SDI Application



áÇÍÙ Åä Çá Application ÚÈÇÑÉ Úä
1 – Main Window
2 – MenuBar ÈÊÔãá File, Edit, Help menus
3- ToolBar 2
ÇáÃæá åæ fileToolBar æÝíå new, open and save
ÇáÊÇäì åæ editToolBar æÝíå cut, copy and paste

4- TextEdit
5- StatusBar


åäÍÊÇÌ äÚãá 3 ãáÝÇÊ áá Application
1- mainwindow.h Ýíå Çá class design
2- mainwindow.cpp Ýíå Çá class implementation
3- main.cpp Ýíå Çá entry point áá Application

mainwindow.h

ÈÏÇíÉ ÞÈá Çì ÔÆ

#ifndef MAINWINDOW_H
 #define MAINWINDOW_H

åäÍÊÇÌ äÚãá include á QMainWindow
#include <QMainWindow>
ÚÔÇä äæÑËåÇ áá mainwindow class

class MainWindow : public QMainWindow

áÇÍÙ ÅääÇ Òì ãÇÞáäÇ åäÓÊÎÏã menu, toolbar, actions

class QAction;
 class QMenu;
 class QTextEdit;

ãáÍæÙÉ Çá actions åì ÇáÚäÇÕÑ Çááì ÈÊßæä Çá menus æÇá toolbars !

åäÚãá Ýì Çá class ÏÇ Override áá virtual closeEvent method æåì method ÈÊ fired ßá ãíÍÕá ãÍÇæáÉ á ÞÝá Çá window ÝÅÍäÇ åäÚãá áíåÇ new definition ÚÔÇä äÓÊÎÏã Çá
famous message “you wanna quit !? “

Çá class åíßæä áíå slots ÎÇÕÉ Ýíå íÈÞÉ áÇÒã äÚÑÝ Çámacro Q_OBJECT!

Çá slots åÊßæä Åíå ¿
newFile, save, saveAs, about, documentWasModified
Çá newFile åäÓÊÎÏãåÇ ÚÔÇä äÈÏà Ýì new file
Çá save/save as ÚÔÇä äÍÝÙ ÇáãáÝ Èíåã
Çá about åäÓÊÎÏãåÇ ÚÔÇä äÙåÑ window ÈÊÊßáã Úä ÇáÈÑäÇãÌ æåäÇß åäÓÊÎÏã qtabout ÇáãæÌæÏÉ Ýì Qapplication!
Çá documentWasModified ÚÔÇä ÊÔíÑ åá ÇáãáÝ ÇÊÚÏá Ýíå æáÇ áà ÚÔÇä äÓÊÎÏã save or not MSG

äÏÎá Ýì ãíËæÏÒ Çá class äÝÓåÇ ÈÞÉ

1- init()
2- createActions()
3- createMenus()
4- createToolBars()
5- createStatusBar()
6- bool maybeSave()
7- loadFile()
8- bool saveFile()
9- setCurrentFile()
10- QString strippedName()
11- QMainWindow findMainWindow()

ÇÍäÇ ããßä äÎáì Çá GUI Ýì Çá Constructor ÈÓ ÇáãÔßáÉ ÇáæÍíÏÉ åì ÅääÇ ÚäÏäÇ 2 Constructors ÝãÔ ÚÇíÒíä äßÑÑ äÝÓäÇ ÝäÚãá ãíËæÏ áá init window
strippedName ÈÊÑÌÚ áíäÇ ÇÓã ÇáÝíá ÈÏæä Çá full name


Çá fields

QTextEdit *textEdit;
         QString curFile;
         bool isUntitled;
         QMenu *fileMenu;
         QMenu *editMenu;
         QMenu *helpMenu;
         QToolBar *fileToolBar;
         QToolBar *editToolBar;
         QAction *newAct;
         QAction *openAct;
         QAction *saveAct;
         QAction *saveAsAct;
         QAction *closeAct;
         QAction *exitAct;
         QAction *cutAct;
         QAction *copyAct;
         QAction *pasteAct;
         QAction *aboutAct;
         QAction *aboutQtAct

;
æåì ÚÈÇÑÉ Úä ÇáActions/Menus/ToolBars
isUntitled áÊÔíÑ åá ÇáãáÝ áÓå Çæá ãÑÉ æãÔ ÇÊÍÝÙ ÈÅÓã æáÇ áÃ
curFile áÊÔíÑ ááãáÝ ÇáÍÇáì
æÈßÏÇ íÈÞÉ ÎáÕ Çá header
ÇáÕæÑÉ ÇáäåÇÆíÉ áíå

