Qt MDI window
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#ifndef MDICHILD_H
#define MDICHILD_H
#include <QTextEdit>
class MdiChild : public QTextEdit
{
Q_OBJECT
public:
MdiChild();
void newFile();
bool loadFile(const QString &fileName);
bool save();
bool saveAs();
bool saveFile(const QString &fileName);
QString userFriendlyCurrentFile();
QString currentFile() { return curFile; }
protected:
void closeEvent(QCloseEvent *event);
private slots:
void documentWasModified();
private:
bool maybeSave();
void setCurrentFile(const QString &fileName);
QString strippedName(const QString &fullFileName);
QString curFile;
bool isUntitled;
};
#endif
#include <QtGui>
#include "mdichild.h"
MdiChild::MdiChild()
{
setAttribute(Qt::WA_DeleteOnClose);
isUntitled = true;
}
void MdiChild::newFile()
{
static int sequenceNumber = 1;
isUntitled = true;
curFile = tr("document%1.txt").arg(sequenceNumber++);
setWindowTitle(curFile + "[*]");
connect(document(), SIGNAL(contentsChanged()),
this, SLOT(documentWasModified()));
}
bool MdiChild::loadFile(const QString &fileName)
{
QFile file(fileName);
if (!file.open(QFile::ReadOnly | QFile::Text)) {
QMessageBox::warning(this, tr("MDI"),
tr("Cannot read file %1:\n%2.")
.arg(fileName)
.arg(file.errorString()));
return false;
}
QTextStream in(&file);
QApplication::setOverrideCursor(Qt::WaitCursor);
setPlainText(in.readAll());
QApplication::restoreOverrideCursor();
setCurrentFile(fileName);
connect(document(), SIGNAL(contentsChanged()),
this, SLOT(documentWasModified()));
return true;
}
bool MdiChild::save()
{
if (isUntitled) {
return saveAs();
} else {
return saveFile(curFile);
}
}
bool MdiChild::saveAs()
{
QString fileName = QFileDialog::getSaveFileName(this, tr("Save As"),
curFile);
if (fileName.isEmpty())
return false;
return saveFile(fileName);
}
bool MdiChild::saveFile(const QString &fileName)
{
QFile file(fileName);
if (!file.open(QFile::WriteOnly | QFile::Text)) {
QMessageBox::warning(this, tr("MDI"),
tr("Cannot write file %1:\n%2.")
.arg(fileName)
.arg(file.errorString()));
return false;
}
QTextStream out(&file);
QApplication::setOverrideCursor(Qt::WaitCursor);
out << toPlainText();
QApplication::restoreOverrideCursor();
setCurrentFile(fileName);
return true;
}
QString MdiChild::userFriendlyCurrentFile()
{
return strippedName(curFile);
}
void MdiChild::closeEvent(QCloseEvent *event)
{
if (maybeSave()) {
event->accept();
} else {
event->ignore();
}
}
void MdiChild::documentWasModified()
{
setWindowModified(document()->isModified());
}
bool MdiChild::maybeSave()
{
if (document()->isModified()) {
QMessageBox::StandardButton ret;
ret = QMessageBox::warning(this, tr("MDI"),
tr("'%1' has been modified.\n"
"Do you want to save your changes?")
