Extjs how to memorize a response from an Ajax request? - ajax

Question

I want to memorize the response of an ajax request, how I can do it?
In the code above, I found "" in the console...
How can I do it? any suggests?
var jsoncolumnset = '';
Ext.Ajax.request({
scope: this,
url: 'index.php',
params: {
m: 'Columnset',
a: 'readDefault'
},
reader: {
type: 'json',
root: 'rows'
},
success: function(response){
//Passo tutto il json (dovrebbe essere fatto un decode, ma viene gestito da Alfresco)
jsoncolumnset = response.responseText;
this.getStore('Documents').proxy.extraParams.columnset = response.responseText;
},
failure: function(){
//TODO: gestione fallimento chiamata
}
});
console.log(jsoncolumnset);

Answer 1

Ajax is asynchronous so while you have started the request in your Ext.Ajax.request call, the response has not come back by the time console.log(jsoncolumnset) is being executed.
The 'success' method will execute when the server response comes back to the browser which could be milliseconds or seconds later - either way the code mapped to the 'success' event is executed after the console.log executes.
So it appears the snippet is from code nested in some object since you have the "this" scope in place. .
You can add some event based logic that works nicely with ajax. Here is an idea:
// add this custom event in line with other bindings or in the objects constructor or a controllers init method
this.on('columnsready', this.logColumns);
// add this method to the main object
handleColumnResponse: function () {
//Passo tutto il json (dovrebbe essere fatto un decode, ma viene gestito da Alfresco)
this.jsoncolumnset = response.responseText;
this.getStore('Documents').proxy.extraParams.columnset = response.responseText;
// fire the custom event
this.fireEvent('columnsready');
},
// add this as an example of where you would put more logic to do stuff after columns are setup
logColumns: function () {
console.log(this.jsoncolumnset);
},
Ext.Ajax.request({
scope: this,
url: 'index.php',
params: {
m: 'Columnset',
a: 'readDefault'
},
reader: {
type: 'json',
root: 'rows'
},
// map to the handler method in the main object
success: this.handleColumnResponse,
failure: function(){
//TODO: gestione fallimento chiamata
}
});