#ifndef MAINWINDOW_H
 #define MAINWINDOW_H
 #include <QMainWindow>
 class QAction;
 class QMenu;
 class QTextEdit;
 class MainWindow : public QMainWindow
 {
         Q_OBJECT
 public:
         MainWindow();
         MainWindow(const QString &fileName);
 protected:
         void closeEvent(QCloseEvent *event);
 private slots:
         void newFile();
         void open();
         bool save();
         bool saveAs();
         void about();
         void documentWasModified();
 private:
         void init();
         void createActions();
         void createMenus();
         void createToolBars();
         void createStatusBar();
         void readSettings();
         void writeSettings();
         bool maybeSave();
         void loadFile(const QString &fileName);
         bool saveFile(const QString &fileName);
         void setCurrentFile(const QString &fileName);
         QString strippedName(const QString &fullFileName);
         MainWindow *findMainWindow(const QString &fileName);
         QTextEdit *textEdit;
         QString curFile;
         bool isUntitled;
         QMenu *fileMenu;
         QMenu *editMenu;
         QMenu *helpMenu;
         QToolBar *fileToolBar;
         QToolBar *editToolBar;
         QAction *newAct;
         QAction *openAct;
         QAction *saveAct;
         QAction *saveAsAct;
         QAction *closeAct;
         QAction *exitAct;
         QAction *cutAct;
         QAction *copyAct;
         QAction *pasteAct;
         QAction *aboutAct;
         QAction *aboutQtAct;
 };
 #endif

áÇÍÙ Çá images Çááì Ýì Çá Application åäÓÊÎÏãåÇ Úä ØÑíÞ Çá resource file

<!DOCTYPE RCC><RCC version="1.0">
 <qresource>
         <file>images/copy.png</file>
         <file>images/cut.png</file>
         <file>images/new.png</file>
         <file>images/open.png</file>
         <file>images/paste.png</file>
         <file>images/save.png</file>
 </qresource>
 </RCC>

äÏÎá Ýì Çá implementation
åäÍÊÇÌ äÓÊÎÏã QtGui ÚÔÇä Çá widgets æÇá windows æåäÍÊÇÌ äÚãá include áá mainwindow.h

#include <QtGui>
#include "mainwindow.h"

Çá init method æåì ÊÚÊÈÑ Çá entry point Çááì åíÊã ÝíåÇ ÇáÊÕãíã áá gui æÊÌåíÒ Çá window
v

oid MainWindow::init()
 {
         setAttribute(Qt::WA_DeleteOnClose);
         isUntitled = true;
         textEdit = new QTextEdit;
         setCentralWidget(textEdit);
         createActions();
         createMenus();
         createToolBars();
         createStatusBar();
         readSettings();
         connect(textEdit->document(), SIGNAL(contentsChanged()),
                         this, SLOT(documentWasModified()));
 }

ãäØÞì Åä áãÇ ÊÈÏà ÇáÈÑäÇãÌ åíßæä Çá file ÇáÍÇáì ãÔ áíå ÅÓã ÝåäÎáì Çá isUntitle ÞíãÊåÇ true
äÚãá QtextEdit Object æäÎáíå Ýì ÓäÊÑ ÇáæíäÏæ áÃä ÝæÞå Çá menu/toolbars æÊÍÊå Çá statusbar
createActions æ createMenus æ createToolsBars æ createStatusBar ÈÊäÔÆ áíäÇ Çá Actions/Menus/Toolbars/StatusBar

