source: trunk/doc/src/snippets/code/doc_src_qt4-intro.qdoc@ 846

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//! [0]
QT -= gui
//! [0]


//! [1]
QT += network opengl sql qt3support
//! [1]


//! [2]
CONFIG += uic3
//! [2]


//! [3]
#include <QClassName>
//! [3]


//! [4]
#include <QString>
#include <QApplication>
#include <QSqlTableModel>
//! [4]


//! [5]
#include <qclassname.h>
//! [5]


//! [6]
#include <QtCore>
//! [6]


//! [7]
using namespace Qt;
//! [7]


//! [8]
QLabel *label1 = new QLabel("Hello", this);
QLabel *label2 = new QLabel(this, "Hello");
//! [8]


//! [9]
MyWidget::MyWidget(QWidget *parent, const char *name)
    : QWidget(parent, name)
{
    ...
}
//! [9]


//! [10]
// DEPRECATED
if (obj->inherits("QPushButton")) {
    QPushButton *pushButton = (QPushButton *)obj;
    ...
}
//! [10]


//! [11]
QPushButton *pushButton = qobject_cast<QPushButton *>(obj);
if (pushButton) {
    ...
}
//! [11]


//! [12]
QLabel *label = new QLabel;
QPointer<QLabel> safeLabel = label;
safeLabel->setText("Hello world!");
delete label;
// safeLabel is now 0, whereas label is a dangling pointer
//! [12]


//! [13]
QT += qt3support
//! [13]


//! [14]
DEFINES += QT3_SUPPORT
//! [14]


//! [15]
DEFINES += QT3_SUPPORT_WARNINGS
//! [15]


//! [16]
DEFINES += QT3_SUPPORT
//! [16]