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-rw-r--r--doc/src/examples/contiguouscache.qdoc97
-rw-r--r--doc/src/examples/fancybrowser.qdoc103
-rw-r--r--doc/src/layout.qdoc16
-rw-r--r--doc/src/qset.qdoc2
-rw-r--r--doc/src/snippets/code/doc_src_layout.qdoc41
-rw-r--r--doc/src/snippets/sqldatabase/sqldatabase.cpp2
6 files changed, 232 insertions, 29 deletions
diff --git a/doc/src/examples/contiguouscache.qdoc b/doc/src/examples/contiguouscache.qdoc
new file mode 100644
index 0000000..fbfde3f
--- /dev/null
+++ b/doc/src/examples/contiguouscache.qdoc
@@ -0,0 +1,97 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \example tools/contiguouscache
+ \title Contiguous Cache Example
+
+ The Contiguous Cache example shows how to use QContiguousCache to manage memory usage for
+ very large models. In some environments memory is limited and, even when it
+ isn't, users still dislike an application using excessive memory.
+ Using QContiguousCache to manage a list, rather than loading
+ the entire list into memory, allows the application to limit the amount
+ of memory it uses, regardless of the size of the data set it accesses
+
+ The simplest way to use QContiguousCache is to cache as items are requested. When
+ a view requests an item at row N it is also likely to ask for items at rows near
+ to N.
+
+ \snippet examples/tools/contiguouscache/randomlistmodel.cpp 0
+
+ After getting the row, the class determines if the row is in the bounds
+ of the contiguous cache's current range. It would have been equally valid to
+ simply have the following code instead.
+
+ \code
+ while (row > m_rows.lastIndex())
+ m_rows.append(fetchWord(m_rows.lastIndex()+1);
+ while (row < m_rows.firstIndex())
+ m_rows.prepend(fetchWord(m_rows.firstIndex()-1);
+ \endcode
+
+ However a list will often jump rows if the scroll bar is used directly, resulting in
+ the code above causing every row between the old and new rows to be fetched.
+
+ Using QContiguousCache::lastIndex() and QContiguousCache::firstIndex() allows
+ the example to determine what part of the list the cache is currently caching.
+ These values don't represent the indexes into the cache's own memory, but rather
+ a virtual infinite array that the cache represents.
+
+ By using QContiguousCache::append() and QContiguousCache::prepend() the code ensures
+ that items that may be still on the screen are not lost when the requested row
+ has not moved far from the current cache range. QContiguousCache::insert() can
+ potentially remove more than one item from the cache as QContiguousCache does not
+ allow for gaps. If your cache needs to quickly jump back and forth between
+ rows with significant gaps between them consider using QCache instead.
+
+ And thats it. A perfectly reasonable cache, using minimal memory for a very large
+ list. In this case the accessor for getting the words into the cache
+ generates random information rather than fixed information. This allows you
+ to see how the cache range is kept for a local number of rows when running the
+ example.
+
+ \snippet examples/tools/contiguouscache/randomlistmodel.cpp 1
+
+ It is also worth considering pre-fetching items into the cache outside of the
+ application's paint routine. This can be done either with a separate thread
+ or using a QTimer to incrementally expand the range of the cache prior to
+ rows being requested out of the current cache range.
+*/
diff --git a/doc/src/examples/fancybrowser.qdoc b/doc/src/examples/fancybrowser.qdoc
index 9001c20..631aff9 100644
--- a/doc/src/examples/fancybrowser.qdoc
+++ b/doc/src/examples/fancybrowser.qdoc
@@ -40,12 +40,109 @@
****************************************************************************/
/*!
- \example webkit/fancybrowser
- \title Fancy Browser Example
+ \example webkit/fancybrowser
+ \title Fancy Browser Example
The Fancy Browser example shows how to use jQuery with QtWebKit to
- make a web browser with some special effects and content manipulation.
+ create a web browser with special effects and content
+ manipulation.
\image fancybrowser-example.png
+ The application makes use of QWebFrame::evaluateJavaScript to
+ evaluate the jQuery JavaScript code. A QMainWindow with a QWebView
+ as central widget builds up the browser itself.
+
+ \section1 MainWindow Class Definition
+
+ The \c MainWindow class inherits QMainWindow. It implements a number of
+ slots to perform actions on both the application and on the web content.
+
+ \snippet examples/webkit/fancybrowser/mainwindow.h 1
+
+ We also declare a QString that contains the jQuery, a QWebView
+ that displays the web content, and a QLineEdit that acts as the
+ address bar.
+
+ \section1 MainWindow Class Implementation
+
+ We start by implementing the constructor.
+
+ \snippet examples/webkit/fancybrowser/mainwindow.cpp 1
+
+ The first part of the constructor sets the value of \c progress to
+ 0. This value will be used later in the code to visualize the
+ loading of a webpage.
+
+ Next, the jQuery library is loaded using a QFile and reading the file
+ content. The jQuery library is a JavaScript library that provides different
+ functions for manipulating HTML.
