I am using Sweet Alert for a popup on my product view in an E-commerce Application with two buttons: one for going on cart View and another for reloading the vi
Use backdrop:true with the allowOutsideClick: false as following below. It worked for me.
swal({
    backdrop:true,
    allowOutsideClick: false,
    title:'Warning!',
    text:'Do you want to delete records?',
    type:'warning',
    showCancelButton: 0,
    confirmButtonText: 'OK',
}).then(function(e) {
    if (e.value) {
        //do what you want
    }
})
swal(
         "Records will be deleted permanently.",  //title
         "Do you want to delete records?",  //text
         "warning",  //icon
         {
              closeOnClickOutside: false, // prevent close on click anywhere/outside
              buttons: ["No", "Yes"], //with custom label
              dangerMode: true,
         }
    ).then(ok => {
         if (ok) {
              console.log("deleted")
         }
         else {
              console.log("not deleted")
         }
    })
You can set this property:
allowOutsideClick: true
If the answers above do not work for you try:
closeOnClickOutside: false
For latest version it is
allowOutsideClick: false
For SweetAlert 2:
allowOutsideClick: false
and version 3 and some below version 2:
closeOnClickOutside: false