feat(autocomplete): option to toggle the clear button

*  Adds a new attribute, which allows developers to explicitly show the clear button for all types of autocomplete's.

Closes #2727

Author: devversion

src/components/autocomplete/autocomplete.scss

@@ -1,5 +1,7 @@
 // The default item height is also specified in the JavaScript.
 $md-autocomplete-item-height: 48px !default;
+$md-autocomplete-clear-size: 30px !default;
+$md-autocomplete-input-offset: 20px !default;
 
 @keyframes md-autocomplete-list-out {
   0% {
@@ -55,14 +57,24 @@ md-autocomplete {
     md-autocomplete-wrap {
       height: auto;
     }
-    button {
-      position: absolute;
-      top: auto;
-      bottom: 0;
-      right: 0;
-      width: 30px;
-      height: 30px;
+
+    .md-show-clear-button {
+
+      button {
+        display: block;
+        position: absolute;
+        right: 0;
+        top: $md-autocomplete-input-offset;
+        width: $md-autocomplete-clear-size;
+        height: $md-autocomplete-clear-size;
+      }
+
+      input {
+        // Add padding to the end of the input to avoid overlapping with the clear button.
+        @include rtl-prop(padding-right, padding-left, $md-autocomplete-clear-size, 0);
+      }
     }
+
   }
   md-autocomplete-wrap {
 
@@ -130,12 +142,12 @@ md-autocomplete {
     line-height: 40px;
     height: 40px;
   }
-  button {
+  .md-show-clear-button button {
     position: relative;
     line-height: 20px;
     text-align: center;
-    width: 30px;
-    height: 30px;
+    width: $md-autocomplete-clear-size;
+    height: $md-autocomplete-clear-size;
     cursor: pointer;
     border: none;
     border-radius: 50%;

src/components/autocomplete/autocomplete.spec.js

@@ -1337,6 +1337,80 @@ describe('<md-autocomplete>', function() {
 
   });
 
+  describe('clear button', function() {
+
+    it('should show the clear button for inset autocomplete', function() {
+      var scope = createScope();
+
+      var template =
+        '<md-autocomplete ' +
+            'md-selected-item="selectedItem" ' +
+            'md-search-text="searchText" ' +
+            'md-items="item in match(searchText)" ' +
+            'md-item-text="item.display" ' +
+            'placeholder="placeholder"> ' +
+          '<span md-highlight-text="searchText">{{item.display}}</span>' +
+        '</md-autocomplete>';
+
+      var element = compile(template, scope);
+      var ctrl = element.controller('mdAutocomplete');
+      var wrapEl = element.find('md-autocomplete-wrap');
+
+      expect(ctrl.scope.clearButton).toBe(true);
+      expect(wrapEl).toHaveClass('md-show-clear-button');
+    });
+
+    it('should not show the clear button for floating label autocomplete', function() {
+      var scope = createScope();
+
+      var template =
+        '<md-autocomplete ' +
+            'md-selected-item="selectedItem" ' +
+            'md-search-text="searchText" ' +
+            'md-items="item in match(searchText)" ' +
+            'md-item-text="item.display" ' +
+            'md-floating-label="Label"> ' +
+          '<span md-highlight-text="searchText">{{item.display}}</span>' +
+        '</md-autocomplete>';
+
+      var element = compile(template, scope);
+      var ctrl = element.controller('mdAutocomplete');
+      var wrapEl = element.find('md-autocomplete-wrap');
+
+      expect(ctrl.scope.clearButton).toBe(false);
+      expect(wrapEl).not.toHaveClass('md-show-clear-button');
+    });
+
+    it('should allow developers to toggle the clear button', function() {
+
+      var scope = createScope();
+
+      var template =
+        '<md-autocomplete ' +
+            'md-selected-item="selectedItem" ' +
+            'md-search-text="searchText" ' +
+            'md-items="item in match(searchText)" ' +
+            'md-item-text="item.display" ' +
+            'md-floating-label="Label" ' +
+            'md-clear-button="showButton">' +
+          '<span md-highlight-text="searchText">{{item.display}}</span>' +
+        '</md-autocomplete>';
+
+      var element = compile(template, scope);
+      var ctrl = element.controller('mdAutocomplete');
+      var wrapEl = element.find('md-autocomplete-wrap');
+
+      expect(ctrl.scope.clearButton).toBeFalsy();
+      expect(wrapEl).not.toHaveClass('md-show-clear-button');
+
+      scope.$apply('showButton = true');
+
+      expect(ctrl.scope.clearButton).toBe(true);
+      expect(wrapEl).toHaveClass('md-show-clear-button');
+    });
+
+  });
+
   describe('xss prevention', function() {
 
     it('should not allow html to slip through', inject(function($timeout, $material) {

src/components/autocomplete/js/autocompleteController.js

@@ -73,7 +73,13 @@ function MdAutocompleteCtrl ($scope, $element, $mdUtil, $mdConstant, $mdTheming,
    * Initialize the controller, setup watchers, gather elements
    */
   function init () {
-    $mdUtil.initOptionalProperties($scope, $attrs, { searchText: '', selectedItem: null });
+
+    $mdUtil.initOptionalProperties($scope, $attrs, {
+      searchText: '',
+      selectedItem: null,
+      clearButton: false
+    });
+
     $mdTheming($element);
     configureWatchers();
     $mdUtil.nextTick(function () {

