abstractformbuilder.cpp

QT 开发环境里面一个很重要的文件

/****************************************************************************
**
** Copyright (C) 1992-2006 Trolltech ASA. All rights reserved.
**
** This file is part of the Qt Designer of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file.  Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
** http://www.trolltech.com/products/qt/opensource.html
**
** If you are unsure which license is appropriate for your use, please
** review the following information:
** http://www.trolltech.com/products/qt/licensing.html or contact the
** sales department at [e-mail].
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
****************************************************************************/

#include "abstractformbuilder.h"
#include "ui4_p.h"

#include <QtCore/QVariant>
#include <QtCore/QMetaProperty>
#include <QtCore/QDateTime>
#include <QtCore/QFileInfo>
#include <QtCore/QDir>
#include <QtCore/QQueue>
#include <QtCore/QUrl>

#include <QtGui/QAction>
#include <QtGui/QActionGroup>
#include <QtGui/QComboBox>
#include <QtGui/QFontComboBox>
#include <QtGui/QGridLayout>
#include <QtGui/QIcon>
#include <QtGui/QListWidget>
#include <QtGui/QMainWindow>
#include <QtGui/QPixmap>
#include <QtGui/QStatusBar>
#include <QtGui/QTreeWidget>
#include <QtGui/QTableWidget>
#include <QtGui/QWidget>
#include <QtGui/QSplitter>

#include <QtXml/QDomDocument>

#include <QtGui/QDialog>

// containers
#include <QtGui/QToolBox>
#include <QtGui/QStackedWidget>
#include <QtGui/QTabWidget>
#include <QtGui/QToolBar>
#include <QtGui/QMenuBar>
#include <QtGui/QDockWidget>

#include <QtCore/qdebug.h>

#include <limits.h>
#include <private/qfont_p.h>

#ifdef QFORMINTERNAL_NAMESPACE
using namespace QFormInternal;
#endif

class QFriendlyLayout: public QLayout
{
public:
    inline QFriendlyLayout() { Q_ASSERT(0); }

#ifdef QFORMINTERNAL_NAMESPACE
    friend class QFormInternal::QAbstractFormBuilder;
#else
    friend class QAbstractFormBuilder;
#endif
};

class QAbstractFormBuilderGadget: public QWidget
{
    Q_OBJECT
    Q_PROPERTY(Qt::Orientation orientation READ fakeOrientation)
    Q_PROPERTY(QSizePolicy::Policy sizeType READ fakeSizeType)
    Q_PROPERTY(QPalette::ColorRole colorRole READ fakeColorRole)
    Q_PROPERTY(QPalette::ColorGroup colorGroup READ fakeColorGroup)
    Q_PROPERTY(Qt::BrushStyle brushStyle READ fakeBrushStyle)
    Q_PROPERTY(QGradient::Type gradientType READ fakeGradientType)
    Q_PROPERTY(QGradient::Spread gradientSpread READ fakeGradientSpread)
    Q_PROPERTY(QGradient::CoordinateMode gradientCoordinate READ fakeGradientCoordinate)
public:
    QAbstractFormBuilderGadget() { Q_ASSERT(0); }

    Qt::Orientation fakeOrientation() const     { Q_ASSERT(0); return Qt::Horizontal; }
    QSizePolicy::Policy fakeSizeType() const    { Q_ASSERT(0); return QSizePolicy::Expanding; }
    QPalette::ColorGroup fakeColorGroup() const { Q_ASSERT(0); return static_cast<QPalette::ColorGroup>(0); }
    QPalette::ColorRole fakeColorRole() const   { Q_ASSERT(0); return static_cast<QPalette::ColorRole>(0); }
    Qt::BrushStyle fakeBrushStyle() const       { Q_ASSERT(0); return Qt::NoBrush; }
    QGradient::Type fakeGradientType() const    { Q_ASSERT(0); return QGradient::NoGradient; }
    QGradient::Spread fakeGradientSpread() const  { Q_ASSERT(0); return QGradient::PadSpread; }
    QGradient::CoordinateMode fakeGradientCoordinate() const  { Q_ASSERT(0); return QGradient::LogicalMode; }
};

/*!
    \class QAbstractFormBuilder

    \brief The QAbstractFormBuilder class provides a default
    implementation for classes that create user interfaces at
    run-time.

