qt-everywhere-src-5.14.1/qtbase/examples/widgets/doc/src/classwizard.qdoc

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/*!
    \example dialogs/classwizard
    \title Class Wizard Example
    \ingroup examples-dialogs

    \brief The Class Wizard example shows how to implement linear
    wizards using QWizard.

    \image classwizard.png Screenshot of the Class Wizard example

    Most wizards have a linear structure, with page 1 followed by
    page 2 and so on until the last page. Some wizards are more
    complex in that they allow different traversal paths based on the
    information provided by the user. The
    \l{dialogs/licensewizard}{License Wizard} example shows how to
    create such wizards.

    The Class Wizard example consists of the following classes:

    \list
    \li \c ClassWizard inherits QWizard and provides a
       three-step wizard that generates the skeleton of a C++ class
       based on the user's input.
    \li \c IntroPage, \c ClassInfoPage, \c CodeStylePage, \c
       OutputFilesPage, and \c ConclusionPage are QWizardPage
       subclasses that implement the wizard pages.
    \endlist

    \section1 ClassWizard Class Definition

    \image classwizard-flow.png The Class Wizard pages

    We will see how to subclass QWizard to implement our own wizard.
    The concrete wizard class is called \c ClassWizard and provides
    five pages:

    \list
    \li The first page is an introduction page, telling the user what
       the wizard is going to do.
    \li The second page asks for a class name and a base class, and
       allows the user to specify whether the class should have a \c
       Q_OBJECT macro and what constructors it should provide.
    \li The third page allows the user to set some options related to the code
       style, such as the macro used to protect the header file from
       multiple inclusion (e.g., \c MYDIALOG_H).
    \li The fourth page allows the user to specify the names of the
       output files.
    \li The fifth page is a conclusion page.
    \endlist

    Although the program is just an example, if you press \uicontrol Finish
    (\uicontrol Done on \macos), actual C++ source files will actually be
    generated.

    \section1 The ClassWizard Class

    Here's the \c ClassWizard definition:

    \snippet dialogs/classwizard/classwizard.h 0

    The class reimplements QDialog's \l{QDialog::}{accept()} slot.
    This slot is called when the user clicks \uicontrol{Finish}.

    Here's the constructor:

    \snippet dialogs/classwizard/classwizard.cpp 1

    We instantiate the five pages and insert them into the wizard
    using QWizard::addPage(). The order in which they are inserted
    is also the order in which they will be shown later on.

    We call QWizard::setPixmap() to set the banner and the
    background pixmaps for all pages. The banner is used as a
    background for the page header when the wizard's style is
    \l{QWizard::}{ModernStyle}; the background is used as the
    dialog's background in \l{QWizard::}{MacStyle}. (See \l{Elements
    of a Wizard Page} for more information.)

    \snippet dialogs/classwizard/classwizard.cpp 3
    \snippet dialogs/classwizard/classwizard.cpp 4
    \dots
    \snippet dialogs/classwizard/classwizard.cpp 5
    \snippet dialogs/classwizard/classwizard.cpp 6

    If the user clicks \uicontrol Finish, we extract the information from
    the various pages using QWizard::field() and generate the files.
    The code is long and tedious (and has barely anything to do with
    noble art of designing wizards), so most of it is skipped here.
    See the actual example in the Qt distribution for the details if
    you're curious.

    \section1 The IntroPage Class

    The pages are defined in \c classwizard.h and implemented in \c
    classwizard.cpp, together with \c ClassWizard. We will start with
    the easiest page:

    \snippet dialogs/classwizard/classwizard.h 1
    \codeline
    \snippet dialogs/classwizard/classwizard.cpp 7

    A page inherits from QWizardPage. We set a
    \l{QWizardPage::}{title} and a
    \l{QWizard::WatermarkPixmap}{watermark pixmap}. By not setting
    any \l{QWizardPage::}{subTitle}, we ensure that no header is
    displayed for this page. (On Windows, it is customary for wizards
    to display a watermark pixmap on the first and last pages, and to
    have a header on the other pages.)

    Then we create a QLabel and add it to a layout.

    \section1 The ClassInfoPage Class

    The second page is defined and implemented as follows:

    \snippet dialogs/classwizard/classwizard.h 2
    \codeline
    \snippet dialogs/classwizard/classwizard.cpp 9
    \dots
    \snippet dialogs/classwizard/classwizard.cpp 12
    \dots
    \snippet dialogs/classwizard/classwizard.cpp 13

    First, we set the page's \l{QWizardPage::}{title},
    \l{QWizardPage::}{subTitle}, and \l{QWizard::LogoPixmap}{logo
    pixmap}. The logo pixmap is displayed in the page's header in
    \l{QWizard::}{ClassicStyle} and \l{QWizard::}{ModernStyle}.

    Then we create the child widgets, create \l{Registering and Using
    Fields}{wizard fields} associated with them, and put them into
    layouts. The \c className field is created with an asterisk (\c
    *) next to its name. This makes it a \l{mandatory fields}{mandatory field}, that
    is, a field that must be filled before the user can press the
    \uicontrol Next button (\uicontrol Continue on \macos). The fields' values
    can be accessed from any other page using QWizardPage::field(),
    or from the wizard code using QWizard::field().

    \section1 The CodeStylePage Class

    The third page is defined and implemented as follows:

    \snippet dialogs/classwizard/classwizard.h 3
    \codeline
    \snippet dialogs/classwizard/classwizard.cpp 14
    \dots
    \snippet dialogs/classwizard/classwizard.cpp 15
    \codeline
    \snippet dialogs/classwizard/classwizard.cpp 16

    The code in the constructor is very similar to what we did for \c
    ClassInfoPage, so we skipped most of it.

    The \c initializePage() function is what makes this class
    interesting. It is reimplemented from QWizardPage and is used to
    initialize some of the page's fields with values from the
    previous page (namely, \c className and \c baseClass). For
    example, if the class name on page 2 is \c SuperDuperWidget, the
    default macro name on page 3 is \c SUPERDUPERWIDGET_H.

    The \c OutputFilesPage and \c ConclusionPage classes are very
    similar to \c CodeStylePage, so we won't review them here.

    \sa QWizard, {License Wizard Example}, {Trivial Wizard Example}
*/