Hi

< script >

    $ ( document ) .on ( "pagecreate" , "#pageone", function () {

           // Click on the select dropdown and the input text box is there      

           $ ( "#select" ) val ( "optionone" ) .on ( "tap" , function () {

                $ ( "#inputone" ) .show ();

     // Click on “optiontwo” and “optiontwo” is selected and then click again and “inputone” is hidden

            $ ( "#select" ) .val ( "optiontwo" ) .on ( "tap" , function () {

                $ ( "#inputone " ) .hide ();

     });

});

    });