Allow property bindings to be easily created from JavaScript

Properties can now be assigned a function that returns the binding
value.

Task-number: QTBUG-14964
Reviewed-by: Aaron Kennedy

1 files changed, 10 insertions, 32 deletions

diff --git a/doc/src/declarative/javascriptblocks.qdoc b/doc/src/declarative/javascriptblocks.qdoc
index d221205..65877f9 100644
--- a/doc/src/declarative/javascriptblocks.qdoc
+++ b/doc/src/declarative/javascriptblocks.qdoc
@@ -200,37 +200,12 @@ Likewise, the \l {Component::onDestruction} attached property is triggered on
 component destruction.
 
 
-\section1 Property Assignment vs Property Binding
+\section1 JavaScript and Property Binding
 
-When working with both QML and JavaScript, it is important to differentiate between
-QML \l {Property Binding} and JavaScript value assignment. In QML, a property 
-binding is created using the \e {property: value} syntax:
+Property bindings can be created in JavaScript by assigning the property with a \c function
+that returns the required value.
 
-\code
-Rectangle {
-    width: otherItem.width
-}
-\endcode
-
-The \c width of the above \l Rectangle is updated whenever \c otherItem.width changes. On the other
-hand, take the following JavaScript code snippet, that runs when the \l Rectangle is created:
-
-\code
-Rectangle {
-
-    Component.onCompleted: {
-        width = otherItem.width;
-    }
-}
-\endcode
-
-The \c width of this \l Rectangle is \e assigned the value of \c otherItem.width using the
-\e {property = value} syntax in JavaScript. Unlike the QML \e {property: value} syntax, this
-does not invoke QML property binding; the \c rectangle.width property is set to the value
-of \c otherItem.width at the time of the assignment and will not be updated if that value
-changes.
-
-See \l {Property Binding} for more information.
+See \l {Binding Properties from JavaScript} for details.
 
 
 \section1 Receiving QML Signals in JavaScript
@@ -315,10 +290,13 @@ This restriction exists as the QML environment is not yet fully established.
 To run code after the environment setup has completed, refer to
 \l {Running JavaScript at Startup}.
 
-\o The value of \c this is currently undefined in QML
+\o The value of \c this is currently undefined in QML in the majority of contexts
+
+The \c this keyword is supported when \l {Binding Properties from JavaScript}
+{binding properties from JavaScript}. In all other situations, the value of
+\c this is undefined in QML.
 
-The value of \c this is undefined in QML.  To refer to any element, provide
-an \c id.  For example:
+To refer to any element, provide an \c id.  For example:
 
 \qml
 Item {