 2 times and in the next call, the application throw a timeout exception.
The service, the instance context mode is per call.
How the WPF client works fine and the android application isn't, I was thinking that perhaps it is because the android application has different considerations.
Thanks.
I am developing a Line-of-Business app for a client. The client specified the devices that were supposed to be used (some Dell tablet with Windows 8.1). Now, that the development is almost done and we were ready to release the first phase of the application, the client informed us that they have changed their mind and all those Dell tablets will run windows 10. I upgraded one tablet that I used for development and testing to Windows 10 as well. The tablet uses a RESTful Web API to access data stored in a repository. Obviously, the URL of the Web API must be configured in the settings of the app before the app can retrieve any data from the repository.
So I create the App Package to sideload the app on the tablet. The installation works properly, the app starts well for the first time. I go into the settings, set the URL and close the app.
When I try to restart, the app gets stuck showing the Splash Screen. If I try to access the Settings, I am informed that the settings for my app are not available at that time. The only way to get out of this is to uninstall the app and reinstall it again.
This is the code I use to save and retrieve the settings:
public void SaveSetting<T>(string settingName, T value)
{
ApplicationData.Current.LocalSettings.Values[settingName] = value;
}
public T GetSetting<T>(string settingName)
{
var localSettings = ApplicationData.Current.LocalSettings.Values;
if (localSettings.ContainsKey(settingName))
{
var value = localSettings[settingName];
if (value is T)
{
return (T)value;
}
}
// else, in all other cases
return default(T);
}
An interesting thing I noticed is that sometimes, depending on what I try to save in the settings, the app starts. For example, I was playing with it and tried to save some garbage instead of the correct URL. So instead of "http://x.x.x.x:nnnnn" I saved "a". The app started correctly, I got past the splash screen but obviously, I couldn't get any data.
Any ideas as to what exactly is happening? Did the access method for local settings change in Windows 10?
I have been scratching my head over this for the past couple of days. Initially, I thought it is a matter of permissions to create the Local Settings file, so I dedicated a lot of energy trying to find a solution from that perspective. However, as I said, if I dump some garbage in the settings, it works, so it's not a matter of permissions. Could it be that and IP address like "x.x.x.x" needs to be saved in a different way than as a string?
Any advice would be highly appreciated.
TIA,
Eddie
After I added some logging to my application I was able to prove that the app had no issues reading the settings. It's what it tried to do with them that it did not work. The URL read from the settings was correct but when the app tried to make calls to the Web API, the calls threw an exception and the app stopped working. So this shouldn't have been a question in the first place.
Thanks, Eddie
I'm attempting to consume a SOAP service in a Silverlight 5 application and I'm completely lost. This is my first Silverlight app and only my second time using web services in a .NET application.
In a separate .NET application, the only way I was able to get it to work was by adding the WSDL as a Web Reference; the application would not build when I added it as a Service Reference. In talking to the WSDL provider, I discovered that the WSDL was compiled using the .NET 2.0 framework...hence the need to add it as a Web Reference.
From the research I've done thus far, I see that Silverlight doesn't support adding a Web Reference. So I tried adding it to the hosting ASP.NET application as a Web Reference then started the server.
Back in my Silverlight app, I selected the option to add a Service Reference and pointed to the WSDL file now at http://localhost:55265/Web%20References/THINKWebService/SLWebSvc_734_Upgrade.wsdl. Visual Studio seemed to pick it up just fine and generate the proxies.
Here's where I start to get stuck. If my research is correct, a WCF reference was created and should be used in that manner. I've never used WCF so I did some reading on how to send/receive requests and this is the best code I've come up with, based on examples in the MSDN library (I inserted it into a button click event so I would know exactly when the code was executing):
private void Button1Click(object sender, RoutedEventArgs e)
{
var client = new ThinkSoapClient();
var userLoginData = new user_login_data {login = "foo", password = "bar"};
var customerIdentifier = new customer_identifier {customer_id = 6677070};
// the debugger halts on this next line and
// references the "dsn"...it's the 4th argument
client.CustomerLoginInfoSelectAsync(userLoginData, customerIdentifier, "", "myDSN");
// I'm not sure if this next line is even needed
client.CustomerLoginInfoSelectCompleted += CustomerLoginInfoSelectCallback;
MessageBox.Show(string.Format("CustomerLoginInfoSelectAsync({0},{1})", userLoginData, customerIdentifier));
}
// here's the callback method
static void CustomerLoginInfoSelectCallback(object sender, CustomerLoginInfoSelectCompletedEventArgs e)
{
MessageBox.Show(string.Format("CustomerLoginInfoSelect Result: {0}", e.Result));
}
As I mentioned in the code above, the debugger halts when executing the client.CustomerLoginInfoSelectAsync method. Here's the error message: XmlSerializer attribute System.Xml.Serialization.XmlAttributeAttribute is not valid in dsn. Only XmlElement, XmlArray, XmlArrayItem and XmlAnyElement attributes are supported when IsWrapped is true.
From the research I've done, I think this error is being caused because the the SOAP action element contains an attribute dsn (not sure, though, if I would be getting this error if the sub-elements also had attributes).
I did a find/replace for IsWrapped=true to IsWrapped=false in Reference.cs but I got the same error but the last word was false instead of true.
I'm not sure if I'm making any sense as to what I'm after, so here's what the generated XML should look like in case it helps:
...