src/components/autocomplete/js/autocompleteDirective.js

@@ -87,6 +87,7 @@ angular
  *     make suggestions
  * @param {number=} md-delay Specifies the amount of time (in milliseconds) to wait before looking
  *     for results
+ * @param {boolean=} md-clear-button Whether the clear button for the autocomplete input should show up or not.
  * @param {boolean=} md-autofocus If true, the autocomplete will be automatically focused when a `$mdDialog`,
  *     `$mdBottomsheet` or `$mdSidenav`, which contains the autocomplete, is opening. <br/><br/>
  *     Also the autocomplete will immediately focus the input element.
@@ -151,6 +152,17 @@ angular
  * In this example, our code utilizes `md-item-template` and `md-not-found` to specify the
  *     different parts that make up our component.
  *
+ * ### Clear button for the input
+ * By default, for floating label autocomplete's the clear button is not showing up
+ * ([See specs](https://material.google.com/components/text-fields.html#text-fields-auto-complete-text-field))
+ *
+ * Nevertheless, developers are able to explicitly toggle the clear button for all types of autocomplete's.
+ *
+ * <hljs lang="html">
+ *   <md-autocomplete ... md-clear-button="true"></md-autocomplete>
+ *   <md-autocomplete ... md-clear-button="false"></md-autocomplete>
+ * </hljs>
+ *
  * ### Example with validation
  * <hljs lang="html">
  * <form name="autocompleteForm">
@@ -232,7 +244,8 @@ function MdAutocomplete ($$mdSvgRegistry) {
       inputId:          '@?mdInputId',
       escapeOptions:    '@?mdEscapeOptions',
       dropdownItems:    '=?mdDropdownItems',
-      dropdownPosition: '@?mdDropdownPosition'
+      dropdownPosition: '@?mdDropdownPosition',
+      clearButton:      '=?mdClearButton'
     },
     compile: function(tElement, tAttrs) {
       var attributes = ['md-select-on-focus', 'md-no-asterisk', 'ng-trim', 'ng-pattern'];
@@ -250,6 +263,11 @@ function MdAutocomplete ($$mdSvgRegistry) {
         // Retrieve the state of using a md-not-found template by using our attribute, which will
         // be added to the element in the template function.
         ctrl.hasNotFound = !!element.attr('md-has-not-found');
+
+        // By default the inset autocomplete should show the clear button when not explicitly overwritten.
+        if (!angular.isDefined(attrs.mdClearButton) && !scope.floatingLabel) {
+          scope.clearButton = true;
+        }
       }
     },
     template:     function (element, attr) {
@@ -269,8 +287,11 @@ function MdAutocomplete ($$mdSvgRegistry) {
 
       return '\
         <md-autocomplete-wrap\
-            ng-class="{ \'md-whiteframe-z1\': !floatingLabel, \'md-menu-showing\': !$mdAutocompleteCtrl.hidden }">\
+            ng-class="{ \'md-whiteframe-z1\': !floatingLabel, \
+                        \'md-menu-showing\': !$mdAutocompleteCtrl.hidden, \
+                        \'md-show-clear-button\': !!clearButton }">\
           ' + getInputElement() + '\
+          ' + getClearButton() + '\
           <md-progress-linear\
               class="' + (attr.mdFloatingLabel ? 'md-inline' : '') + '"\
               ng-if="$mdAutocompleteCtrl.loadingIsVisible()"\
@@ -366,18 +387,21 @@ function MdAutocomplete ($$mdSvgRegistry) {
                 role="combobox"\
                 aria-haspopup="true"\
                 aria-activedescendant=""\
-                aria-expanded="{{!$mdAutocompleteCtrl.hidden}}"/>\
-            <button\
-                type="button"\
-                tabindex="-1"\
-                ng-if="$mdAutocompleteCtrl.scope.searchText && !$mdAutocompleteCtrl.isDisabled"\
-                ng-click="$mdAutocompleteCtrl.clear($event)">\
-              <md-icon md-svg-src="' + $$mdSvgRegistry.mdClose + '"></md-icon>\
-              <span class="md-visually-hidden">Clear</span>\
-            </button>\
-                ';
+                aria-expanded="{{!$mdAutocompleteCtrl.hidden}}"/>';
         }
       }
+
+      function getClearButton() {
+        return '' +
+          '<button ' +
+              'type="button" ' +
+              'aria-label="Clear Input" ' +
+              'tabindex="-1" ' +
+              'ng-if="clearButton && $mdAutocompleteCtrl.scope.searchText && !$mdAutocompleteCtrl.isDisabled" ' +
+              'ng-click="$mdAutocompleteCtrl.clear($event)">' +
+            '<md-icon md-svg-src="' + $$mdSvgRegistry.mdClose + '"></md-icon>' +
+          '</button>';
+        }
     }
   };
 }