<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>mainwindow.cpp Example File | Qt Widgets 5.12.6</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.12</td><td ><a href="qtwidgets-index.html">Qt Widgets</a></td><td ><a href="qtwidgets-mainwindows-application-example.html">Application Example</a></td><td >mainwindow.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtwidgets-index.html">Qt 5.12.6 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"><div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">mainwindow.cpp Example File</h1> <span class="subtitle">mainwindows/application/mainwindow.cpp</span> <!-- $$$mainwindows/application/mainwindow.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** 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. ** ** BSD License Usage ** Alternatively, you may use this file under the terms of the BSD license ** as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of The Qt Company Ltd nor the names of its ** contributors may be used to endorse or promote products derived ** from this software without specific prior written permission. ** ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include <QtWidgets></span> <span class="preprocessor">#include "mainwindow.h"</span> MainWindow<span class="operator">::</span>MainWindow() : textEdit(<span class="keyword">new</span> <span class="type"><a href="qplaintextedit.html">QPlainTextEdit</a></span>) { setCentralWidget(textEdit); createActions(); createStatusBar(); readSettings(); connect(textEdit<span class="operator">-</span><span class="operator">></span>document()<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="../qtgui/qtextdocument.html">QTextDocument</a></span><span class="operator">::</span>contentsChanged<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>MainWindow<span class="operator">::</span>documentWasModified); <span class="preprocessor">#ifndef QT_NO_SESSIONMANAGER</span> <span class="type"><a href="../qtgui/qguiapplication.html">QGuiApplication</a></span><span class="operator">::</span>setFallbackSessionManagementEnabled(<span class="keyword">false</span>); connect(<a href="qapplication.html#qApp">qApp</a><span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="../qtgui/qguiapplication.html">QGuiApplication</a></span><span class="operator">::</span>commitDataRequest<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>MainWindow<span class="operator">::</span>commitData); <span class="preprocessor">#endif</span> setCurrentFile(<span class="type"><a href="../qtcore/qstring.html">QString</a></span>()); setUnifiedTitleAndToolBarOnMac(<span class="keyword">true</span>); } <span class="type">void</span> MainWindow<span class="operator">::</span>closeEvent(<span class="type"><a href="../qtgui/qcloseevent.html">QCloseEvent</a></span> <span class="operator">*</span>event) { <span class="keyword">if</span> (maybeSave()) { writeSettings(); event<span class="operator">-</span><span class="operator">></span>accept(); } <span class="keyword">else</span> { event<span class="operator">-</span><span class="operator">></span>ignore(); } } <span class="type">void</span> MainWindow<span class="operator">::</span>newFile() { <span class="keyword">if</span> (maybeSave()) { textEdit<span class="operator">-</span><span class="operator">></span>clear(); setCurrentFile(<span class="type"><a href="../qtcore/qstring.html">QString</a></span>()); } } <span class="type">void</span> MainWindow<span class="operator">::</span>open() { <span class="keyword">if</span> (maybeSave()) { <span class="type"><a href="../qtcore/qstring.html">QString</a></span> fileName <span class="operator">=</span> <span class="type"><a href="qfiledialog.html">QFileDialog</a></span><span class="operator">::</span>getOpenFileName(<span class="keyword">this</span>); <span class="keyword">if</span> (<span class="operator">!</span>fileName<span class="operator">.</span>isEmpty()) loadFile(fileName); } } bool MainWindow<span class="operator">::</span>save() { <span class="keyword">if</span> (curFile<span class="operator">.</span>isEmpty()) { <span class="keyword">return</span> saveAs(); } <span class="keyword">else</span> { <span class="keyword">return</span> saveFile(curFile); } } bool MainWindow<span class="operator">::</span>saveAs() { <span class="type"><a href="qfiledialog.html">QFileDialog</a></span> dialog(<span class="keyword">this</span>); dialog<span class="operator">.</span>setWindowModality(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>WindowModal); dialog<span class="operator">.</span>setAcceptMode(<span class="type"><a href="qfiledialog.html">QFileDialog</a></span><span class="operator">::</span>AcceptSave); <span class="keyword">if</span> (dialog<span class="operator">.</span>exec() <span class="operator">!</span><span class="operator">=</span> <span class="type"><a href="qdialog.html">QDialog</a></span><span class="operator">::</span>Accepted) <span class="keyword">return</span> <span class="keyword">false</span>; <span class="keyword">return</span> saveFile(dialog<span class="operator">.</span>selectedFiles()<span class="operator">.