MDL-59936 javascript: hide modal footer without content

lib/amd/src/modal.js

@@ -358,7 +358,8 @@ define(['jquery', 'core/templates', 'core/notification', 'core/key_codes',
     };
 
     /**
-     * Set the modal footer element.
+     * Set the modal footer element. The footer element is made visible, if it
+     * isn't already.
      *
      * This method is overloaded to take either a string
      * value for the body or a jQuery promise that is resolved with HTML and Javascript
@@ -368,6 +369,9 @@ define(['jquery', 'core/templates', 'core/notification', 'core/key_codes',
      * @param {(string|object)} value The footer string or jQuery promise
      */
     Modal.prototype.setFooter = function(value) {
+        // Make sure the footer is visible.
+        this.showFooter();
+
         var footer = this.getFooter();
 
         if (typeof value === 'string') {
@@ -396,6 +400,34 @@ define(['jquery', 'core/templates', 'core/notification', 'core/key_codes',
         }
     };
 
+    /**
+     * Check if the footer has any content in it.
+     *
+     * @method hasFooterContent
+     * @return {bool}
+     */
+    Modal.prototype.hasFooterContent = function() {
+        return this.getFooter().children().length ? true : false;
+    };
+
+    /**
+     * Hide the footer element.
+     *
+     * @method hideFooter
+     */
+    Modal.prototype.hideFooter = function() {
+        this.getFooter().addClass('hidden');
+    };
+
+    /**
+     * Show the footer element.
+     *
+     * @method showFooter
+     */
+    Modal.prototype.showFooter = function() {
+        this.getFooter().removeClass('hidden');
+    };
+
     /**
      * Mark the modal as a large modal.
      *
@@ -508,6 +540,12 @@ define(['jquery', 'core/templates', 'core/notification', 'core/key_codes',
             return;
         }
 
+        if (this.hasFooterContent()) {
+            this.showFooter();
+        } else {
+            this.hideFooter();
+        }
+
         if (!this.isAttached) {
             this.attachToDOM();
         }