.arg(userFriendlyCurrentFile()),
QMessageBox::Save | QMessageBox::Discard
| QMessageBox::Cancel);
if (ret == QMessageBox::Save)
return save();
else if (ret == QMessageBox::Cancel)
return false;
}
return true;
}
void MdiChild::setCurrentFile(const QString &fileName)
{
curFile = QFileInfo(fileName).canonicalFilePath();
isUntitled = false;
document()->setModified(false);
setWindowModified(false);
setWindowTitle(userFriendlyCurrentFile() + "[*]");
}
QString MdiChild::strippedName(const QString &fullFileName)
{
return QFileInfo(fullFileName).fileName();
}
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
class MdiChild;
QT_BEGIN_NAMESPACE
class QAction;
class QMenu;
class QMdiArea;
class QMdiSubWindow;
class QSignalMapper;
QT_END_NAMESPACE
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow();
protected:
void closeEvent(QCloseEvent *event);
private slots:
void newFile();
void open();
void save();
void saveAs();
void cut();
void copy();
void paste();
void about();
void updateMenus();
void updateWindowMenu();
MdiChild *createMdiChild();
void switchLayoutDirection();
void setActiveSubWindow(QWidget *window);
private:
void createActions();
void createMenus();
void createToolBars();
void createStatusBar();
void readSettings();
void writeSettings();
MdiChild *activeMdiChild();
QMdiSubWindow *findMdiChild(const QString &fileName);
QMdiArea *mdiArea;
QSignalMapper *windowMapper;
QMenu *fileMenu;
QMenu *editMenu;
QMenu *windowMenu;
QMenu *helpMenu;
QToolBar *fileToolBar;
QToolBar *editToolBar;
QAction *newAct;
QAction *openAct;
QAction *saveAct;
QAction *saveAsAct;
QAction *exitAct;
QAction *cutAct;
QAction *copyAct;
QAction *pasteAct;
QAction *closeAct;
QAction *closeAllAct;
QAction *tileAct;
QAction *cascadeAct;
QAction *nextAct;
QAction *previousAct;
QAction *separatorAct;
QAction *aboutAct;
QAction *aboutQtAct;
};
#endif
#include <QtGui>
#include "mainwindow.h"
#include "mdichild.h"
MainWindow::MainWindow()
{
mdiArea = new QMdiArea;
mdiArea->setHorizontalScrollBarPolicy(Qt::ScrollBarAsNeeded);
mdiArea->setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded);
setCentralWidget(mdiArea);
connect(mdiArea, SIGNAL(subWindowActivated(QMdiSubWindow *)),
this, SLOT(updateMenus()));
windowMapper = new QSignalMapper(this);
connect(windowMapper, SIGNAL(mapped(QWidget *)),
this, SLOT(setActiveSubWindow(QWidget *)));
createActions();
createMenus();
createToolBars();
createStatusBar();
updateMenus();
readSettings();
setWindowTitle(tr("MDI"));
setUnifiedTitleAndToolBarOnMac(true);
}
void MainWindow::closeEvent(QCloseEvent *event)
{
mdiArea->closeAllSubWindows();
if (activeMdiChild()) {
event->ignore();
} else {
writeSettings();
event->accept();
}
}
void MainWindow::newFile()
{
MdiChild *child = createMdiChild();
child->newFile();
child->show();
}
void MainWindow::open()
{
QString fileName = QFileDialog::getOpenFileName(this);
if (!fileName.isEmpty()) {
QMdiSubWindow *existing = findMdiChild(fileName);
if (existing) {
mdiArea->setActiveSubWindow(existing);
return;
}
MdiChild *child = createMdiChild();
if (child->loadFile(fileName)) {
statusBar()->showMessage(tr("File loaded"), 2000);
child->show();
} else {
child->close();
}
}
}
void MainWindow::save()
{
if (activeMdiChild() && activeMdiChild()->save())
statusBar()->showMessage(tr("File saved"), 2000);
}
void MainWindow::saveAs()
{
if (activeMdiChild() && activeMdiChild()->saveAs())
statusBar()->showMessage(tr("File saved"), 2000);
}
void MainWindow::cut()
{
if (activeMdiChild())
activeMdiChild()->cut();
}
void MainWindow::copy()
{
if (activeMdiChild())
activeMdiChild()->copy();
}
void MainWindow::paste()
{
if (activeMdiChild())