</span>first()); } <span class="type">void</span> MainWindow<span class="operator">::</span>about() { <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>about(<span class="keyword">this</span><span class="operator">,</span> tr(<span class="string">"About Application"</span>)<span class="operator">,</span> tr(<span class="string">"The <b>Application</b> example demonstrates how to "</span> <span class="string">"write modern GUI applications using Qt, with a menu bar, "</span> <span class="string">"toolbars, and a status bar."</span>)); } <span class="type">void</span> MainWindow<span class="operator">::</span>documentWasModified() { setWindowModified(textEdit<span class="operator">-</span><span class="operator">></span>document()<span class="operator">-</span><span class="operator">></span>isModified()); } <span class="type">void</span> MainWindow<span class="operator">::</span>createActions() { <span class="type"><a href="qmenu.html">QMenu</a></span> <span class="operator">*</span>fileMenu <span class="operator">=</span> menuBar()<span class="operator">-</span><span class="operator">></span>addMenu(tr(<span class="string">"&File"</span>)); <span class="type"><a href="qtoolbar.html">QToolBar</a></span> <span class="operator">*</span>fileToolBar <span class="operator">=</span> addToolBar(tr(<span class="string">"File"</span>)); <span class="keyword">const</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span> newIcon <span class="operator">=</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span><span class="operator">::</span>fromTheme(<span class="string">"document-new"</span><span class="operator">,</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span>(<span class="string">":/images/new.png"</span>)); <span class="type"><a href="qaction.html">QAction</a></span> <span class="operator">*</span>newAct <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(newIcon<span class="operator">,</span> tr(<span class="string">"&New"</span>)<span class="operator">,</span> <span class="keyword">this</span>); newAct<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>New); newAct<span class="operator">-</span><span class="operator">></span>setStatusTip(tr(<span class="string">"Create a new file"</span>)); connect(newAct<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qaction.html">QAction</a></span><span class="operator">::</span>triggered<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>MainWindow<span class="operator">::</span>newFile); fileMenu<span class="operator">-</span><span class="operator">></span>addAction(newAct); fileToolBar<span class="operator">-</span><span class="operator">></span>addAction(newAct); <span class="keyword">const</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span> openIcon <span class="operator">=</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span><span class="operator">::</span>fromTheme(<span class="string">"document-open"</span><span class="operator">,</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span>(<span class="string">":/images/open.png"</span>)); <span class="type"><a href="qaction.html">QAction</a></span> <span class="operator">*</span>openAct <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(openIcon<span class="operator">,</span> tr(<span class="string">"&Open..."</span>)<span class="operator">,</span> <span class="keyword">this</span>); openAct<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>Open); openAct<span class="operator">-</span><span class="operator">></span>setStatusTip(tr(<span class="string">"Open an existing file"</span>)); connect(openAct<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qaction.html">QAction</a></span><span class="operator">::</span>triggered<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>MainWindow<span class="operator">::</span>open); fileMenu<span class="operator">-</span><span class="operator">></span>addAction(openAct); fileToolBar<span class="operator">-</span><span class="operator">></span>addAction(openAct); <span class="keyword">const</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span> saveIcon <span class="operator">=</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span><span class="operator">::</span>fromTheme(<span class="string">"document-save"</span><span class="operator">,</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span>(<span class="string">":/images/save.png"</span>)); <span class="type"><a href="qaction.html">QAction</a></span> <span class="operator">*</span>saveAct <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(saveIcon<span class="operator">,</span> tr(<span class="string">"&Save"</span>)<span class="operator">,</span> <span class="keyword">this</span>); saveAct<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>Save); saveAct<span class="operator">-</span><span class="operator">></span>setStatusTip(tr(<span class="string">"Save the document to disk"</span>)); connect(saveAct<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qaction.html">QAction</a></span><span class="operator">::</span>triggered<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>MainWindow<span class="operator">::</span>save); fileMenu<span class="operator">-</span><span class="operator">></span>addAction(saveAct); fileToolBar<span class="operator">-</span><span class="operator">></span>addAction(saveAct); <span class="keyword">const</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span> saveAsIcon <span class="operator">=</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span><span class="operator">::</span>fromTheme(<span class="string">"document-save-as"</span>); <span class="type"><a href="qaction.html">QAction</a></span> <span class="operator">*</span>saveAsAct <span class="operator">=</span> fileMenu<span class="operator">-</span><span class="operator">></span>addAction(saveAsIcon<span class="operator">,</span> tr(<span class="string">"Save &As..."