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diff --git a/doc/src/examples/dropsite.qdoc b/doc/src/examples/dropsite.qdoc deleted file mode 100644 index 77b40986aa..0000000000 --- a/doc/src/examples/dropsite.qdoc +++ /dev/null @@ -1,249 +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 draganddrop/dropsite - \title Drop Site Example - - The example shows how to distinguish the various MIME formats available - in a drag and drop operation. - - \image dropsite-example.png Screenshot of the Drop Site example - - The Drop Site example accepts drops from other applications, and displays - the MIME formats provided by the drag object. - - There are two classes, \c DropArea and \c DropSiteWindow, and a \c main() - function in this example. A \c DropArea object is instantiated in - \c DropSiteWindow; a \c DropSiteWindow object is then invoked in the - \c main() function. - - \section1 DropArea Class Definition - - The \c DropArea class is a subclass of QLabel with a public slot, - \c clear(), and a \c changed() signal. - - \snippet draganddrop/dropsite/droparea.h DropArea header part1 - - In addition, \c DropArea also contains a private instance of QLabel and - reimplementations of four \l{QWidget} event handlers: - - \list 1 - \li \l{QWidget::dragEnterEvent()}{dragEnterEvent()} - \li \l{QWidget::dragMoveEvent()}{dragMoveEvent()} - \li \l{QWidget::dragLeaveEvent()}{dragLeaveEvent()} - \li \l{QWidget::dropEvent()}{dropEvent()} - \endlist - - These event handlers are further explained in the implementation of the - \c DropArea class. - - \snippet draganddrop/dropsite/droparea.h DropArea header part2 - - \section1 DropArea Class Implementation - - In the \c DropArea constructor, we set the \l{QWidget::setMinimumSize()} - {minimum size} to 200x200 pixels, the \l{QFrame::setFrameStyle()} - {frame style} to both QFrame::Sunken and QFrame::StyledPanel, and we align - its contents to the center. - - \snippet draganddrop/dropsite/droparea.cpp DropArea constructor - - Also, we enable drop events in \c DropArea by setting the - \l{QWidget::acceptDrops()}{acceptDrops} property to \c true. Then, - we enable the \l{QWidget::autoFillBackground()}{autoFillBackground} - property and invoke the \c clear() function. - - The \l{QWidget::dragEnterEvent()}{dragEnterEvent()} event handler is - called when a drag is in progress and the mouse enters the \c DropArea - object. For the \c DropSite example, when the mouse enters \c DropArea, - we set its text to "<drop content>" and highlight its background. - - \snippet draganddrop/dropsite/droparea.cpp dragEnterEvent() function - - Then, we invoke \l{QDropEvent::acceptProposedAction()} - {acceptProposedAction()} on \a event, setting the drop action to the one - proposed. Lastly, we emit the \c changed() signal, with the data that was - dropped and its MIME type information as a parameter. - - For \l{QWidget::dragMoveEvent()}{dragMoveEvent()}, we just accept the - proposed QDragMoveEvent object, \a event, with - \l{QDropEvent::acceptProposedAction()}{acceptProposedAction()}. - - \snippet draganddrop/dropsite/droparea.cpp dragMoveEvent() function - - The \c DropArea class's implementation of \l{QWidget::dropEvent()} - {dropEvent()} extracts the \a{event}'s mime data and displays it - accordingly. - - \snippet draganddrop/dropsite/droparea.cpp dropEvent() function part1 - - The \c mimeData object can contain one of the following objects: an image, - HTML text, plain text, or a list of URLs. - - \snippet draganddrop/dropsite/droparea.cpp dropEvent() function part2 - - \list - \li If \c mimeData contains an image, we display it in \c DropArea with - \l{QLabel::setPixmap()}{setPixmap()}. - \li If \c mimeData contains HTML, we display it with - \l{QLabel::setText()}{setText()} and set \c{DropArea}'s text format - as Qt::RichText. - \li If \c mimeData contains plain text, we display it with - \l{QLabel::setText()}{setText()} and set \c{DropArea}'s text format - as Qt::PlainText. In the event that \c mimeData contains URLs, we - iterate through the list of URLs to display them on individual - lines. - \li If \c mimeData contains other types of objects, we set - \c{DropArea}'s text, with \l{QLabel::setText()}{setText()} to - "Cannot display data" to inform the user. - \endlist - - We then set \c{DropArea}'s \l{QWidget::backgroundRole()}{backgroundRole} to - QPalette::Dark and we accept \c{event}'s proposed action. - - \snippet draganddrop/dropsite/droparea.cpp dropEvent() function part3 - - The \l{QWidget::dragLeaveEvent()}{dragLeaveEvent()} event handler is - called when a drag is in progress and the mouse leaves the widget. - - \snippet draganddrop/dropsite/droparea.cpp dragLeaveEvent() function - - For \c{DropArea}'s implementation, we clear invoke \c clear() and then - accept the proposed event. - - The \c clear() function sets the text in \c DropArea to "<drop content>" - and