activeMdiChild()->paste();
}
void MainWindow::about()
{
QMessageBox::about(this, tr("About MDI"),
tr("The <b>MDI</b> example demonstrates how to write multiple "
"document interface applications using Qt."));
}
void MainWindow::updateMenus()
{
bool hasMdiChild = (activeMdiChild() != 0);
saveAct->setEnabled(hasMdiChild);
saveAsAct->setEnabled(hasMdiChild);
pasteAct->setEnabled(hasMdiChild);
closeAct->setEnabled(hasMdiChild);
closeAllAct->setEnabled(hasMdiChild);
tileAct->setEnabled(hasMdiChild);
cascadeAct->setEnabled(hasMdiChild);
nextAct->setEnabled(hasMdiChild);
previousAct->setEnabled(hasMdiChild);
separatorAct->setVisible(hasMdiChild);
bool hasSelection = (activeMdiChild() &&
activeMdiChild()->textCursor().hasSelection());
cutAct->setEnabled(hasSelection);
copyAct->setEnabled(hasSelection);
}
void MainWindow::updateWindowMenu()
{
windowMenu->clear();
windowMenu->addAction(closeAct);
windowMenu->addAction(closeAllAct);
windowMenu->addSeparator();
windowMenu->addAction(tileAct);
windowMenu->addAction(cascadeAct);
windowMenu->addSeparator();
windowMenu->addAction(nextAct);
windowMenu->addAction(previousAct);
windowMenu->addAction(separatorAct);
QList<QMdiSubWindow *> windows = mdiArea->subWindowList();
separatorAct->setVisible(!windows.isEmpty());
for (int i = 0; i < windows.size(); ++i) {
MdiChild *child = qobject_cast<MdiChild *>(windows.at(i)->widget());
QString text;
if (i < 9) {
text = tr("&%1 %2").arg(i + 1)
.arg(child->userFriendlyCurrentFile());
} else {
text = tr("%1 %2").arg(i + 1)
.arg(child->userFriendlyCurrentFile());
}
QAction *action = windowMenu->addAction(text);
action->setCheckable(true);
action ->setChecked(child == activeMdiChild());
connect(action, SIGNAL(triggered()), windowMapper, SLOT(map()));
windowMapper->setMapping(action, windows.at(i));
}
}
MdiChild *MainWindow::createMdiChild()
{
MdiChild *child = new MdiChild;
mdiArea->addSubWindow(child);
connect(child, SIGNAL(copyAvailable(bool)),
cutAct, SLOT(setEnabled(bool)));
connect(child, SIGNAL(copyAvailable(bool)),
copyAct, SLOT(setEnabled(bool)));
return child;
}
void MainWindow::createActions()
{
newAct = new QAction(QIcon(":/images/new.png"), tr("&New"), this);
newAct->setShortcuts(QKeySequence::New);
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->setShortcuts(QKeySequence::Open);
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->setShortcuts(QKeySequence::Save);
saveAct->setStatusTip(tr("Save the document to disk"));
connect(saveAct, SIGNAL(triggered()), this, SLOT(save()));
saveAsAct = new QAction(tr("Save &As..."), this);
saveAsAct->setShortcuts(QKeySequence::SaveAs);
saveAsAct->setStatusTip(tr("Save the document under a new name"));
connect(saveAsAct, SIGNAL(triggered()), this, SLOT(saveAs()));
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->setShortcuts(QKeySequence::Cut);
cutAct->setStatusTip(tr("Cut the current selection's contents to the "
"clipboard"));
connect(cutAct, SIGNAL(triggered()), this, SLOT(cut()));
copyAct = new QAction(QIcon(":/images/copy.png"), tr("&Copy"), this);
copyAct->setShortcuts(QKeySequence::Copy);
copyAct->setStatusTip(tr("Copy the current selection's contents to the "
"clipboard"));
connect(copyAct, SIGNAL(triggered()), this, SLOT(copy()));
pasteAct = new QAction(QIcon(":/images/paste.png"), tr("&Paste"), this);
pasteAct->setShortcuts(QKeySequence::Paste);
pasteAct->setStatusTip(tr("Paste the clipboard's contents into the current "
"selection"));
connect(pasteAct, SIGNAL(triggered()), this, SLOT(paste()));
closeAct = new QAction(tr("Cl&ose"), this);
closeAct->setShortcut(tr("Ctrl+F4"));
closeAct->setStatusTip(tr("Close the active window"));