</span>)<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>MainWindow<span class="operator">::</span>saveAs); saveAsAct<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>SaveAs); saveAsAct<span class="operator">-</span><span class="operator">></span>setStatusTip(tr(<span class="string">"Save the document under a new name"</span>)); fileMenu<span class="operator">-</span><span class="operator">></span>addSeparator(); <span class="keyword">const</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span> exitIcon <span class="operator">=</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span><span class="operator">::</span>fromTheme(<span class="string">"application-exit"</span>); <span class="type"><a href="qaction.html">QAction</a></span> <span class="operator">*</span>exitAct <span class="operator">=</span> fileMenu<span class="operator">-</span><span class="operator">></span>addAction(exitIcon<span class="operator">,</span> tr(<span class="string">"E&xit"</span>)<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qwidget.html">QWidget</a></span><span class="operator">::</span>close); exitAct<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>Quit); exitAct<span class="operator">-</span><span class="operator">></span>setStatusTip(tr(<span class="string">"Exit the application"</span>)); <span class="type"><a href="qmenu.html">QMenu</a></span> <span class="operator">*</span>editMenu <span class="operator">=</span> menuBar()<span class="operator">-</span><span class="operator">></span>addMenu(tr(<span class="string">"&Edit"</span>)); <span class="type"><a href="qtoolbar.html">QToolBar</a></span> <span class="operator">*</span>editToolBar <span class="operator">=</span> addToolBar(tr(<span class="string">"Edit"</span>)); <span class="preprocessor">#ifndef QT_NO_CLIPBOARD</span> <span class="keyword">const</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span> cutIcon <span class="operator">=</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span><span class="operator">::</span>fromTheme(<span class="string">"edit-cut"</span><span class="operator">,</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span>(<span class="string">":/images/cut.png"</span>)); <span class="type"><a href="qaction.html">QAction</a></span> <span class="operator">*</span>cutAct <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(cutIcon<span class="operator">,</span> tr(<span class="string">"Cu&t"</span>)<span class="operator">,</span> <span class="keyword">this</span>); cutAct<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>Cut); cutAct<span class="operator">-</span><span class="operator">></span>setStatusTip(tr(<span class="string">"Cut the current selection's contents to the "</span> <span class="string">"clipboard"</span>)); connect(cutAct<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qaction.html">QAction</a></span><span class="operator">::</span>triggered<span class="operator">,</span> textEdit<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qplaintextedit.html">QPlainTextEdit</a></span><span class="operator">::</span>cut); editMenu<span class="operator">-</span><span class="operator">></span>addAction(cutAct); editToolBar<span class="operator">-</span><span class="operator">></span>addAction(cutAct); <span class="keyword">const</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span> copyIcon <span class="operator">=</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span><span class="operator">::</span>fromTheme(<span class="string">"edit-copy"</span><span class="operator">,</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span>(<span class="string">":/images/copy.png"</span>)); <span class="type"><a href="qaction.html">QAction</a></span> <span class="operator">*</span>copyAct <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(copyIcon<span class="operator">,</span> tr(<span class="string">"&Copy"</span>)<span class="operator">,</span> <span class="keyword">this</span>); copyAct<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>Copy); copyAct<span class="operator">-</span><span class="operator">></span>setStatusTip(tr(<span class="string">"Copy the current selection's contents to the "</span> <span class="string">"clipboard"</span>)); connect(copyAct<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qaction.html">QAction</a></span><span class="operator">::</span>triggered<span