Doc: add doc to Anchor Layout Example

Task-number: QTBUG-60635
Change-Id: Iec6cae8c3caeac4bfabddae79b6ed2b47c5f2edf
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@qt.io>

examples/widgets/doc/src/graphicsview-anchorlayout.qdoc

@@ -35,4 +35,47 @@
     class.
 
     \image graphicsanchorlayout-example.png
+
+    The basic steps of this example are:
+    \list
+        \li Create a QGraphicsScene
+        \li Create widgets
+        \li Create a QGraphicsAnchorLayout
+        \li Create a QGraphicsWidget
+        \li Add vertical and horizontal anchors between the widgets
+        \li View the scene with a QGraphicsView object
+    \endlist
+
+    \section1 Creating a QGraphicsScene
+
+    \quotefromfile graphicsview/anchorlayout/main.cpp
+    \skipto QGraphicsScene
+    \printuntil setSceneRect
+
+    \section1 Creating Widgets
+
+    \skipto QGraphicsProxyWidget
+    \printuntil *g
+
+    \section1 Creating a Layout
+
+    \skipto QGraphicsAnchorLayout
+    \printuntil l->setSpacing
+
+    \section1 Creating a QGraphicsWidget
+
+    \skipto QGraphicsWidget
+    \printuntil setLayout(l)
+
+    \section1 Adding Anchors
+
+    \skipto vertical
+    \printuntil l->addAnchor(f, Qt::AnchorRight
+
+    \section1 Viewing the Scene with QGraphicsView
+
+    \skipto scene.addItem
+    \printuntil view.show
+
+    \sa {Simple Anchor Layout Example}
 */