Implementation of checkbox groups.

The 'checked'/'attr'-data-query with 'checked' as attribute will accept
arrays/array-observables as the 'value' parameter
and try to find their value in the array to set the value
and add their value to the array when checked.

src/query/DomQuery.js

@@ -359,7 +359,16 @@ define([
       var tagName = element.tagName.toLowerCase();
       var type = element.getAttribute('type');
 
-      if (type == 'checkbox') {
+      if (blocks.isArray(value()) && (type == 'checkbox' || type == 'radio')) {
+        var unwrapedValue = value();
+        if (element.checked) {
+          if (unwrapedValue.indexOf(element.value) == -1) {
+            value.add(element.value);
+          }
+        } else if (unwrapedValue.indexOf(element.value) !== -1) {
+          value.splice(unwrapedValue.indexOf(element.value), 1);
+        }
+      } else if (type == 'checkbox') {
         value(element.checked);
       } else if (tagName == 'select' && element.getAttribute('multiple') !== null) {
         var values = [];

src/query/VirtualElement.js

@@ -150,11 +150,15 @@ define([
         if (attributeName == 'checked' && attributeValue != null && !this._fake) {
           if (this._attributes.type == 'radio' &&
             typeof attributeValue == 'string' &&
-            value != attributeValue && value != null) {
+            value != attributeValue && value != null && !blocks.isArray(attributeValue)) {
 
             attributeValue = null;
           } else {
-            attributeValue = attributeValue ? 'checked' : null;
+            if (blocks.isArray(attributeValue)) {
+              attributeValue = attributeValue.indexOf(value) !== -1 ? 'checked' : null;
+            } else {
+               attributeValue = attributeValue ? 'checked' : null;
+            }
           }
         } else if (attributeName == 'disabled') {
           attributeValue = attributeValue ? 'disabled' : null;

src/query/dom.js

@@ -141,7 +141,11 @@ define([
 
           attributeValue = false;
         } else {
-          attributeValue = !!attributeValue;
+          if (blocks.isArray(attributeValue)) {
+            attributeValue = attributeValue.indexOf(element.value) !== -1;
+          } else {
+            attributeValue = !!attributeValue;
+          }
         }
       }