Disable input Textbox in Sweet Alert when use showLoaderOnConfirm
<p>I am using Sweet Alert plugin to create a button and create a popup to delete a something 
I would like to disable textbox when the delete process is running, and i dont know how to do, anyone lead me?</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>jQuery("#vbb_btn_delete_post").on("click", function(e) {
        swal({
            title: "Lý do xóa bài",
            type: "input",
            showCancelButton: true,
            closeOnConfirm: false,
            animation: "slide-from-top",
            inputPlaceholder: "Write something",
            showLoaderOnConfirm: true,
            customClass: "mySwall"
        },      
        function(inputValue){
            if (inputValue === false) return false;
            if (inputValue === "") {
              swal.showInputError("Bạn cần nhập lý do"); return false;   
            } 
            $('.mySwall').find(':text').prop('disabled', true); //it not working ???          
            jQuery.ajax({
                url: "http://staging.webtretho.vn/forum/editpost.php?do=deletepost&amp;p={vb:raw postinfo.postid}",
                type: "POST",
                data: {
                    "dodelete": "1",
                    "deletepost": "delete",
                    "reason": inputValue,
                    "securitytoken": "{vb:raw bbuserinfo.securitytoken}",
                    "p": {vb:raw postinfo.postid},
                    "url": "{vb:raw url}",
                    "do": "deletepost",
                    "posid": {vb:raw postinfo.postid},
                    "forumid": {vb:raw $GLOBALS.forumid}
                },
                dataType: "html",
                success: function () {
                    //console.log(data);
                    swal("Done!","It was succesfully deleted!","success");
                    window.location="http://staging.webtretho.vn/forum/f"+{vb:raw $GLOBALS.forumid};
                }
            });
        //swal("Nice!", "You wrote: " + inputValue, "success");
        })
});</code></pre>
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