Ok, I've found a way to ignore cancel requests from the client. I'm
posting it here in case someone finds it useful. I still would love
someone explaining my previous questions, but at least I'm able to
continue the development.
The general idea is to use a datasource id in the browser, and store a
request id that will increment each time a new Query.send() is done
(or if the user hits the "cancel" buttom). So here it is (please
excuse any syntax/error, this is just an extract of my code with the
lines that explains what I did):
// prototype class for storing google query objects
var GQuery = Class.create({
initialize: function(){
this.gtables = [];
this.gqueries = [];
this.last_request = [];
},
createGoogleTable: function(datasourceID,parent_div) {
// create the Google Visualization Table
this.gtables[datasourceID] = new google.visualization.Table($
(parent_div));
// create the google Query object
this.gqueries[datasourceID] = new google.visualization.Query(
'YOUR_URL_HERE?p_datasource_id='+datasourceID
);
// create an entry to track it's calls (so we can cancel future
calls)
this.last_request[datasourceID] = {
"id": 0,
"waiting": false
}
// run the query!
this.refreshGoogleTable(datasourceID);
},
refreshGoogleTable: function(id) {
var this_request = this.last_request[id].id;
// check for currently running request for the same datasource
if (this.last_request[id].waiting) {
// found one running
alert( 'We are processing a previous request. '+
'Please wait or cancel it before trying
again.'));
return false;
} else {
// set the new run session!
this.last_request[id].id += 1;
this.last_request[id].waiting = true;
}
this.gqueries[id].send( function(response) {
if (this_request < query.last_request[id].id) {
// old datasource was canceled, do nothing.
return false;
}
if (response.isError()) {
alert('Error found: ' + response.getMessage());
} else {
// redraw the table
query.gtables[id].draw(response.getDataTable());
// clean loading flag
query.last_request[id].waiting = false;
};
});
},
cancelGoogleTable: function(id) {
// set a new request id so that the handler ignores the
previous one
run.last_request[id].id += 1;
run.last_request[id].waiting = false;
}
});
// instantiate and use it!
query = new GQuery;
query.create('datasourceid','parent_div_id');
// then just call refresh or cancel methods as you wish in your page
Regards,
Jose.
On Jun 3, 12:14 pm, Jose Luis Canciani <[email protected]>
wrote:
> I'm still trying to make this work. I've ignored the first option
> because I've read in the forums that we should not modify the tqx
> parameters.
> So I'm concentrating in the second option but still having problems. I
> can manually change the query by modifying the Da attribute
> (query_object.Da), but it doesn't help since I cannot receive a custom
> parameter in the response. The response object ignores any custom
> parameters sent in the JSON from the server.
>
> So still trying to control this. I've been testing a bit more with two
> different handlers in each call to send(). But I find out that if I
> sent two queries (query.send()) one after the other, then only the
> first one call the response handler. The second one does nothing (I do
> see the two request did get out of the client with Firebug). Can
> someone explain why this happen?
>
> Thanks,
> Jose.
>
> On Jun 2, 6:37 pm, Jose Luis Canciani <[email protected]> wrote:
>
> > Hello. I'm building a UI that will let a user run a query dynamically
> > and also cancel it if it's taking to long or if he/she wants to run it
> > again with a different filter for example. I'm having troubles to
> > ignore the previous call from the client. I see two possible solutions
> > but I'm not sure how to implement them:
>
> > 1) If I could make reqId to increase with every new call to the send()
> > method of the Query object then I could ignore previous calls in my
> > handler function. But I don't know how to do that: when calling the
> > send method the reqId always stay in "0".
>
> > 2) I can create a new query object and pass a custom reqId in the URL.
> > That would make the trick, but I don't want to have to create a new
> > object every time. Is it possible to change the URL of a query object
> > once it was instantiated?
>
> > Any other approach would be appreciated.
>
> > Thanks!
> > Jose.
>
>
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Google Visualization API" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/google-visualization-api?hl=en
-~----------~----~----~----~------~----~------~--~---
