Firstly I´d like to apologize for my English if it is not correct. 

I have a problem passing variable from jQuery POST method to my PHP file. I am coding in Apache Cordova for Android. I have this function in JS file: 

2. //.....deletes clicked invitation .......... //
3. function invitation_delete() {
4.     $(document.body).on( 'tap', '.events_pinned_invitations_button_delete', function () {
5.         console.log("ok");
6.         var invitation_id = ($(this)).data("invitation_id");
7.         console.log(invitation_id);
8.         $.post('http://10.0.0.2/habitoo15/mobile/invitations_delete.php' , {invitation_id: invitation_id}, function(data) {
9.             console.log(data);
10.         });
11.     });

and this is php file: 

2. $invitation_id = $_POST['invitation_id'];
3. echo $invitation_id;

If I click the button, console will output: 

"ok"     ...       ( expected )

"1"       ...     ( expected - right number )

" "        ...     ( unexpected, seems like variable got lost on the way and it takes like 5 seconds before console outputs last line )

If I use GET method insted of POST ( in both files ), console will output:

as I would expect. Also I need to pass 2 variables ( second one being string ). If I try that, then the "1" passes ok but the string is cutted in the middle and console outputs just first part of it. 

Thanks for any help or explanation. 

Tomas