I am trying to communicate between parent window and IFrame(IFrame source being on different domain), which is not allowed directly since the Same Origin Policy. The communication is easy via window.postMessage() method of HTML5. So i searched for existing works in this field and i found gwt-rpc-plus library
It includes a class PostMessageFrameTransportRequest. Now, I think that this would work. But I am not getting on how to use this class.
I need some help with this code and if anyone knows about some other method to give same behavior as window.postMessage() please help me out.
Thanks in advance....
You can just use JSNI to call javascript directly
something like:
private native void sendMessage(String message)/*-{
$wnd.postMessage(...., message);
}-*/;
Related
I’m trying to create a backend for a homepage with GWT. I created a Google Web Application in Eclipse without sample code and now I would like to add the service, but the developer Google guide doesn’t help me. I’m not sure, where to add the interface and how it exactly works.
If I understand the google documentation correctly, I have to add a module and an entry point class, is that correct? It would be great if you could give me some tips and help how to create a rpc service.
If you create a new GWT project in the Eclipse "New Project" wizard, with "Generate project sample code" checked, it will include a fully functioning RPC service with a sample method, which you can then adapt or copy according to your needs.
Out of memory, don't have eclipse in front of me.
First do create a test project with generated testcode, you can delete it afterward.
Yes you will have to add a module.
Create in client the two interfaces for the async calls, inherit it on server side.
Hope I understood your question right.
I'm not sure what would help you the most. Google developer guide was enough for me (at least when I started using it on version 1.6) to create RPC services for my GWT application.
General APP
Module: is the .gwt.xml file. Yes, you'll need it. The GWT compiler will find it automagically and try to compile all the GWT code (the <source> element will tell which subpackage contains Java code that will be converted to JS). It will tell also which class implements the EntryPoint interface. The onModuleLoad will be the code executed when javascript runs in the client page.
RPC
Well, you should first try UI things and only then, when you're confident enough, try the server thing. Anyway the scheme is:
interface MyService extends RemoteService {
List<String> doSomething(String sample, int other);
}
#RemoteServiceRelativePath("../path/to/servlet") // see later
intercace MyServiceAsync {
void doSomething(String sample, int other, AsyncCallback<List<String>> callback);
}
These are the interfaces. Later is the async one. That's what you'll use from client side. Always calling and passing an implementation of AsyncCallback which will receive (sometime later, you don't know when) the result.
First interface is the syncrhonous one. That is what you need to implement on server. You must inherit from RemoteServiceServlet class (it is an implementation of servlet that already does all the values handling), and implement your interface. GWT code does the rest (almost).
public class ServiceImpl extends RemoteServiceServlet implements MyService
{
// implement the method normally
}
From client you'll need to create the service proxy:
private static MyServiceAsync MY_SERVICE = GWT.create(MyService.class);
Yes. I know it's weird how GWT knows MyserviceAsync and MyService work together. Don't worry about that. It works :)
Just use the service like this:
MY_SERVICE.doSomething("value", 111, new AsyncCallback<List<String>>() {
// note that this code executes some time in the future when response from server is back
public void onSuccess(List<String> result) {
Window.alert("Server answered with " + result.size() + " elements!");
}
public void onFailure(Throwable t) {
Window.alert("Server failed: " + t.getMessage());
}
}
Path to server
You'll have to configure your app to make that servlet implementation listen to URL indicated in #RemoteServiceRelativePath. That's the way client knows where to make the request, and the server knows which servlet attends that request. I'd suggest using:
../my-service.gwt as relative path (GWT module gets published in <ROOT>/module_name
and
configuring your web app to use the servlet for /my-service.gwt
But it's entirely upon your preferences :)
Anyway I think Google tutorials are the best. So please copy&paste. Try&modify until you get to understand the whole thing.
I'm implementing a web application which will support different views according to different browsers. For example, In mobile browsers, it will show a smaller view to users with less UI elements. But we'd like to use same presenters.
I have a solution on hand - adding browser type detecting logic in ClientModule, e.g:
if (browser == "iphone") {
bindPresenter(HomePresenter.class, HomePresenter.MyView.class, HomeView.class, HomePresenter.MyProxy.class);
} else if (browser == "ipad") {
bindPresenter(HomePresenter.class, HomePresenter.MyView.class, IPadHomeView.class, HomePresenter.MyProxy.class);
} else {
bindPresenter(HomePresenter.class, HomePresenter.MyView.class, IPhoneHomeView.class, HomePresenter.MyProxy.class);
}
I'm wondering if it is possible to use some ways like deferred binding in GWT-platform. (but I'd like to follow GWT-plarform's structure rather than adding deferred binding code in xxx.gwt.xml).
So my questions are:
1) Are there any other ways to implement the feature mentioned above?
2) Which way is the best, and why?
