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diff --git a/examples/widgets/doc/src/findfiles.qdoc b/examples/widgets/doc/src/findfiles.qdoc deleted file mode 100644 index d7428e7d16..0000000000 --- a/examples/widgets/doc/src/findfiles.qdoc +++ /dev/null @@ -1,293 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2016 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** This file is part of the documentation of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:FDL$ -** Commercial License Usage -** Licensees holding valid commercial Qt licenses may use this file in -** accordance with the commercial license agreement provided with the -** Software or, alternatively, in accordance with the terms contained in -** a written agreement between you and The Qt Company. For licensing terms -** and conditions see https://www.qt.io/terms-conditions. For further -** information use the contact form at https://www.qt.io/contact-us. -** -** GNU Free Documentation License Usage -** 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. Please review the following information to ensure -** the GNU Free Documentation License version 1.3 requirements -** will be met: https://www.gnu.org/licenses/fdl-1.3.html. -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \example dialogs/findfiles - \title Find Files Example - \ingroup examples-dialogs - - \brief A dialog for finding files in a specified folder. - - The Find Files application allows the user to search for files in a - specified directory, matching a given file name or wildcard, - and containing a specified string (if filled in). The search - result is displayed in a table containing the names of the files - and their sizes. The application also shows the number of files found. - - The Find Files example illustrates the use of several classes: - - \table - \row - \li QProgressDialog - \li Provide feedback on the progress of a search operation - \row - \li QFileDialog - \li Browse through a file list - \row - \li QTextStream - \li Use stream operators to read a file - \row - \li QTableWidget - \li Browse through the search results in a table - \row - \li QDesktopServices - \li Open files in the result list in a suitable application - \endtable - - \image findfiles-example.png Screenshot of the Find Files example - - - \section1 Window Class Definition - - The \c Window class inherits QWidget, and is the main application - widget. It shows the search options and displays the search - results. - - \snippet dialogs/findfiles/window.h 0 - - The application has two private slots: - \table - \row - \li The \c browse() slot - \li Called whenever the user wants to browse for a directory to search in - \row - \li The \c find() slot - \li Called whenever the user launches a search with the \uicontrol Find button - \endtable - - In addition we declare several private functions: - - \table - \row - \li findFiles() - \li Search for files matching the search parameters - \row - \li showFiles() - \li Display the search result - \row - \li ceateButton() - \li Construct the widget - \row - \li createComboBox() - \li Construct the widget - \row - \li createFilesTable() - \li Construct the widget - \endtable - - \section1 Window Class Implementation - - In the constructor we first create the application's widgets. - - \snippet dialogs/findfiles/window.cpp 0 - - We create the widgets to build up the UI, and we add them to a main layout - using QGridLayout. We have, however, put the \c Find and \c Quit buttons - and a stretchable space in a separate \l QHBoxLayout first, to make the - buttons appear in the \c Window widget's bottom right corner. - - Alternatively, we could have used Qt Designer to construct a UI file, - and \l {uic} to generate this code. - - \snippet dialogs/findfiles/window.cpp 1 - - We did not create a \l QMenuBar with a \uicontrol Quit menu item; but we - would still like to have a keyboard shortcut for quitting. Since we - construct a \l QShortcut with \l QKeySequence::Quit, and connect it to - \l QApplication::quit(), on most platforms it will be possible to press - Control-Q to quit (or whichever standard Quit key is configured on that platform). - (On \macos, this is redundant, because every application gets a - \uicontrol Quit menu item automatically; but it helps to make the application portable.) - - \snippet dialogs/findfiles/window.cpp 2 - - The \c browse() slot presents a file dialog to the user, using the - QFileDialog class. QFileDialog enables a user to traverse the file - system in order to select one or many files or a directory. The - easiest way to create a QFileDialog is to use the convenience - static functions. - - Here we use the static QFileDialog::getExistingDirectory() - function which returns an existing directory selected by the - user. Then we display the directory in the directory combobox - using the QComboBox::addItem() function and update the current - index. - - QComboBox::addItem() adds an item to the combobox with the given - text (if not already present in the list), and containing - the specified userData. The item is appended to the list of - existing items. - - \snippet dialogs/findfiles/window.cpp 3 - - The \c find() slot is called whenever the user requests a new - search by pressing the \uicontrol Find button. - - First we eliminate any previous search results by setting the - table widgets row count to zero. Then we retrieve the - specified file name, text, and directory path from the respective - comboboxes. - - \snippet dialogs/findfiles/window.cpp 4 - - We use the directory's path to create a QDir; the QDir class - provides access to the directory structure and its contents. - - We use QDirIterator to iterate over the files that match the - specified file name and