Çá Actions

void MainWindow::createActions()
 {
         newAct = new QAction(QIcon(":/images/new.png"), tr("&New"), this);
         newAct->setShortcut(tr("Ctrl+N"));
         newAct->setStatusTip(tr("Create a new file"));
         connect(newAct, SIGNAL(triggered()), this, SLOT(newFile()));
         openAct = new QAction(QIcon(":/images/open.png"), tr("&Open..."), this);
         openAct->setShortcut(tr("Ctrl+O"));
         openAct->setStatusTip(tr("Open an existing file"));
         connect(openAct, SIGNAL(triggered()), this, SLOT(open()));
         saveAct = new QAction(QIcon(":/images/save.png"), tr("&Save"), this);
         saveAct->setShortcut(tr("Ctrl+S"));
         saveAct->setStatusTip(tr("Save the document to disk"));
         connect(saveAct, SIGNAL(triggered()), this, SLOT(save()));
         saveAsAct = new QAction(tr("Save &As..."), this);
         saveAsAct->setStatusTip(tr("Save the document under a new name"));
         connect(saveAsAct, SIGNAL(triggered()), this, SLOT(saveAs()));
         closeAct = new QAction(tr("&Close"), this);
         closeAct->setShortcut(tr("Ctrl+W"));
         closeAct->setStatusTip(tr("Close this window"));
         connect(closeAct, SIGNAL(triggered()), this, SLOT(close()));
         exitAct = new QAction(tr("E&xit"), this);
         exitAct->setShortcut(tr("Ctrl+Q"));
         exitAct->setStatusTip(tr("Exit the application"));
         connect(exitAct, SIGNAL(triggered()), qApp, SLOT(closeAllWindows()));
         cutAct = new QAction(QIcon(":/images/cut.png"), tr("Cu&t"), this);
         cutAct->setShortcut(tr("Ctrl+X"));
         cutAct->setStatusTip(tr("Cut the current selection's contents to the "
                                                         "clipboard"));
         connect(cutAct, SIGNAL(triggered()), textEdit, SLOT(cut()));
         copyAct = new QAction(QIcon(":/images/copy.png"), tr("&Copy"), this);
         copyAct->setShortcut(tr("Ctrl+C"));
         copyAct->setStatusTip(tr("Copy the current selection's contents to the "
                                                          "clipboard"));
         connect(copyAct, SIGNAL(triggered()), textEdit, SLOT(copy()));
         pasteAct = new QAction(QIcon(":/images/paste.png"), tr("&Paste"), this);
         pasteAct->setShortcut(tr("Ctrl+V"));
         pasteAct->setStatusTip(tr("Paste the clipboard's contents into the current "
                                                           "selection"));
         connect(pasteAct, SIGNAL(triggered()), textEdit, SLOT(paste()));
         aboutAct = new QAction(tr("&About"), this);
         aboutAct->setStatusTip(tr("Show the application's About box"));
         connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));
         aboutQtAct = new QAction(tr("About &Qt"), this);
         aboutQtAct->setStatusTip(tr("Show the Qt library's About box"));
         connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));
         cutAct->setEnabled(false);
         copyAct->setEnabled(false);
         connect(textEdit, SIGNAL(copyAvailable(bool)),
                         cutAct, SLOT(setEnabled(bool)));
         connect(textEdit, SIGNAL(copyAvailable(bool)),
                         copyAct, SLOT(setEnabled(bool)));
 }

åÔÑÍ Çá newAction ÈÓ æÇáÈÇÞì äÝÓ ÇáÝßÑÉ

newAct = new QAction(QIcon(":/images/new.png"), tr("&New"), this);
         newAct->setShortcut(tr("Ctrl+N"));
         newAct->setStatusTip(tr("Create a new file"));
         connect(newAct, SIGNAL(triggered()), this, SLOT(newFile()));

Çá Qaction Constructor ÈíÇÎÏ 3 parameters Çá Ãæá áíÔíÑ áá Icon Çááì Ýì ÇáAction æÇáÊÇäì ÈíÔíÑ áá Text ÇáÙÇåÑ Úáì Çá Action æÇáÊÇáÊ ÈíÔíÑ áá current ref æåæ this
setStatusTip æåì Çá text Çááì åíÙåÑ Ýì Çá statusBar ßá ãÇÊãÑ Úáì Çánew Action
äÑÈØ Çá triggered SIGNAL ãÚ Çá newFile SLOT È Connect æÇásender åäÇ åíßæä newAction æÇá receiver åíßæä Çá main window
áÇÍÙ

        aboutQtAct = new QAction(tr("About &Qt"), this);
         aboutQtAct->setStatusTip(tr("Show the Qt library's About box"));
         connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));

Ýì Çá Connect åäÇ Çá sender åæ aboutQtAction æÇá receiver åæ Çá qApp æåæ ÈíÞÏã slot ÈÅÓã aboutQt ÈÊÙåÑ Çá about window ÇáÅÝÊÑÇÖíÉ