<customer_login_info_select_request dsn="myDSN">
<user_login_data>
<login>foo</login>
<password>bar</password>
</user_login_data>
<customer_identifier>
<customer_id>6677070</customer_id>
</customer_identifier>
<login/> <!--corresponds to the empty string in the call to CustomerLoginInfoSelectAsync-->
</customer_login_info_select_request>
...
So at this point, I'm completely lost. Any insights would be greatly appreciated. If there's any other info I can provide, please let me know.
While possible the normal solution would be to assume it is "just another data source" and use the Web reference on your Server side instead to provide data (and to provide insulation against future changes).
Silverlight App <=> Silverlight Web Services <= External/Legacy Web Service
Keep your Silverlight app slim and let the server do any heavy lifting for you.
How to make sure that only one instance of a silver light web out of browser application is running?
How to make sure that only one instance of a silverlight web application inside the web browser is running?
Take a look at the part of the Silverlight Docs: Implement Communication Between Local Silverlight-Based Applications
You can use the LocalMessageSender and LocalMessageReceiver. Create a sender and send a message, if you get a response inform the user by loading an alternate root visual. If you don't get a response set up a receiver so that any other sender do gets a response.
I have a silverlight business aplication that gets data from silverlight enabled webservice.
When I run the application in dev environment, it works fine.
when i deploy the application and the Asp.net web development server is working, then to the application works fine.
But when I stop the development server, the application can't access a service.
My questions are:
When I deploy a silverlight business application, doesn't the service get deployed and get started.
The endpoint address in my ServiceReferences.Clientconfig file is endpoint address="http://localhost:9702/MyWebservice.scv. Do I need to change this?
The enpoint address in the web.config is blank.
Appreciate your help
Because the WCF client code is declared as a "partial" class, what I've been doing to this point is creating another c# partial class file to host a GetClient() method on it. You'll notice that the code is taking into account the port that the service is on... in a few of the environments that I've posted or will be posting to, as well as the development environment, the application is not always on port 80.
Namespace Project.Service
{
public partial class ServiceClient
{
public static ServiceClient GetClient()
{
return new ServiceClient("CustomBinding_Service",
new System.ServiceModel.EndpointAddress(new Uri(string.Format("{0}://{1}:{2}/Services/Service.svc",
Application.Current.Host.Source.Scheme, Application.Current.Host.Source.Host, Application.Current.Host.Source.Port), UriKind.Absolute)));
}
}
}
Hope this helps someone!
Yes you are going to want to change your endpoint address. I recommend doing it in the silverlight code when creating the connection to the WCF service. The service itself lives on the web server, whereas the silverlight application lives on the clients computer. If the web server stops, the web service stops but the silverlight app can keep running.
edit:
To do this in code, as long as the path is always in the same domain as the app you can use do like so:
BasicHttpBinding binding = new BasicHttpBinding(BasicHttpSecurityMode.None) //Use whatever security you need here
{
MaxReceivedMessageSize = int.MaxValue,
MaxBufferSize = int.MaxValue
};
Client client = new Client(binding, new EndpointAddress(new Uri(Application.Current.Host.Source, "../MyService.svc")));
Thanks so much for your help. I tried your approach to create the client code but that didn't work. And that's because the problem seems to be somewhere else.
So I installed fiddler to see the traffic.
Fiddler showed that the service was being accessed but the http response code was 302 showing that there was some redirection involved.
The address of my application is like this http:///Silverlightapp/(S(oirppxrwzhlf2a2vbia1ui45))/Default.aspx#/Home and it is hosted on IIS 6.
So I had to employ a workaround by installing the service on machine with IIS7 (and there was no session id involved like in the above url).I still kept the silverlight application hosted on IIS 6.
Anyway, in summary, to anyone who reads the thread, I did the following to troubleshoot and solve issue(temporarily)
Changed the end point address in the ServiceReferences.ClientConfig file. When you add the service using discover option in VS, the endpoint address is of the localhost and this must be changed.
Registered the service model using ServiceModelReg -i command. (this solved my problem that my applicaiton was only working from development server and not IIS)
-Put the CrossDomain and ClientAccessPolicy files in c:]inetpub\wwwroot folders.
-Used fiddler to look at http response codes. I had to do no configuration in fiddler.
Changed the binarymessageEncoding to textMessageEncoding iin the web.config file of the silverlight web project that also hosted the ecf service. I did this becasue adding a silverlight enabled wcf service creates a custom binding configuration in the web.config file by default uses binary encoding. I needed text encoding to see errors in fidder. But this didn't help much becasue I only saw the name of the operation in the Inspector>xml tab in fiddler. This was the same even after my issues was resolved by workaround.
Thanks for the help
Don't do it in code. Otherwise you won't be able to change it later without recompiling the application (when the address will need to change, perhaps years down the road when you've lost the source code :)
Change the address in ServiceReferences.ClientConfig to where the service is actually hosted... e.g. http://example.com/myVdir/MyWebservice.svc
If later on you need to change the address without recompiling:
- Open the .xap file (it's just a zip file with a different extension)
- Find the .ClientConfig file and change the address
- Put it back together as a .zip file and rename to .xap
Also, I can't remember anymore whether the .ClientConfig supports relative addresses (e.g. just "MyWebService.svc"), but if it does it may be a good solution as well.