fix maj fonds sélectionnables (#386)

* fix maj fonds sélectionnables

* fix code format

* add empty option value

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Co-authored-by: Mathilde Marchand <mathilde.marchand@sesan.fr>

Author: mathilde-marchand

lib/mv.js

@@ -323,10 +323,23 @@ var mv = (function () {
       $(".bl." + classe + " input").bind("change", function (e) {
         var id = $(this).parent().parent().attr("data-layerid");
         var value = $(e.currentTarget).prop("checked");
+        var select = $("#frm-bl-visible");
+        var currentValue = select.val();
         if (value === true) {
-          $("#frm-bl-visible option[value='" + id + "']").removeAttr("disabled");
+          select.find("option[value='" + id + "']").removeAttr("disabled");
+          if (!currentValue) {
+            select.val(id).trigger("change");
+          }
         } else {
-          $("#frm-bl-visible option[value='" + id + "']").attr("disabled", "disabled");
+          select.find("option[value='" + id + "']").attr("disabled", "disabled");
+          if (id === currentValue) {
+            var first = select.find("option:not(:disabled)").first();
+            if (first.length) {
+              select.val(first.val()).trigger("change");
+            } else {
+              select.val(null).trigger("change");
+            }
+          }
         }
       });
     },