Merge pull request #192 from itsNikolay/select-all_improvement

Performance for select-all.

js/bootstrap-multiselect.js

@@ -238,10 +238,17 @@
 
                 // Toggle all options if the select all option was changed.
                 if (isSelectAllOption) {
-                    $checkboxesNotThis.filter(function() {
-                        return $(this).is(':checked') != checked;
-                    }).trigger('click');
-                }
+                    if (this.$select[0][0].value == this.options.selectAllValue) {
+                        var values = [];
+                        var options = this.$select.children();
+                        for(var i = 0; i < $checkboxesNotThis.length; i++) {
+                            if (options[i].value !== this.options.selectAllValue) {
+                                values.push(options[i].value);
+                            }
+                        }
+                        checked ? this.select(values) : this.deselect(values)
+                    }
+                 }
 
                 if (checked) {
                     $option.prop('selected', true);