+
+ \snippet examples/webkit/fancybrowser/mainwindow.cpp 2
+
+ The second part of the constructor creates a QWebView and connects
+ slots to the views signals. Furthermore, we create a QLineEdit as
+ the browsers address bar. We then set the horizontal QSizePolicy
+ to fill the available area in the browser at all times. We add the
+ QLineEdit to a QToolbar together with a set of navigation actions
+ from QWebView::pageAction.
+
+ \snippet examples/webkit/fancybrowser/mainwindow.cpp 3
+
+ The third and last part of the constructor implements two QMenus and assigns
+ a set of actions to them. The last line sets the QWebView as the central
+ widget in the QMainWindow.
+
+ \snippet examples/webkit/fancybrowser/mainwindow.cpp 4
+
+ When the page is loaded, \c adjustLocation() updates the address
+ bar; \c adjustLocation() is triggered by the \c loadFinished()
+ signal in QWebView. In \c changeLocation() we create a QUrl
+ object, and then use it to load the page into the QWebView. When
+ the new web page has finished loading, \c adjustLocation() will be
+ run once more to update the address bar.
+
+ \snippet examples/webkit/fancybrowser/mainwindow.cpp 5
+
+ \c adjustTitle() sets the window title and displays the loading
+ progress. This slot is triggered by the \c titleChanged() signal
+ in QWebView.
+
+ \snippet examples/webkit/fancybrowser/mainwindow.cpp 6
+
+ When a web page has loaded, \c finishLoading() is triggered by the
+ \c loadFinished() signal in QWebView. \c finishLoading() then updates the
+ progress in the title bar and calls \c evaluateJavaScript() to evaluate the
+ jQuery library. This evaluates the JavaScript against the current web page.
+ What that means is that the JavaScript can be viewed as part of the content
+ loaded into the QWebView, and therefore needs to be loaded every time a new
+ page is loaded. Once the jQuery library is loaded, we can start executing
+ the different jQuery functions in the browser.
+
+ \snippet examples/webkit/fancybrowser/mainwindow.cpp 7
+
+ The first jQuery-based function, \c highlightAllLinks(), is designed to
+ highlight all links in the current webpage. The JavaScript code looks
+ for web elements named \e {a}, which is the tag for a hyperlink.
+ For each such element, the background color is set to be yellow by
+ using CSS.
+
+ \snippet examples/webkit/fancybrowser/mainwindow.cpp 8
+
+ The \c rotateImages() function rotates the images on the current
+ web page. Webkit supports CSS transforms and this JavaScript code
+ looks up all \e {img} elements and rotates the images 180 degrees
+ and then back again.
+
+ \snippet examples/webkit/fancybrowser/mainwindow.cpp 9
+
+ The remaining four methods remove different elements from the current web
+ page. \c removeGifImages() removes all Gif images on the page by looking up
+ the \e {src} attribute of all the elements on the web page. Any element with
+ a \e {gif} file as its source is removed. \c removeInlineFrames() removes all
+ \e {iframe} or inline elements. \c removeObjectElements() removes all
+ \e {object} elements, and \c removeEmbeddedElements() removes any elements
+ such as plugins embedded on the page using the \e {embed} tag.
+
*/
+
diff --git a/doc/src/layout.qdoc b/doc/src/layout.qdoc
index 55dfd8b..196999b 100644
--- a/doc/src/layout.qdoc
+++ b/doc/src/layout.qdoc
@@ -315,7 +315,11 @@
\snippet doc/src/snippets/code/doc_src_layout.qdoc 1
- First we define two functions that iterate over the layout: \c{itemAt()}
+ First we define \c{count()} to fetch the number of items in the list.
+
+ \snippet doc/src/snippets/code/doc_src_layout.qdoc 2
+
+ Then we define two functions that iterate over the layout: \c{itemAt()}
and \c{takeAt()}. These functions are used internally by the layout system
to handle deletion of widgets. They are also available for application
programmers.
@@ -326,7 +330,7 @@
structure, we may have to spend more effort defining a linear order for the
items.
- \snippet doc/src/snippets/code/doc_src_layout.qdoc 2
+ \snippet doc/src/snippets/code/doc_src_layout.qdoc 3
\c{addItem()} implements the default placement strategy for layout items.
This function must be implemented. It is used by QLayout::add(), by the
@@ -336,26 +340,26 @@
QGridLayout::addItem(), QGridLayout::addWidget(), and
QGridLayout::addLayout().
- \snippet doc/src/snippets/code/doc_src_layout.qdoc 3
+ \snippet doc/src/snippets/code/doc_src_layout.qdoc 4
The layout takes over responsibility of the items added. Since QLayoutItem
does not inherit QObject, we must delete the items manually. The function
QLayout::deleteAllItems() uses \c{takeAt()} defined above to delete all the
items in the layout.
