Merge pull request #297 from paulmsmith/feature/anchor-buttons

Feature/anchor buttons

javascripts/govuk/anchor-buttons.js

@@ -0,0 +1,61 @@
+// javascript 'shim' to trigger the click event of element(s) 
+// when the space key is pressed.
+// 
+// usage instructions:
+// GOVUK.anchorButtons.init();
+// 
+// If you want to customise the shim you can pass in a custom configuration
+// object with your own selector for the target elements and addional keyup 
+// codes if there becomes a need to do so. For example:
+// GOVUK.anchorButtons.init({ selector: '[role="button"]' }); 
+(function(global) {
+  "use strict"; 
+
+  var $ = global.jQuery;
+  var GOVUK = global.GOVUK || {};  
+
+  GOVUK.anchorButtons = {
+
+    // default configuration that can be overridden by passing object as second parameter to module
+    config: {
+      // the target element(s) to attach the shim event to
+      selector: 'a[role="button"]',
+      // array of keys to match against upon the keyup event
+      keycodes: [
+        32 // spacekey
+      ],
+    },
+
+    // event behaviour (not a typical anonymous function for resuse if needed)
+    triggerClickOnTarget: function triggerClickOnTarget(event) {
+      var code = event.charCode || event.keyCode; 
+      // if the keyCode/charCode from this event is in the keycodes array then 
+      if ($.inArray(code, this.config.keycodes) !== -1) {
+        event.preventDefault();
+        // trigger the target's click event
+        $(event.target).trigger("click");
+      }
+    },
+
+    // By default this will find all anchors with role attribute set to 
+    // 'button' and will trigger their click event when the spaceky (32) is pressed.
+    // @method init
+    // @param  {Object}   customConfig                object to override default configuration
+    //         {String}   customConfig.selector       a selector for the elements to be 'clicked'
+    //         {Array}    customConfig.keycodes       an array of javascript keycode values to match against that when pressed will trigger the click
+    init: function init(customConfig) { 
+      // extend the default config with any custom attributes passed in
+      this.config = $.extend(this.config, customConfig);
+      // if we have found elements then:
+      if($(this.config.selector).length > 0) {
+        // listen to 'document' for keyup event on the elements and fire the triggerClickOnTarget
+        $(document).on('keyup', this.config.selector, this.triggerClickOnTarget.bind(this));
+      }    
+    }
+
+  };
+
+  // hand back to global
+  global.GOVUK = GOVUK;
+
+})(window);