    \inmodule QtDesigner

    QAbstractFormBuilder provides a standard interface and a default
    implementation for constructing forms from user interface
    files. It is not intended to be instantiated directly. Use the
    QFormBuilder class to create user interfaces from \c{.ui} files at
    run-time. For example:

    \code
        MyForm::MyForm(QWidget *parent)
            : QWidget(parent)
        {
            QFormBuilder builder;
            QFile file(":/forms/myWidget.ui");
            file.open(QFile::ReadOnly);
            QWidget *myWidget = builder.load(&file, this);
            file.close();

            QVBoxLayout *layout = new QVBoxLayout;
            layout->addWidget(myWidget);
            setLayout(layout);
        }
    \endcode

    To override certain aspects of the form builder's behavior,
    subclass QAbstractFormBuilder and reimplement the relevant virtual
    functions:

    \list
    \o load() handles reading of \c{.ui} format files from arbitrary
       QIODevices, and construction of widgets from the XML data
       that they contain.
    \o save() handles saving of widget details in \c{.ui} format to
       arbitrary QIODevices.
    \o workingDirectory() and setWorkingDirectory() control the
       directory in which forms are held. The form builder looks for
       other resources on paths relative to this directory.
    \endlist

    The QFormBuilder class is typically used by custom components and
    applications that embed \QD. Standalone applications that need to
    dynamically generate user interfaces at run-time use the
    QUiLoader, found in the QtUiTools module.

    \sa {QtUiTools Module}
*/

/*!
    Constructs a new form builder.*/
QAbstractFormBuilder::QAbstractFormBuilder()
{
    m_defaultMargin = INT_MIN;
    m_defaultSpacing = INT_MIN;
}

/*!
    Destroys the form builder.*/
QAbstractFormBuilder::~QAbstractFormBuilder()
{
}

/*!
    \fn QWidget *QAbstractFormBuilder::load(QIODevice *device, QWidget *parent)

    Loads an XML representation of a widget from the given \a device,
    and constructs a new widget with the specified \a parent.

    \sa save()
*/
QWidget *QAbstractFormBuilder::load(QIODevice *dev, QWidget *parentWidget)
{
    QDomDocument doc;
    if (!doc.setContent(dev))
        return 0;

    QDomElement root = doc.firstChild().toElement();
    DomUI ui;
    ui.read(root); /// ### check the result

    return create(&ui, parentWidget);
}

/*!
    \internal
*/
QWidget *QAbstractFormBuilder::create(DomUI *ui, QWidget *parentWidget)
{
    if (DomLayoutDefault *def = ui->elementLayoutDefault()) {
        m_defaultMargin = def->hasAttributeMargin() ? def->attributeMargin() : INT_MIN;
        m_defaultSpacing = def->hasAttributeSpacing() ? def->attributeSpacing() : INT_MIN;
    }

    DomWidget *ui_widget = ui->elementWidget();
    if (!ui_widget)
        return 0;

    createCustomWidgets(ui->elementCustomWidgets());

    if (QWidget *widget = create(ui_widget, parentWidget)) {
        createConnections(ui->elementConnections(), widget);
        createResources(ui->elementResources());
        applyTabStops(widget, ui->elementTabStops());
        reset();

        return widget;
    }

    return 0;
}

/*!
    \internal
*/
QWidget *QAbstractFormBuilder::create(DomWidget *ui_widget, QWidget *parentWidget)
{
    QWidget *w = createWidget(ui_widget->attributeClass(), parentWidget, ui_widget->attributeName());
    if (!w)
        return 0;

    applyProperties(w, ui_widget->elementProperty());

    foreach (DomAction *ui_action, ui_widget->elementAction()) {
        QAction *child_action = create(ui_action, w);
        Q_UNUSED( child_action );
    }

    foreach (DomActionGroup *ui_action_group, ui_widget->elementActionGroup()) {
        QActionGroup *child_action_group = create(ui_action_group, w);
        Q_UNUSED( child_action_group );
    }

    foreach (DomWidget *ui_child, ui_widget->elementWidget()) {
        QWidget *child_w = create(ui_child, w);
        Q_UNUSED( child_w );
    }

    foreach (DomLayout *ui_lay, ui_widget->elementLayout()) {
        QLayout *child_lay = create(ui_lay, 0, w);
        Q_UNUSED( child_lay );
    }

