Qt: 内建对话框（各种对话框都有了，且用到了qobject_cast解析sender的技术）

#include "BuiltinDialog.h"

#include <QtGui/QTextEdit>

#include <QtGui/QPushButton>

#include <QtGui/QFileDialog>

#include <QtGui/QFontDialog>

#include <QtGui/QColorDialog>

#include <QtGui/QPrintDialog>

#include <QtGui/QInputDialog>

#include <QtGui/QErrorMessage>

#include <QtGui/QProgressDialog>

#include <QtGui/QPageSetupDialog>

#include <QtGui/QGridLayout>

#include <QtGui/QPalette>

#include <QtGui/QColor>

#include <QtGui/QPrinter>

#include <QtGui/QApplication>

#include <QtDebug>

BuiltinDialog::BuiltinDialog(QWidget *parent) :

QDialog(parent) {

// Create widgets.

displayTextEdit = new QTextEdit();

showFileDialogButton = new QPushButton(QObject::tr("File Dialog"));

showFontDialogButton = new QPushButton(QObject::tr("Font Dialog"));

showColorDialogButton = new QPushButton(QObject::tr("Color Dialog"));

showPrintDialogButton = new QPushButton(QObject::tr("Print Dialog"));

showInputDialogButton = new QPushButton(QObject::tr("Input Dialog"));

showErrorDialogButton = new QPushButton(QObject::tr("Error Dialog"));

showProgressDialogButton = new QPushButton(QObject::tr("Progress Dialog"));

showPageSetupDialogButton = new QPushButton(

QObject::tr("Page Setup Dialog"));

// Lay out widgets.

QGridLayout *gridLayout = new QGridLayout();

gridLayout->addWidget(showFileDialogButton, 0, 0, 1, 1);

gridLayout->addWidget(showFontDialogButton, 0, 1, 1, 1);

gridLayout->addWidget(showColorDialogButton, 0, 2, 1, 1);

gridLayout->addWidget(showPrintDialogButton, 1, 0, 1, 1);

gridLayout->addWidget(showInputDialogButton, 1, 1, 1, 1);

gridLayout->addWidget(showErrorDialogButton, 1, 2, 1, 1);

gridLayout->addWidget(showProgressDialogButton, 2, 0, 1, 1);

gridLayout->addWidget(showPageSetupDialogButton, 2, 1, 1, 1);

gridLayout->addWidget(displayTextEdit, 3, 0, 3, 3);

setLayout(gridLayout);

// Connect signals and slots.

QObject::connect(showFileDialogButton, SIGNAL(clicked()), this, SLOT(

buttonsClicked()));

QObject::connect(showFontDialogButton, SIGNAL(clicked()), this, SLOT(

buttonsClicked()));

QObject::connect(showColorDialogButton, SIGNAL(clicked()), this, SLOT(

buttonsClicked()));

QObject::connect(showPrintDialogButton, SIGNAL(clicked()), this, SLOT(

buttonsClicked()));

QObject::connect(showInputDialogButton, SIGNAL(clicked()), this, SLOT(

buttonsClicked()));

QObject::connect(showErrorDialogButton, SIGNAL(clicked()), this, SLOT(

buttonsClicked()));

QObject::connect(showProgressDialogButton, SIGNAL(clicked()), this, SLOT(

buttonsClicked()));

QObject::connect(showPageSetupDialogButton, SIGNAL(clicked()), this, SLOT(

buttonsClicked()));

// Initialize.

setWindowTitle(QObject::tr("Builtin Dialogs"));

}

void BuiltinDialog::buttonsClicked() {

QPushButton *button = qobject_cast<QPushButton *> (sender());

if (button == showFileDialogButton) {

QString fileName = QFileDialog::getOpenFileName(this, QObject::tr(

"Open File"), QDir::home().path(), QObject::tr(

"Images(*.png *.jpg *.gif)"));

displayTextEdit->setText(fileName);

} else if (button == showFontDialogButton) {

bool ok;

const QFont &font = QFontDialog::getFont(&ok, displayTextEdit->font(),

this);

if (ok) {

displayTextEdit->setFont(font);

}

} else if (button == showColorDialogButton) {

QPalette palette = displayTextEdit->palette();

const QColor &color = QColorDialog::getColor(palette.color(

QPalette::Base), this);

if (color.isValid()) {

palette.setColor(QPalette::Base, color);

displayTextEdit->setPalette(palette);

}

} else if (button == showPrintDialogButton) {

QPrinter printer;

QPrintDialog dialog(&printer, this);

dialog.setWindowTitle(QObject::tr("Print Dialog"));

if (QDialog::Accepted == dialog.exec()) {

displayTextEdit->setText("Printing file.....");

}

} else if (button == showInputDialogButton) {

bool ok;

QString text = QInputDialog::getText(this, QObject::tr(

"Input User Name"), QObject::tr("User Name: "),

QLineEdit::Normal, QDir::home().dirName(), &ok);

if (ok && !text.isEmpty()) {

displayTextEdit->setText(text);

}

} else if (button == showErrorDialogButton) {

QErrorMessage box(this);

box.setWindowTitle(QObject::tr("Error Message"));

box.showMessage(QObject::tr("There are errors XX."));

box.showMessage(QObject::tr("There are errors XX."));

box.showMessage(QObject::tr("There are errors XX."));

box.showMessage(QObject::tr("There are errors YY."));

box.exec();

} else if (button == showProgressDialogButton) {

int maxValue = 10000;

QProgressDialog dialog(QObject::tr("Copying files..."), QObject::tr(

"Cancel"), 0, maxValue, this);

dialog.setWindowModality(Qt::WindowModal);

dialog.setWindowTitle(QObject::tr("Progress Dialog"));

dialog.show();

for (int i = 0; i < maxValue; ++i) {

dialog.setValue(i);

qApp->processEvents();

if (dialog.wasCanceled()) {

break;

}

qDebug() << i; // #include <QtDebug>

}

dialog.setValue(maxValue);

} else if (button == showPageSetupDialogButton) {

QPrinter printer;

QPageSetupDialog dlg(&printer, this);

dlg.setWindowTitle(QObject::tr("Page Setup"));

if (QDialog::Accepted == dlg.exec()) {

displayTextEdit->setText("Page's properties are setupped.");

}

}

}

http://www.cppblog.com/biao/archive/2009/03/28/78105.html