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1 files changed, 145 insertions, 3 deletions

diff --git a/doc/src/examples/googlesuggest.qdoc b/doc/src/examples/googlesuggest.qdoc
index bec242d..f3693e9 100644
--- a/doc/src/examples/googlesuggest.qdoc
+++ b/doc/src/examples/googlesuggest.qdoc
@@ -43,10 +43,152 @@
     \example network/googlesuggest
     \title Google Suggest Example
 
-    The Google Suggest example shows how to use the network access manager
-    to get the list of suggested search terms from Google.
+    The Google Suggest example demonstrates how to use the QNetworkAccessManager
+    class to obtain a list of suggestions from the Google search engine as the 
+    user types into a QLineEdit.
 
     \image googlesuggest-example.png
 
-    \note The Google Suggest suggestion service is a registered trademark of Google Inc.
+    The application makes use of the \c get function in
+QNetworkAccessManager to post a request and obtain the result of the search
+query sent to the Google search engine. The results returned are listed as
+clickable links appearing below the search box as a drop-down menu.
+
+The widget is built up by a QLineEdit as the search box, and a QTreeView
+used as a popup menu below the search box.
+
+\section1 GSuggestCompletion Class Declaration
+
+This class implements an event filter and a number of functions to display
+the search results and to determent when and how to perform the search.
+
+\snippet examples/network/googlesuggest/googlesuggest.h 1
+
+The class connects to a QLineEdit and uses a QTreeWidget to display the
+results. A QTimer controls the start of the network requests that are
+executed using a QNetworkAccessManager.
+
+\section1 GSuggestCompletion Class Implementation
+
+We start by defining a constant containing the URL to be used in the Google
+queries. This is the basis for the query. The letters typed into the search
+box will be added to the query to perform the search itself.
+
+\snippet examples/network/googlesuggest/googlesuggest.cpp 1
+
+In the constructor, we set the parent of this GSuggestCompletion instance
+to be the QLineEdit passed in. For simplicity, the QLineEdit is also stored
+in the explicit \c editor member variable.
+
+We then create a QTreeWidget as a toplevel widget and configure the various
+properties to give it the look of a popup widget.
+
+The popup will be populated by the results returned from Google. We set
+the number of columns to be two, since we want to display both the
+suggested search term and the number of hits it will trigger in the search
+engine.
+
+Furthermore, we install the GSuggestCompletion instance as an event filter
+on the QTreeWidget, and connect the \c itemClicked() signal with the \c
+doneCompletion() slot.
+
+A single-shot QTimer is used to start the request when the user has stopped
+typing for 500 ms.
+
+Finally, we connect the networkManagers \c finished() signal with the \c
+handleNetworkData() slot to handle the incoming data.
+
+\snippet examples/network/googlesuggest/googlesuggest.cpp 2
+
+Since the QTreeWidget popup has been instantiated as a toplevel widget, the
+destructor has to delete it explicitly from memory to avoid a memory leak.
+
+\snippet examples/network/googlesuggest/googlesuggest.cpp 3
+
+The event filter handles mouse press and key press events that are
+delivered to the popup. For mouse press events we just hide the popup and
+return focus to the editor widget, and then return true to prevent further
+event processing.
+
+Key event handling is implemented so that Enter and Return execute the
+selected link, while the Escape key hides the popup. Sine we want to be
+able to navigate the list of suggestions using the different navigation
+keys on the keyboard we let Qt continue regular event processing for those
+by returning false from the eventFilter reimplementation.
+
+For all other keys, the event will be passed on to the editor widget and the
+popup is hidden. This way the user's typing will not be interrupted by the
+popping up of the completion list.
+
+\snippet examples/network/googlesuggest/googlesuggest.cpp 4
+
+The \c showCompletion() function populates the QTreeWidget with the results
+returned from the query. It takes two QStringLists, one with the suggested
+search terms and the other with the corresponding number of hits.
+
+\snippet examples/network/googlesuggest/googlesuggest.cpp 5
+
+A QTreeWidgetItem is created for each index in the list and inserted into
+the QTreeWidget. Finally, we adjust position and size of the popup to make
+sure that it pops up in the correct position below the editor, and show it.
+
+The \c doneCompletion() function, which is called by the event filter when
+either Enter or Return keys are pressed, stops the timer to prevent further
+requests and passes the text of the selected item to the editor. We then
+make the \c editor QLineEdit emit the returnPressed() signal, to which the
+application can connect to open the respective web page.
+
+\snippet examples/network/googlesuggest/googlesuggest.cpp 6
+
+The \c autoSuggest() slot is called when the timer times out, and uses the
+text in the editor to build the complete search query. The query is then
+passed to the QNetworkAccessManager's \c get() function to start the
+request.
+
+\snippet examples/network/googlesuggest/googlesuggest.cpp 7
+
+The function \c preventSuggest() stops the timer to prevent further
+requests from being started.
+
+\snippet examples/network/googlesuggest/googlesuggest.cpp 8
+
+When the network request is finished, the QNetworkAccessManager delivers the
+data received from the server through the networkReply object.
+
+\snippet examples/network/googlesuggest/googlesuggest.cpp 9
+
+To extract the data from the reply we use the \c readAll() function, which
+is inherited from QIODevice and returns a QByteArray. Since this data is
+encoded in XML we can use a QXmlStreamReader to traverse the data and
+extract the search result as QStrings, which we can stream into two
+QStringLists used to populate the popup.
+
+Finally, we schedule the QNetworkReply object for deletion using the \c
+deleteLater function.
+
+\section1 SearchBox Class Declaration
+
+The SearchBox class inherits QLineEdit and adds the protected slot \c
+doSearch().
+
+A \c GSuggestCompletion member provides the SearchBox with the request
+functionality and the suggestions returned from the Google search engine.
+
+\snippet examples/network/googlesuggest/searchbox.h 1
+
+\section1 SearchBox Class Implementation
+
+The search box constructor instantiates the GSuggestCompletion object and
+connects the returnPressed() signal to the doSearch() slot.
+
+\snippet examples/network/googlesuggest/searchbox.cpp 1
+
+The function \c doSearch() stops the completer from sending any further
+queries to the search engine.
+
+Further, the function extracts the selected search phrase and opens it in
+the default web browser using QDesktopServices.
+
+\snippet examples/network/googlesuggest/searchbox.cpp 2
+
 */