Update richtext.md (#372)
Fire event when span is clicked which is in an a-label of a richtext component.
diff --git a/docs/docs/components/richtext.md b/docs/docs/components/richtext.md
index 38f5f0d..704fc4e 100644
--- a/docs/docs/components/richtext.md
+++ b/docs/docs/components/richtext.md
@@ -64,12 +64,16 @@
## Events
* **common events**. Support [common events](../events/common-events.html).
-* **itemclick**. This event will be fired when
- * An `img` in richtext is clicked
- * None of parents is an `a` tag
- * If the second condition is not satisfied, Weex will try to open the hyperlink of `a` tag instead.
- * **pseudo-ref** of img will be passed to the callback function of onitemclick.
+* **itemclick**. Only works on `img` and `span`:
+ * `img` tag:
+ * None of parents is an `a` tag when the `img` tag is clicked.
+ * If the first condition is not satisfied, Weex will try to open the hyperlink of `a` tag instead.
+ * **pseudo-ref** of img will be passed to the callback function of onitemclick.
+ * `span` tag:
+ * The `span` tag is clicked whose parent is an `a` tag.
+ * The href property is 'click://' (This condition is required on iOS and is optional on Android).
+ * The `a` tag has a `pseudo-ref` property whose value will be sent with the itemclick event.
## Example
-[Demo](http://dotwe.org/vue/f748b0cee3991522a66d4376b66a4f2a)
\ No newline at end of file
+[Demo](http://dotwe.org/vue/f748b0cee3991522a66d4376b66a4f2a)