class="operator">,</span> textEdit<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qplaintextedit.html">QPlainTextEdit</a></span><span class="operator">::</span>copy); editMenu<span class="operator">-</span><span class="operator">></span>addAction(copyAct); editToolBar<span class="operator">-</span><span class="operator">></span>addAction(copyAct); <span class="keyword">const</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span> pasteIcon <span class="operator">=</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span><span class="operator">::</span>fromTheme(<span class="string">"edit-paste"</span><span class="operator">,</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span>(<span class="string">":/images/paste.png"</span>)); <span class="type"><a href="qaction.html">QAction</a></span> <span class="operator">*</span>pasteAct <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(pasteIcon<span class="operator">,</span> tr(<span class="string">"&Paste"</span>)<span class="operator">,</span> <span class="keyword">this</span>); pasteAct<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>Paste); pasteAct<span class="operator">-</span><span class="operator">></span>setStatusTip(tr(<span class="string">"Paste the clipboard's contents into the current "</span> <span class="string">"selection"</span>)); connect(pasteAct<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qaction.html">QAction</a></span><span class="operator">::</span>triggered<span class="operator">,</span> textEdit<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qplaintextedit.html">QPlainTextEdit</a></span><span class="operator">::</span>paste); editMenu<span class="operator">-</span><span class="operator">></span>addAction(pasteAct); editToolBar<span class="operator">-</span><span class="operator">></span>addAction(pasteAct); menuBar()<span class="operator">-</span><span class="operator">></span>addSeparator(); <span class="preprocessor">#endif // !QT_NO_CLIPBOARD</span> <span class="type"><a href="qmenu.html">QMenu</a></span> <span class="operator">*</span>helpMenu <span class="operator">=</span> menuBar()<span class="operator">-</span><span class="operator">></span>addMenu(tr(<span class="string">"&Help"</span>)); <span class="type"><a href="qaction.html">QAction</a></span> <span class="operator">*</span>aboutAct <span class="operator">=</span> helpMenu<span class="operator">-</span><span class="operator">></span>addAction(tr(<span class="string">"&About"</span>)<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>MainWindow<span class="operator">::</span>about); aboutAct<span class="operator">-</span><span class="operator">></span>setStatusTip(tr(<span class="string">"Show the application's About box"</span>)); <span class="type"><a href="qaction.html">QAction</a></span> <span class="operator">*</span>aboutQtAct <span class="operator">=</span> helpMenu<span class="operator">-</span><span class="operator">></span>addAction(tr(<span class="string">"About &Qt"</span>)<span class="operator">,</span> <a href="qapplication.html#qApp">qApp</a><span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qapplication.html">QApplication</a></span><span class="operator">::</span>aboutQt); aboutQtAct<span class="operator">-</span><span class="operator">></span>setStatusTip(tr(<span class="string">"Show the Qt library's About box"</span>)); <span class="preprocessor">#ifndef QT_NO_CLIPBOARD</span> cutAct<span class="operator">-</span><span class="operator">></span>setEnabled(<span class="keyword">false</span>); copyAct<span class="operator">-</span><span class="operator">></span>setEnabled(<span class="keyword">false</span>); connect(textEdit<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qplaintextedit.html">QPlainTextEdit</a></span><span class="operator">::</span>copyAvailable<span class="operator">,</span> cutAct<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qaction.html">QAction</a></span><span class="operator">::</span>setEnabled); connect(textEdit<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qplaintextedit.html">QPlainTextEdit</a></span><span class="operator">::</span>copyAvailable<span class="operator">,</span> copyAct<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qaction.html">QAction</a></span><span class="operator">::</span>setEnabled); <span class="preprocessor">#endif // !QT_NO_CLIPBOARD</span> } <span class="type">void</span> MainWindow<span class="operator">::</span>createStatusBar() { statusBar()<span class="operator">-</span><span class="operator">></span>showMessage(tr(<span class="string">"Ready"</span>)); } <span class="type">void</span> MainWindow<span class="operator">::</span>readSettings() { <span class="type"><a href="../qtcore/qsettings.html">QSettings</a></span> settings(<span class="type"><a href="../qtcore/qcoreapplication.html">QCoreApplication</a></span><span class="operator">::</span>organizationName()<span class="operator">,</span> <span class="type"><a href="../qtcore/qcoreapplication.html">QCoreApplication</a></span><span class="operator">::</span>applicationName()); <span class="keyword">const</span> <span class="type"><a href="../qtcore/qbytearray.html">QByteArray</a></span> geometry <span class="operator">=</span> settings<span class="operator">.