sets the \l{QWidget::backgroundRole()}{backgroundRole} to - QPalette::Dark. Lastly, it emits the \c changed() signal. - - \snippet draganddrop/dropsite/droparea.cpp clear() function - - \section1 DropSiteWindow Class Definition - - The \c DropSiteWindow class contains a constructor and a public slot, - \c updateFormatsTable(). - - \snippet draganddrop/dropsite/dropsitewindow.h DropSiteWindow header - - The class also contains a private instance of \c DropArea, \c dropArea, - QLabel, \c abstractLabel, QTableWidget, \c formatsTable, QDialogButtonBox, - \c buttonBox, and two QPushButton objects, \c clearButton and - \c quitButton. - - \section1 DropSiteWindow Class Implementation - - In the constructor of \c DropSiteWindow, we instantiate \c abstractLabel - and set its \l{QLabel::setWordWrap()}{wordWrap} property to \c true. We - also call the \l{QLabel::adjustSize()}{adjustSize()} function to adjust - \c{abstractLabel}'s size according to its contents. - - \snippet draganddrop/dropsite/dropsitewindow.cpp constructor part1 - - Then we instantiate \c dropArea and connect its \c changed() signal to - \c{DropSiteWindow}'s \c updateFormatsTable() slot. - - \snippet draganddrop/dropsite/dropsitewindow.cpp constructor part2 - - We now set up the QTableWidget object, \c formatsTable. Its - horizontal header is set using a QStringList object, \c labels. The number - of columms are set to two and the table is not editable. Also, the - \c{formatTable}'s horizontal header is formatted to ensure that its second - column stretches to occupy additional space available. - - \snippet draganddrop/dropsite/dropsitewindow.cpp constructor part3 - - Two QPushButton objects, \c clearButton and \c quitButton, are instantiated - and added to \c buttonBox - a QDialogButtonBox object. We use - QDialogButtonBox here to ensure that the push buttons are presented in a - layout that conforms to the platform's style. - - \snippet draganddrop/dropsite/dropsitewindow.cpp constructor part4 - - The \l{QPushButton::clicked()}{clicked()} signals for \c quitButton and - \c clearButton are connected to \l{QWidget::close()}{close()} and - \c clear(), respectively. - - For the layout, we use a QVBoxLayout, \c mainLayout, to arrange our widgets - vertically. We also set the window title to "Drop Site" and the minimum - size to 350x500 pixels. - - \snippet draganddrop/dropsite/dropsitewindow.cpp constructor part5 - - We move on to the \c updateFormatsTable() function. This function updates - the \c formatsTable, displaying the MIME formats of the object dropped onto - the \c DropArea object. First, we set \l{QTableWidget}'s - \l{QTableWidget::setRowCount()}{rowCount} property to 0. Then, we validate - to ensure that the QMimeData object passed in is a valid object. - - \snippet draganddrop/dropsite/dropsitewindow.cpp updateFormatsTable() part1 - - Once we are sure that \c mimeData is valid, we iterate through its - supported formats using the \l{The foreach Keyword}{foreach keyword}. - This keyword has the following format: - - \snippet doc/src/snippets/code/doc_src_examples_dropsite.qdoc 0 - - In our example, \c format is the \a variable and the \a container is a - QStringList, obtained from \c mimeData->formats(). - - \note The \l{QMimeData::formats()}{formats()} function returns a - QStringList object, containing all the formats supported by the - \c mimeData. - - \snippet draganddrop/dropsite/dropsitewindow.cpp updateFormatsTable() part2 - - Within each iteration, we create a QTableWidgetItem, \c formatItem and we - set its \l{QTableWidgetItem::setFlags()}{flags} to Qt::ItemIsEnabled, and - its \l{QTableWidgetItem::setTextAlignment()}{text alignment} to Qt::AlignTop - and Qt::AlignLeft. - - A QString object, \c text, is customized to display data according to the - contents of \c format. We invoke {QString}'s \l{QString::simplified()} - {simplified()} function on \c text, to obtain a string that has no - additional space before, after or in between words. - - \snippet draganddrop/dropsite/dropsitewindow.cpp updateFormatsTable() part3 - - If \c format contains a list of URLs, we iterate through them, using spaces - to separate them. On the other hand, if \c format contains an image, we - display the data by converting the text to hexadecimal. - - \snippet draganddrop/dropsite/dropsitewindow.cpp updateFormatsTable() part4 - - Once \c text has been customized to contain the appropriate data, we insert - both \c format and \c text into \c formatsTable with - \l{QTableWidget::setItem()}{setItem()}. Lastly, we invoke - \l{QTableView::resizeColumnToContents()}{resizeColumnToContents()} on - \c{formatsTable}'s first column. - - \section1 The main() Function - - Within the \c main() function, we instantiate \c DropSiteWindow and invoke - its \l{QWidget::show()}{show()} function. - - \snippet draganddrop/dropsite/main.cpp main() function -*/ |