why JQuery Mobile not able to check the checkbox?

I put a checkbox on my webpage, but I want to check it, base on the content of the text file. I am using the below code:

    $(document).ready(function(){
        
    
          $.ajax({
        url : "CH1.txt",
        dataType: "text",
        success : function (data) {
            $("CH1.text").html(data);
            
            var jsonData = JSON.parse(data);
            alert(data);
            
            
            if(data=="1"){$("#CH1CheckBox").prob('checked', true);
                else $("#CH1CheckBox").prob('checked', false);
        
            
        }
    });
       });

when I remove the below script that belonged to JQuery mobile, everything is ok.

but when I use the JQM it not works. I already test with the .attr() function as well, but not constructive. please help. thanks in advance