Thanks in advance!
Best regards,
Jiakuan W
There is an example in the gwt samples folder that does something like you are wanting. I use a version of the sample code in my project -except using Gin to handle the clientfactory functionality. The sample is called mobilewebapp. It involves using a formfactor method in your .gwt.xml to determine which system you are on - in this case it breaks it down into desktop, mobile, and tablet. Then later in your gwt.xml it trades out client factories based on the form factor - I trade out gin models instead. Here is a link to the source for mobilwebapp
GWT does not allow you to set custom user agent types. You're limited to their set of gecko, gecko1_7, safari, IE6, IE7, IE8, and opera.
That being said, you can access the user agent directly and set your logic to switch accordingly with Window.Navigator.getUserAgent(), or via a property provider.
See this similar question on how to do mobile browser detection in GWT for MVP.
Check the gwtp google group, its a good source, and someone posted a pdf about his efforts regarding the sake problem in there.
Anyway, if I recall correctly, he holds multiple gin modules for each client with the presenters and views, runs custom js code on loading and than installs the correct module on the the ginClinet class.
I'm developing a multilanguage application, and use routes with translated segments. For multilingual support I created special Multilingual plugin.
To use translated segments I need set translator for Zend_Controller_Router_Route before routes init. So only possible place for this in my plugin is routeStartup method, but there is one problem here - for determine right locale I need to use properties of request (Zend_Controller_Request_Abstract), like module, controller and action names, but they are not defined yet here in routeStartup method. They are already defined, for example, in routeShutdown - but I can't set translator for route there, because it have to be done before routes init.
So what can I do:
can I get request properties somehow in routeStartup
or can I re-setup translator later in routeShutdown
P.S: there is a question with exactly the same problem Zend_Controller_Router_Route: Could not find a translator, but proposed answers is not the option for me, because I can't just retrieve language code from url with Regex, I have much more complicated code to define right language code.
Thanks.
What about putting your code in preDispatch? That's what I personally do when I need to check if the person is logged in. Maybe you can move your code there too?
I was following an example found here on StackOverflow, and everything went well until I need to register my types.
My web application is running on Silverlight 4, with Prism and MVVM.
The example is using "Microsoft.Practices.Unity" (it's a windows form application)
Bootstrapper.cs
protected override void ConfigureContainer()
{
base.ConfigureContainer();
Container.RegisterType<IApplicationMenuRegistry, MenuRegistry>();
Container.RegisterType<IApplicationCommands, ApplicationCommands>();
Container.RegisterType<ShellViewModel, ShellViewModel>(new Microsoft.Practices.Unity.ContainerControlledLifetimeManager());
}
Mine is using: Microsoft.Practices.Unity.Silverlight (web) and throws the following error:
The non-generic method 'Microsoft.Practices.Unity.IUnityContainer.RegisterType(...) cannot be used with type arguments.
And the RegisterType<> constructor is not visible for me. Which alternatives do I have to register my types?
I am using Unity for Silverlight and have not had this issue.
According to this post, http://unity.codeplex.com/workitem/8205, you need to add "using Microsoft.Practices.Unity;" to the file. The generic versions of Resolve are extension methods and you need to pull in the namespace to use them.
Apparently ReSharper may think the using statement is not needed and may remove it.
Hope that helps.
I'm working on a GWT project and I find it very tedious to have to add a function to my servlet, then copy and paste the function signature into my Service interface, then copy and paste it into my ServiceAsync interface and change the return parameter to be a callback. Is there a tool or a setting where I can just add public methods to my class and they can get copied into the other interfaces? Even if its not automatic it would be nice to be able to select specific methods and have them copied automatically.
I'm using eclipse and ideally it would update my interface each time I save implementation since thats when it checks my code and complains that my changes break the interface.
If you add the method to your *Service interface, then Eclipse can auto-generate the method ("Add unimplemented methods...") in your *ServiceImpl servlet, which you can then just fill in. Also, if you've got the Google Eclipse plugin installed, it will underline the new method in your *Service interface and complain that it's not in the *ServiceAsync. It might have a CTRL + 1 option to generate it in that interface as well.
You don't really need a tool. Just factor out the many RPC methods by just one method that takes a Request/Response. all you need to do is create subclasses of Request/Response and you don't need to think about adding new methods in the 2 interfaces.
You can use Google Guice on the server side to map the incomming request to a class handling the call... or you could use a visitor approach to forward the incoming request to the code handling the request (without resorting on a big instanceof construct).
Instantiations WindowBuilder GWT Designer does exactly what you are looking for.
The RemoteService Wizard will create all three files at the same time as well as keep them in sync as you make changes.
http://www.instantiations.com/windowbuilder/gwtdesigner/index.html
FWIW - I am only a user/purchaser of this product. I am not employed or in any other way related to Instantiations.