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diff --git a/doc/src/examples/shapedclock.qdoc b/doc/src/examples/shapedclock.qdoc deleted file mode 100644 index b83178b44d..0000000000 --- a/doc/src/examples/shapedclock.qdoc +++ /dev/null @@ -1,131 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). -** Contact: http://www.qt-project.org/ -** -** This file is part of the documentation of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:FDL$ -** GNU Free Documentation License -** Alternatively, this file may be used under the terms of the GNU Free -** Documentation License version 1.3 as published by the Free Software -** Foundation and appearing in the file included in the packaging of -** this file. -** -** Other Usage -** Alternatively, this file may be used in accordance with the terms -** and conditions contained in a signed written agreement between you -** and Nokia. -** -** -** -** -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \example widgets/shapedclock - \title Shaped Clock Example - - The Shaped Clock example shows how to apply a widget mask to a top-level - widget to produce a shaped window. - - \image shapedclock-example.png - - Widget masks are used to customize the shapes of top-level widgets by restricting - the available area for painting. On some window systems, setting certain window flags - will cause the window decoration (title bar, window frame, buttons) to be disabled, - allowing specially-shaped windows to be created. In this example, we use this feature - to create a circular window containing an analog clock. - - Since this example's window does not provide a \uicontrol File menu or a close - button, we provide a context menu with an \uicontrol Exit entry so that the example - can be closed. Click the right mouse button over the window to open this menu. - - \section1 ShapedClock Class Definition - - The \c ShapedClock class is based on the \c AnalogClock class defined in the - \l{Analog Clock Example}{Analog Clock} example. The whole class definition is - presented below: - - \snippet examples/widgets/shapedclock/shapedclock.h 0 - - The \l{QWidget::paintEvent()}{paintEvent()} implementation is the same as that found - in the \c AnalogClock class. We implement \l{QWidget::sizeHint()}{sizeHint()} - so that we don't have to resize the widget explicitly. We also provide an event - handler for resize events. This allows us to update the mask if the clock is resized. - - Since the window containing the clock widget will have no title bar, we provide - implementations for \l{QWidget::mouseMoveEvent()}{mouseMoveEvent()} and - \l{QWidget::mousePressEvent()}{mousePressEvent()} to allow the clock to be dragged - around the screen. The \c dragPosition variable lets us keep track of where the user - last clicked on the widget. - - \section1 ShapedClock Class Implementation - - The \c ShapedClock constructor performs many of the same tasks as the \c AnalogClock - constructor. We set up a timer and connect it to the widget's update() slot: - - \snippet examples/widgets/shapedclock/shapedclock.cpp 0 - - We inform the window manager that the widget is not to be decorated with a window - frame by setting the Qt::FramelessWindowHint flag on the widget. As a result, we need - to provide a way for the user to move the clock around the screen. - - Mouse button events are delivered to the \c mousePressEvent() handler: - - \snippet examples/widgets/shapedclock/shapedclock.cpp 1 - - If the left mouse button is pressed over the widget, we record the displacement in - global (screen) coordinates between the top-left position of the widget's frame (even - when hidden) and the point where the mouse click occurred. This displacement will be - used if the user moves the mouse while holding down the left button. Since we acted - on the event, we accept it by calling its \l{QEvent::accept()}{accept()} function. - - \image shapedclock-dragging.png - - The \c mouseMoveEvent() handler is called if the mouse is moved over the widget. - - \snippet examples/widgets/shapedclock/shapedclock.cpp 2 - - If the left button is held down while the mouse is moved, the top-left corner of the - widget is moved to the point given by subtracting the \c dragPosition from the current - cursor position in global coordinates. If we drag the widget, we also accept the event. - - The \c paintEvent() function is given for completeness. See the - \l{Analog Clock Example}{Analog Clock} example for a description of the process used - to render the clock. - - \snippet examples/widgets/shapedclock/shapedclock.cpp 3 - - In the \c resizeEvent() handler, we re-use some of the code from the \c paintEvent() - to determine the region of the widget that is visible to the user: - - \snippet examples/widgets/shapedclock/shapedclock.cpp 4 - - Since the clock face is a circle drawn in the center of the widget, this is the region - we use as the mask. - - Although the lack of a window frame may make it difficult for the user to resize the - widget on some platforms, it will not necessarily be impossible. The \c resizeEvent() - function ensures that the widget mask will always be updated if the widget's dimensions - change, and additionally ensures that it will be set up correctly when the widget is - first displayed. - - Finally, we implement the \c sizeHint() for the widget so that it is given a reasonable - default size when it is first shown: - - \snippet examples/widgets/shapedclock/shapedclock.cpp 5 - - \section1 Notes on Widget Masks - - Since QRegion allows arbitrarily complex regions to be created, widget masks can be - made to suit the most unconventionally-shaped windows, and even allow widgets to be - displayed with holes in them. - - Widget masks can also be constructed by using the contents of pixmap to define the - opaque part of the widget. For a pixmap with an alpha channel, a suitable mask can be - obtained with QPixmap::mask(). -*/ |