</span>value(<span class="string">"geometry"</span><span class="operator">,</span> <span class="type"><a href="../qtcore/qbytearray.html">QByteArray</a></span>())<span class="operator">.</span>toByteArray(); <span class="keyword">if</span> (geometry<span class="operator">.</span>isEmpty()) { <span class="keyword">const</span> <span class="type"><a href="../qtcore/qrect.html">QRect</a></span> availableGeometry <span class="operator">=</span> <span class="type"><a href="qapplication.html">QApplication</a></span><span class="operator">::</span>desktop()<span class="operator">-</span><span class="operator">></span>availableGeometry(<span class="keyword">this</span>); resize(availableGeometry<span class="operator">.</span>width() <span class="operator">/</span> <span class="number">3</span><span class="operator">,</span> availableGeometry<span class="operator">.</span>height() <span class="operator">/</span> <span class="number">2</span>); move((availableGeometry<span class="operator">.</span>width() <span class="operator">-</span> width()) <span class="operator">/</span> <span class="number">2</span><span class="operator">,</span> (availableGeometry<span class="operator">.</span>height() <span class="operator">-</span> height()) <span class="operator">/</span> <span class="number">2</span>); } <span class="keyword">else</span> { restoreGeometry(geometry); } } <span class="type">void</span> MainWindow<span class="operator">::</span>writeSettings() { <span class="type"><a href="../qtcore/qsettings.html">QSettings</a></span> settings(<span class="type"><a href="../qtcore/qcoreapplication.html">QCoreApplication</a></span><span class="operator">::</span>organizationName()<span class="operator">,</span> <span class="type"><a href="../qtcore/qcoreapplication.html">QCoreApplication</a></span><span class="operator">::</span>applicationName()); settings<span class="operator">.</span>setValue(<span class="string">"geometry"</span><span class="operator">,</span> saveGeometry()); } bool MainWindow<span class="operator">::</span>maybeSave() { <span class="keyword">if</span> (<span class="operator">!</span>textEdit<span class="operator">-</span><span class="operator">></span>document()<span class="operator">-</span><span class="operator">></span>isModified()) <span class="keyword">return</span> <span class="keyword">true</span>; <span class="keyword">const</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>StandardButton ret <span class="operator">=</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>warning(<span class="keyword">this</span><span class="operator">,</span> tr(<span class="string">"Application"</span>)<span class="operator">,</span> tr(<span class="string">"The document has been modified.\n"</span> <span class="string">"Do you want to save your changes?"</span>)<span class="operator">,</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Save <span class="operator">|</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Discard <span class="operator">|</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Cancel); <span class="keyword">switch</span> (ret) { <span class="keyword">case</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Save: <span class="keyword">return</span> save(); <span class="keyword">case</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Cancel: <span class="keyword">return</span> <span class="keyword">false</span>; <span class="keyword">default</span>: <span class="keyword">break</span>; } <span class="keyword">return</span> <span class="keyword">true</span>; } <span class="type">void</span> MainWindow<span class="operator">::</span>loadFile(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&</span>fileName) { <span class="type"><a href="../qtcore/qfile.html">QFile</a></span> file(fileName); <span class="keyword">if</span> (<span class="operator">!</span>file<span class="operator">.</span>open(<span class="type"><a href="../qtcore/qfile.html">QFile</a></span><span class="operator">::</span>ReadOnly <span class="operator">|</span> <span class="type"><a href="../qtcore/qfile.html">QFile</a></span><span class="operator">::</span>Text)) { <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>warning(<span class="keyword">this</span><span class="operator">,</span> tr(<span class="string">"Application"</span>)<span class="operator">,</span> tr(<span class="string">"Cannot read file %1:\n%2."</span>) <span class="operator">.</span>arg(<span class="type"><a href="../qtcore/qdir.html">QDir</a></span><span class="operator">::</span>toNativeSeparators(fileName)<span class="operator">,</span> file<span class="operator">.</span>errorString())); <span class="keyword">return</span>; } <span class="type"><a href="../qtcore/qtextstream.html">QTextStream</a></span> in(<span class="operator">&</span>file); <span class="preprocessor">#ifndef QT_NO_CURSOR</span> <span class="type"><a href="qapplication.html">QApplication</a></span><span class="operator">::</span>setOverrideCursor(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>WaitCursor); <span class="preprocessor">#endif</span> textEdit<span class="operator">-</span><span class="operator">></span>setPlainText(in<span class="operator">.