build a QStringList of paths. - - Then we search through all the files in the list, using the private - \c findFiles() function, eliminating the ones that don't contain the - specified text. We sort them (because QDirIterator did not). And finally, - we display the results using the private \c showFiles() function. - - If the user didn't specify any text, there is no reason to search - through the files, so we sort and display the results immediately. - - \image findfiles_progress_dialog.png Screenshot of the Progress Dialog - - \snippet dialogs/findfiles/window.cpp 5 - - In the private \c findFiles() function we search through a list of - files, looking for the ones that contain a specified text. This - can be a very slow operation depending on the number of files as - well as their sizes. QProgressDialog displays a progress dialog - if the application has to search through a large number of files, - or if some of the files have a large size. QProgressDialog can - also allow the user to abort the operation if it takes too much - time. - - \snippet dialogs/findfiles/window.cpp 6 - - We run through the files, one at a time, and for each file we - update the QProgressDialog value. This property holds the current - amount of progress made. We also update the progress dialog's - label. - - Then we call the QCoreApplication::processEvents() function using - the QApplication object. In this way we interleave the display of - the progress made with the process of searching through the files - so the application doesn't appear to be frozen. - - The QApplication class manages the GUI application's control flow - and main settings. It contains the main event loop, where all - events from the window system and other sources are processed and - dispatched. QApplication inherits QCoreApplication. The - QCoreApplication::processEvents() function processes all pending - events according to the specified QEventLoop::ProcessEventFlags - until there are no more events to process. The default flags are - QEventLoop::AllEvents. - - \snippet dialogs/findfiles/window.cpp 7 - - After updating the QProgressDialog, we open the file in read-only - mode, and read one line at a time using QTextStream. - - The QTextStream class provides a convenient interface for reading - and writing text. Using QTextStream's streaming operators, you can - conveniently read and write words, lines and numbers. - - For each line we read we check if the QProgressDialog has been - canceled. If it has, we abort the operation, otherwise we check if - the line contains the specified text. When we find the text within - one of the files, we add the file's name to a list of found files - that contain the specified text, and start searching a new file. - - Finally, we return the list of the files found. - - \snippet dialogs/findfiles/window.cpp 8 - - Both the \c findFiles() and \c showFiles() functions are called from - the \c find() slot. In the \c showFiles() function we run through - the provided list of file names, adding each relative file name to the - first column in the table widget and retrieving the file's size using - QFileInfo for the second column. We use \l QLocale::formattedDataSize() - to format the file size in a human-readable form. For later use, we set - the absolute path as a data on the QTableWidget using the - the role absoluteFileNameRole defined to be Qt::UserRole + 1. - - \snippet dialogs/findfiles/window.cpp 17 - - This allows for retrieving the name of an item using a - convenience function: - - \snippet dialogs/findfiles/window.cpp 18 - - We also update the total number of files found. - - \snippet dialogs/findfiles/window.cpp 10 - - The private \c createComboBox() function is also called from the - contructor. We create a QComboBox with the given text, and make it - editable. - - When the user enters a new string in an editable combobox, the - widget may or may not insert it, and it can insert it in several - locations, depending on the QComboBox::InsertPolicy. The default - policy is is QComboBox::InsertAtBottom. - - Then we add the provided text to the combobox, and specify the - widget's size policies, before we return a pointer to the - combobox. - - \snippet dialogs/findfiles/window.cpp 11 - - The private \c createFilesTable() function is called from the - constructor. In this function we create the QTableWidget that - will display the search results. We set its horizontal headers and - their resize mode. - - QTableWidget inherits QTableView which provides a default - model/view implementation of a table view. The - QTableView::horizontalHeader() function returns the table view's - horizontal header as a QHeaderView. The QHeaderView class provides - a header row or header column for item views, and the - QHeaderView::setResizeMode() function sets the constraints on how - the section in the header can be resized. - - Finally, we hide the QTableWidget's vertical headers using the - QWidget::hide() function, and remove the default grid drawn for - the table using the QTableView::setShowGrid() function. - - \snippet dialogs/findfiles/window.cpp 12 - - \snippet dialogs/findfiles/window.cpp 14 - - The \c openFileOfItem() slot is invoked when the user double - clicks on a cell in the table. The QDesktopServices::openUrl() - knows how to open a file given the file name. - - \snippet dialogs/findfiles/window.cpp 15 - \snippet dialogs/findfiles/window.cpp 16 - - We set the context menu policy to of the table view to Qt::CustomContextMenu - and connect a slot contextMenu() to its signal - customContextMenuRequested(). We retrieve the absolute file name - from the data of the QTableWidgetItem and populate the context menu - with actions offering to copy the file name and to open the file. -*/ - |