Çá Copy/Cut/Paste stuff ÇäÊ ãÔ áíß ÏÚæÉ Èíåã ßá Çááì Úáíß ÊÑÈØ Çá Action ÈÇá textEdit æÊÓÊÎÏã Çá slot ÇáãäÇÓÈÉ ÓæÇÁ copy, cut or paste
Keep it simple !
Çá setEnabled ÇÚÊÞÏ æÇÖÍÉ æåì Åäß ÊÞÏÑ Ê trigger Çá Action Çæ áà æÈÊÇÎÏ true/false

void MainWindow::about()
 {
        QMessageBox::about(this, tr("About SDI"),
                         tr("The <b>SDI</b> example demonstrates how to write single "
                                "document interface applications using Qt."));
 }

ÈãÌÑÏ ÖÛØß Úáì Çá about action åíÙåÑ messagebox áÇÍÙ Åäß ÊÞÏÑ ÊÓÊÎÏã HTML tag

ÅäÔÇÁ Çá menus

void MainWindow::createMenus()
 {
         fileMenu = menuBar()->addMenu(tr("&File"));
         fileMenu->addAction(newAct);
         fileMenu->addAction(openAct);
         fileMenu->addAction(saveAct);
         fileMenu->addAction(saveAsAct);
         fileMenu->addSeparator();
         fileMenu->addAction(closeAct);
         fileMenu->addAction(exitAct);
         editMenu = menuBar()->addMenu(tr("&Edit"));
         editMenu->addAction(cutAct);
         editMenu->addAction(copyAct);
         editMenu->addAction(pasteAct);
         menuBar()->addSeparator();
         helpMenu = menuBar()->addMenu(tr("&Help"));
         helpMenu->addAction(aboutAct);
         helpMenu->addAction(aboutQtAct);
 }

ßá Çááì Úáíß Åäß ÊÓÊÎÏã addMenu method æÊÈÇÕì áíåÇ ÅÓã Çá Menu Çááì åÊÈÞÉ ãæÌæÏÉ Ýì Çá MenuBar
æÝì ßá menu ÚãáÊåÇ ÊÖíÝ Çá Actions ÇáÎÇÕÉ ÈíåÇ ÈÅÓÊÎÏÇã addAction æáÊÖíÝ separator ÅÓÊÎÏÇã addSeparator method
Úãá Çá ToolBars ÈÓíØ ÌÏÇ

void MainWindow::createToolBars()
 {
         fileToolBar = addToolBar(tr("File"));
         fileToolBar->addAction(newAct);
         fileToolBar->addAction(openAct);
         fileToolBar->addAction(saveAct);
         editToolBar = addToolBar(tr("Edit"));
         editToolBar->addAction(cutAct);
         editToolBar->addAction(copyAct);
         editToolBar->addAction(pasteAct);

}

createStatusBar

void MainWindow::createStatusBar()
 {
         statusBar()->showMessage(tr("Ready"));
 }

maybeSave ÚÔÇä äåÏá save or not

bool MainWindow::maybeSave()
 {
         if (textEdit->document()->isModified()) {
                 QMessageBox::StandardButton ret;
                 ret = QMessageBox::warning(this, tr("SDI"),
                                          tr("The document has been modified.\n"
                                                 "Do you want to save your changes?"),
                                          QMessageBox::Save | QMessageBox::Discard
                                          | QMessageBox::Cancel);
                 if (ret == QMessageBox::Save)
                         return save();
                 else if (ret == QMessageBox::Cancel)
                         return false;
         }
         return true;
 }

æÈäÇÁ Úáì Çá response åäÔæÝ åäÓÊÎÏã åäÓÊÎÏã Çì ÑÏ ÝÚá
loadFile

void MainWindow::loadFile(const QString &fileName)
 {
         QFile file(fileName);
         if (!file.open(QFile::ReadOnly | QFile::Text)) {
                 QMessageBox::warning(this, tr("SDI"),
                                                          tr("Cannot read file %1:\n%2.")
                                                          .arg(fileName)
                                                          .arg(file.errorString()));
                 return;
         }
         QTextStream in(&file);
         QApplication::setOverrideCursor(Qt::WaitCursor);
         textEdit->setPlainText(in.readAll());
         QApplication::restoreOverrideCursor();
         setCurrentFile(fileName);
         statusBar()->showMessage(tr("File loaded"), 2000);
 }

ßá ÇáÝßÑÉ åì Úãá Qfile Object æäÎÊÈÑ åá ÇáãáÝ readOnly Çæ áà Ýì ÍÇá Åäå ãÊæÇÝÞ ãÚÇäÇ åäÚãá QtextStream object æäÈÇÕì ßá Çááì Ýíå -readAll method- á Çá setPlainText ÇáÎÇÕÉ È textEdit
áÇÍÙ ãæÖæÚ Çá Qt::WaitCursor ÚÔÇä äÎáì Çácursor ÈÇíä Åä Ýì ÈÑæÓÓ ÔÛÇáÉ
Çá restoreOverrideCursor ÈäÓÊÚíÏ Çácursor ÈÕæÑÊå ÇáÓÇÈÞÉ.
äÎáì ÅÓã Çá currentFile åæ ÅÓã Çá Opened File ÈÅÓÊÎÏÇã setCurrentFile æäÔíÑ Ýì Çá statusBar Çä Çá File Loaded ÈÅÓÊÎÏÇã Çá showMessage.