- \snippet doc/src/snippets/code/doc_src_layout.qdoc 4
+ \snippet doc/src/snippets/code/doc_src_layout.qdoc 5
The \c{setGeometry()} function actually performs the layout. The rectangle
supplied as an argument does not include \c{margin()}. If relevant, use
\c{spacing()} as the distance between items.
- \snippet doc/src/snippets/code/doc_src_layout.qdoc 5
+ \snippet doc/src/snippets/code/doc_src_layout.qdoc 6
\c{sizeHint()} and \c{minimumSize()} are normally very similar in
implementation. The sizes returned by both functions should include
\c{spacing()}, but not \c{margin()}.
- \snippet doc/src/snippets/code/doc_src_layout.qdoc 6
+ \snippet doc/src/snippets/code/doc_src_layout.qdoc 7
\section2 Further Notes
diff --git a/doc/src/qset.qdoc b/doc/src/qset.qdoc
index 9795123..2d12661 100644
--- a/doc/src/qset.qdoc
+++ b/doc/src/qset.qdoc
@@ -447,7 +447,7 @@
\fn QSet::const_iterator QSet::insert(const T &value)
Inserts item \a value into the set, if \a value isn't already
- in the set, and returns an iterator positioned at the inserted
+ in the set, and returns an iterator pointing at the inserted
item.
\sa operator<<(), remove(), contains()
diff --git a/doc/src/snippets/code/doc_src_layout.qdoc b/doc/src/snippets/code/doc_src_layout.qdoc
index 48e10e9..fedcf0c 100644
--- a/doc/src/snippets/code/doc_src_layout.qdoc
+++ b/doc/src/snippets/code/doc_src_layout.qdoc
@@ -2,23 +2,21 @@
#ifndef CARD_H
#define CARD_H
-#include <QLayout>
+#include <QtGui>
#include <QList>
class CardLayout : public QLayout
{
public:
- CardLayout(QWidget *parent, int dist)
- : QLayout(parent, 0, dist) {}
- CardLayout(QLayout *parent, int dist)
- : QLayout(parent, dist) {}
- CardLayout(int dist)
- : QLayout(dist) {}
+ CardLayout(QWidget *parent, int dist): QLayout(parent, 0, dist) {}
+ CardLayout(QLayout *parent, int dist): QLayout(parent, dist) {}
+ CardLayout(int dist): QLayout(dist) {}
~CardLayout();
void addItem(QLayoutItem *item);
QSize sizeHint() const;
QSize minimumSize() const;
+ QLayoutItem *count() const;
QLayoutItem *itemAt(int) const;
QLayoutItem *takeAt(int);
void setGeometry(const QRect &rect);
@@ -31,11 +29,18 @@ private:
//! [1]
-#include "card.h"
+//#include "card.h"
//! [1]
-
//! [2]
+QLayoutItem *CardLayout::count() const
+{
+ // QList::size() returns the number of QLayoutItems in the list
+ return list.size();
+}
+//! [2]
+
+//! [3]
QLayoutItem *CardLayout::itemAt(int idx) const
{
// QList::value() performs index checking, and returns 0 if we are
@@ -48,26 +53,26 @@ QLayoutItem *CardLayout::takeAt(int idx)
// QList::take does not do index checking
return idx >= 0 && idx < list.size() ? list.takeAt(idx) : 0;
}
-//! [2]
+//! [3]
-//! [3]
+//! [4]
void CardLayout::addItem(QLayoutItem *item)
{
list.append(item);
}
-//! [3]
+//! [4]
-//! [4]
+//! [5]
CardLayout::~CardLayout()
{
deleteAllItems();
}
-//! [4]
+//! [5]
-//! [5]
+//! [6]
void CardLayout::setGeometry(const QRect &r)
{
QLayout::setGeometry(r);
@@ -85,10 +90,10 @@ void CardLayout::setGeometry(const QRect &r)
++i;
}
}
-//! [5]
+//! [6]
-//! [6]
+//! [7]
QSize CardLayout::sizeHint() const
{
QSize s(0,0);
@@ -116,4 +121,4 @@ QSize CardLayout::minimumSize() const
}
return s + n*QSize(spacing(), spacing());
}
-//! [6]
+//! [7] \ No newline at end of file
diff --git a/doc/src/snippets/sqldatabase/sqldatabase.cpp b/doc/src/snippets/sqldatabase/sqldatabase.cpp
index ae176ac..06afa0c 100644
--- a/doc/src/snippets/sqldatabase/sqldatabase.cpp
+++ b/doc/src/snippets/sqldatabase/sqldatabase.cpp
@@ -524,7 +524,7 @@ protected:
bool fetchLast() { return false; }
int size() { return 0; }
int numRowsAffected() { return 0; }
- QSqlRecord record() { return QSqlRecord(); }
+ QSqlRecord record() const { return QSqlRecord(); }
};
//! [47]
generated by cgit v0.12 at 2025-01-30 16:13:45 (GMT)