</span>readAll()); <span class="preprocessor">#ifndef QT_NO_CURSOR</span> <span class="type"><a href="qapplication.html">QApplication</a></span><span class="operator">::</span>restoreOverrideCursor(); <span class="preprocessor">#endif</span> setCurrentFile(fileName); statusBar()<span class="operator">-</span><span class="operator">></span>showMessage(tr(<span class="string">"File loaded"</span>)<span class="operator">,</span> <span class="number">2000</span>); } bool MainWindow<span class="operator">::</span>saveFile(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&</span>fileName) { <span class="type"><a href="../qtcore/qfile.html">QFile</a></span> file(fileName); <span class="keyword">if</span> (<span class="operator">!</span>file<span class="operator">.</span>open(<span class="type"><a href="../qtcore/qfile.html">QFile</a></span><span class="operator">::</span>WriteOnly <span class="operator">|</span> <span class="type"><a href="../qtcore/qfile.html">QFile</a></span><span class="operator">::</span>Text)) { <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>warning(<span class="keyword">this</span><span class="operator">,</span> tr(<span class="string">"Application"</span>)<span class="operator">,</span> tr(<span class="string">"Cannot write file %1:\n%2."</span>) <span class="operator">.</span>arg(<span class="type"><a href="../qtcore/qdir.html">QDir</a></span><span class="operator">::</span>toNativeSeparators(fileName)<span class="operator">,</span> file<span class="operator">.</span>errorString())); <span class="keyword">return</span> <span class="keyword">false</span>; } <span class="type"><a href="../qtcore/qtextstream.html">QTextStream</a></span> out(<span class="operator">&</span>file); <span class="preprocessor">#ifndef QT_NO_CURSOR</span> <span class="type"><a href="qapplication.html">QApplication</a></span><span class="operator">::</span>setOverrideCursor(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>WaitCursor); <span class="preprocessor">#endif</span> out <span class="operator"><</span><span class="operator"><</span> textEdit<span class="operator">-</span><span class="operator">></span>toPlainText(); <span class="preprocessor">#ifndef QT_NO_CURSOR</span> <span class="type"><a href="qapplication.html">QApplication</a></span><span class="operator">::</span>restoreOverrideCursor(); <span class="preprocessor">#endif</span> setCurrentFile(fileName); statusBar()<span class="operator">-</span><span class="operator">></span>showMessage(tr(<span class="string">"File saved"</span>)<span class="operator">,</span> <span class="number">2000</span>); <span class="keyword">return</span> <span class="keyword">true</span>; } <span class="type">void</span> MainWindow<span class="operator">::</span>setCurrentFile(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&</span>fileName) { curFile <span class="operator">=</span> fileName; textEdit<span class="operator">-</span><span class="operator">></span>document()<span class="operator">-</span><span class="operator">></span>setModified(<span class="keyword">false</span>); setWindowModified(<span class="keyword">false</span>); <span class="type"><a href="../qtcore/qstring.html">QString</a></span> shownName <span class="operator">=</span> curFile; <span class="keyword">if</span> (curFile<span class="operator">.</span>isEmpty()) shownName <span class="operator">=</span> <span class="string">"untitled.txt"</span>; setWindowFilePath(shownName); } <span class="type"><a href="../qtcore/qstring.html">QString</a></span> MainWindow<span class="operator">::</span>strippedName(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&</span>fullFileName) { <span class="keyword">return</span> <span class="type"><a href="../qtcore/qfileinfo.html">QFileInfo</a></span>(fullFileName)<span class="operator">.</span>fileName(); } <span class="preprocessor">#ifndef QT_NO_SESSIONMANAGER</span> <span class="type">void</span> MainWindow<span class="operator">::</span>commitData(<span class="type"><a href="../qtgui/qsessionmanager.html">QSessionManager</a></span> <span class="operator">&</span>manager) { <span class="keyword">if</span> (manager<span class="operator">.</span>allowsInteraction()) { <span class="keyword">if</span> (<span class="operator">!</span>maybeSave()) manager<span class="operator">.</span>cancel(); } <span class="keyword">else</span> { <span class="comment">// Non-interactive: save without asking</span> <span class="keyword">if</span> (textEdit<span class="operator">-</span><span class="operator">></span>document()<span class="operator">-</span><span class="operator">></span>isModified()) save(); } } <span class="preprocessor">#endif</span> </pre> </div> <!-- @@@mainwindows/application/mainwindow.cpp --> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.<br/> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br/> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners. </p> </div> </body> </html>