bootstrap 4 close modal outside code example
Example 1: prevent bootstrap modal from closing when clicking outside
<div id="idModal" class="modal hide" data-backdrop="static" data-keyboard="false">
Example 2: bootstrap modal popup backdrop false
<button class='btn btn-danger fa fa-trash' data-toggle='modal' data-target='#deleteModal' data-backdrop='static' data-keyboard='false'></button>