QString MainWindow::strippedName(const QString &fullFileName)
 {
         return QFileInfo(fullFileName).fileName();
 }

ááÍÕæá Úáì ÇÓã Çá File ÝÞØ äÓÊÎÏã fileName method ÊÍÊ Çá QfileInfo æåì ÈÊÏì return á Qstring ÈÇáÅÓã ÇáãÎÊÕÑ áá File


setCurrentFile

void MainWindow::setCurrentFile(const QString &fileName)
 {
         static int sequenceNumber = 1;
         isUntitled = fileName.isEmpty();
         if (isUntitled) {
                 curFile = tr("document%1.txt").arg(sequenceNumber++);
         } else {
                 curFile = QFileInfo(fileName).canonicalFilePath();
         }
         textEdit->document()->setModified(false);
         setWindowModified(false);
         setWindowTitle(tr("%1[*] - %2").arg(strippedName(curFile))
                                                                                .arg(tr("SDI")));
 }

Úãá Save áá File

bool MainWindow::saveFile(const QString &fileName)
 {
         QFile file(fileName);
         if (!file.open(QFile::WriteOnly | QFile::Text)) {
                 QMessageBox::warning(this, tr("SDI"),
                                                          tr("Cannot write file %1:\n%2.")
                                                          .arg(fileName)
                                                          .arg(file.errorString()));
                 return false;
         }
         QTextStream out(&file);
         QApplication::setOverrideCursor(Qt::WaitCursor);
         out << textEdit->toPlainText();
         QApplication::restoreOverrideCursor();
         setCurrentFile(fileName);
         statusBar()->showMessage(tr("File saved"), 2000);
         return true;
 }

Save/Save As

bool MainWindow::save()
 {
         if (isUntitled) {
                 return saveAs();
         } else {
                 return saveFile(curFile);
         }

}

 bool MainWindow::saveAs()
 {
         QString fileName = QFileDialog::getSaveFileName(this, tr("Save As"),
                                                                                                         curFile);
         if (fileName.isEmpty())
                 return false;
         return saveFile(fileName);
 }

Ýì ÍÇá áæ Çá currentFile áíå ÇÓã íÚäì isUntitled åÊÏì false åíÊã ÅÓÊÏÚÇÁ saveFile method
Ýì ÍÇá áæ ãÔ áíå ÅÓã Çæ isUntitled åÊÏì true åíÊã ÅÓÊÏÚÇÁ saveAs method æåì åÊÍÝÙ Çá file È save file dialog áØíÝ ááãÓÊÎÏã


ÈÇáãäÇÓÈÉ Ýì ÍÇáÉ Çá newFileAction åíÊÚãá Object ÌÏíÏ ãä Çá mainwindow æåßÐÇ Úáì ÈÚÏ 40 æ 40 ãä Çá x, y Çááì ÈÇÏÆ Úäåã Çá window

 void MainWindow::newFile()
 {
         MainWindow *other = new MainWindow;
         other->move(x() + 40, y() + 40);
         other->show();
 }

æÇÎíÑÇ Çá main.cpp æåæ Çá Entry point ááÈÑäÇãÌ

 #include <QApplication>

 #include "mainwindow.h"

 int main(int argc, char *argv[])
 {
         Q_INIT_RESOURCE(sdi);
         QApplication app(argc, argv);
         MainWindow *mainWin = new MainWindow;
         mainWin->show();
         return app.exec();
 }

Q_INIT_RESOURCE ÈäÈÇÕì áíåÇ ÅÓã ãáÝ Çá resource ÇáãÓÊÎÏã
ßÝÇíÉ ßáÇã áÍÏ ßÏÇ ÈÇÞì ÇáÓæÑÓ ÈÓíØ
ÇáãÑÉ ÇáÌÇíÉ äÈÞÉ äÚãá MDI Application

Çá source ãä Çá QT Examples Ýì mainwindow/sdi