How to save/edit object and refresh datagrid using request factory - gwt

Question

I started with dynatableref example of Request Factory. I read request factory document. but still I am unclear about life cycle or flow of client to server.
I want to make a call to server. Insert data and update grid also. It is easy with RPC call. But I don't understand how to do with Request Factory.
This is one method of request factory. It call persist method automatically of server. It refresh grid also automatically. can I anybody tell how is it working?
context.fire(new Receiver<Void>() {
#Override
public void onConstraintViolation(Set<ConstraintViolation<?>> errors) {
// Otherwise, show ConstraintViolations in the UI
dialog.setText("Errors detected on the server");
editorDriver.setConstraintViolations(errors);
}
#Override
public void onSuccess(Void response) {
// If everything went as planned, just dismiss the dialog box
dialog.hide();
}
});
I want to edit some data in to grid also. is this method help me? or I have to write other method.
I wrote other method like
requestFactory.schoolCalendarRequest().savePerson(personProxy).fire(new Receiver<PersonProxy>() {
#Override
public void onSuccess(PersonProxy person) {
// Re-check offset in case of changes while waiting for data
dialog.hide();
}
});
This is not refreshing grid. why?

Answer 1

The flow client-server of the RuequestFactory is similar to RPC or any XMLHTTP request
1) You invoke a remote method on the server.
2) You receive a response in the Receiver object (which is the Callback object). In onSeccess Method you get the returned object if everything went well. onFailure you get an error if something went wrong.
So to populate the Person table from data retrieved from the server the code should look something like this
requestFactory.schoolCalendarRequest().getPersonList(param1).fire(new Receiver<List<PersonProxy>>() {
#Override
public void onSuccess(List<PersonProxy> personList) {
personTable.getDataProvider().setList(personList);
}
});
Now when you edit a Person (e.g. name ) it's important to initialize and use the same RequestContext until you call fire on the request. So the part where you update the Person's name should look something like this
column.setFieldUpdater(new FieldUpdater<Person, String>() {
#Override
public void update(PersonProxy personProxy, String value) {
RequestContext requestContext = requestFactory.schoolCalendarRequest()
PersonProxy personProxy= requestContext.edit(personProxy);
personProxy.setName(value);
requestFactory.schoolCalendarRequest().savePerson(personProxy).fire(new Receiver<PersonProxy>() {
#Override
public void onSuccess(PersonProxy person) {
//Do something after the update
}
});
}
});
The interaction with the RequestFactory should be placed in a Presenter, so you should probably consider implementing a MVP pattern.