connect(closeAct, SIGNAL(triggered()),
mdiArea, SLOT(closeActiveSubWindow()));
closeAllAct = new QAction(tr("Close &All"), this);
closeAllAct->setStatusTip(tr("Close all the windows"));
connect(closeAllAct, SIGNAL(triggered()),
mdiArea, SLOT(closeAllSubWindows()));
tileAct = new QAction(tr("&Tile"), this);
tileAct->setStatusTip(tr("Tile the windows"));
connect(tileAct, SIGNAL(triggered()), mdiArea, SLOT(tileSubWindows()));
cascadeAct = new QAction(tr("&Cascade"), this);
cascadeAct->setStatusTip(tr("Cascade the windows"));
connect(cascadeAct, SIGNAL(triggered()), mdiArea, SLOT(cascadeSubWindows()));
nextAct = new QAction(tr("Ne&xt"), this);
nextAct->setShortcuts(QKeySequence::NextChild);
nextAct->setStatusTip(tr("Move the focus to the next window"));
connect(nextAct, SIGNAL(triggered()),
mdiArea, SLOT(activateNextSubWindow()));
previousAct = new QAction(tr("Pre&vious"), this);
previousAct->setShortcuts(QKeySequence::PreviousChild);
previousAct->setStatusTip(tr("Move the focus to the previous "
"window"));
connect(previousAct, SIGNAL(triggered()),
mdiArea, SLOT(activatePreviousSubWindow()));
separatorAct = new QAction(this);
separatorAct->setSeparator(true);
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()));
}
void MainWindow::createMenus()
{
fileMenu = menuBar()->addMenu(tr("&File"));
fileMenu->addAction(newAct);
fileMenu->addAction(openAct);
fileMenu->addAction(saveAct);
fileMenu->addAction(saveAsAct);
fileMenu->addSeparator();
QAction *action = fileMenu->addAction(tr("Switch layout direction"));
connect(action, SIGNAL(triggered()), this, SLOT(switchLayoutDirection()));
fileMenu->addAction(exitAct);
editMenu = menuBar()->addMenu(tr("&Edit"));
editMenu->addAction(cutAct);
editMenu->addAction(copyAct);
editMenu->addAction(pasteAct);
windowMenu = menuBar()->addMenu(tr("&Window"));
updateWindowMenu();
connect(windowMenu, SIGNAL(aboutToShow()), this, SLOT(updateWindowMenu()));
menuBar()->addSeparator();
helpMenu = menuBar()->addMenu(tr("&Help"));
helpMenu->addAction(aboutAct);
helpMenu->addAction(aboutQtAct);
}
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);
}
void MainWindow::createStatusBar()
{
statusBar()->showMessage(tr("Ready"));
}
void MainWindow::readSettings()
{
QSettings settings("Trolltech", "MDI Example");
QPoint pos = settings.value("pos", QPoint(200, 200)).toPoint();
QSize size = settings.value("size", QSize(400, 400)).toSize();
move(pos);
resize(size);
}
void MainWindow::writeSettings()
{
QSettings settings("Trolltech", "MDI Example");
settings.setValue("pos", pos());
settings.setValue("size", size());
}
MdiChild *MainWindow::activeMdiChild()
{
if (QMdiSubWindow *activeSubWindow = mdiArea->activeSubWindow())
return qobject_cast<MdiChild *>(activeSubWindow->widget());
return 0;
}
QMdiSubWindow *MainWindow::findMdiChild(const QString &fileName)
{
QString canonicalFilePath = QFileInfo(fileName).canonicalFilePath();
foreach (QMdiSubWindow *window, mdiArea->subWindowList()) {
MdiChild *mdiChild = qobject_cast<MdiChild *>(window->widget());
if (mdiChild->currentFile() == canonicalFilePath)
return window;
}
return 0;
}
void MainWindow::switchLayoutDirection()
{
if (layoutDirection() == Qt::LeftToRight)
qApp->setLayoutDirection(Qt::RightToLeft);
else
qApp->setLayoutDirection(Qt::LeftToRight);
}
void MainWindow::setActiveSubWindow(QWidget *window)
{
if (!window)
return;
mdiArea->setActiveSubWindow(qobject_cast<QMdiSubWindow *>(window));
}
#include <QApplication>
#include "mainwindow.h"
int main(int argc, char *argv[])
{
Q_INIT_RESOURCE(mdi);
QApplication app(argc, argv);
MainWindow mainWin;
mainWin.show();
return app.exec();
}
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