    foreach (DomActionRef *ui_action_ref, ui_widget->elementAddAction()) {
        QString name = ui_action_ref->attributeName();
        if (name == QLatin1String("separator")) {
            QAction *sep = new QAction(w);
            sep->setSeparator(true);
            w->addAction(sep);
            addMenuAction(sep);
        } else if (QAction *a = m_actions.value(name)) {
            w->addAction(a);
        } else if (QActionGroup *g = m_actionGroups.value(name)) {
            w->addActions(g->actions());
        } else if (QMenu *menu = qFindChild<QMenu*>(w, name)) {
            w->addAction(menu->menuAction());
            addMenuAction(menu->menuAction());
        }
    }

    loadExtraInfo(ui_widget, w, parentWidget);
    addItem(ui_widget, w, parentWidget);

    if (qobject_cast<QDialog *>(w) && parentWidget)
        w->setAttribute(Qt::WA_Moved, false); // So that QDialog::setVisible(true) will center it

    return w;
}

/*!
    \internal
*/
QAction *QAbstractFormBuilder::create(DomAction *ui_action, QObject *parent)
{
    QAction *a = createAction(parent, ui_action->attributeName());
    if (!a)
        return 0;

    applyProperties(a, ui_action->elementProperty());
    return a;
}

/*!
    \internal
*/
QActionGroup *QAbstractFormBuilder::create(DomActionGroup *ui_action_group, QObject *parent)
{
    QActionGroup *a = createActionGroup(parent, ui_action_group->attributeName());
    if (!a)
        return 0;

    applyProperties(a, ui_action_group->elementProperty());

    foreach (DomAction *ui_action, ui_action_group->elementAction()) {
        QAction *child_action = create(ui_action, a);
        Q_UNUSED( child_action );
    }

    foreach (DomActionGroup *g, ui_action_group->elementActionGroup()) {
        QActionGroup *child_action_group = create(g, parent);
        Q_UNUSED( child_action_group );
    }

    return a;
}

/*!
    \internal
*/
bool QAbstractFormBuilder::addItem(DomWidget *ui_widget, QWidget *widget, QWidget *parentWidget)
{
    QHash<QString, DomProperty*> attributes = propertyMap(ui_widget->elementAttribute());

    QString title = QLatin1String("Page");
    if (DomProperty *ptitle = attributes.value(QLatin1String("title"))) {
        title = toString(ptitle->elementString());
    }

    QString label = QLatin1String(QLatin1String("Page"));
    if (DomProperty *plabel = attributes.value(QLatin1String("label"))) {
        label = toString(plabel->elementString());
    }

    if (QMainWindow *mw = qobject_cast<QMainWindow*>(parentWidget)) {

        // the menubar
        if (QMenuBar *menuBar = qobject_cast<QMenuBar*>(widget)) {
            mw->setMenuBar(menuBar);
            return true;
        }

        // apply the toolbar's attributes
        else if (QToolBar *toolBar = qobject_cast<QToolBar*>(widget)) {
            if (DomProperty *attr = attributes.value(QLatin1String("toolBarArea"))) {
                Qt::ToolBarArea area = static_cast<Qt::ToolBarArea>(attr->elementNumber());
                mw->addToolBar(area, toolBar);
            } else {
                mw->addToolBar(toolBar);
            }
            return true;
        }

        // statusBar
        else if (QStatusBar *statusBar = qobject_cast<QStatusBar*>(widget)) {
            mw->setStatusBar(statusBar);
            return true;
        }

        // apply the dockwidget's attributes
        else if (QDockWidget *dockWidget = qobject_cast<QDockWidget*>(widget)) {
            if (DomProperty *attr = attributes.value(QLatin1String("dockWidgetArea"))) {
                Qt::DockWidgetArea area = static_cast<Qt::DockWidgetArea>(attr->elementNumber());
                if (!dockWidget->isAreaAllowed(area)) {
                    if (dockWidget->isAreaAllowed(Qt::LeftDockWidgetArea))
                        area = Qt::LeftDockWidgetArea;
                    else if (dockWidget->isAreaAllowed(Qt::RightDockWidgetArea))
                        area = Qt::RightDockWidgetArea;
                    else if (dockWidget->isAreaAllowed(Qt::TopDockWidgetArea))
                        area = Qt::TopDockWidgetArea;
                    else if (dockWidget->isAreaAllowed(Qt::BottomDockWidgetArea))
                        area = Qt::BottomDockWidgetArea;
                }
                mw->addDockWidget(area, dockWidget);
            } else {
                mw->addDockWidget(Qt::LeftDockWidgetArea, dockWidget);
            }
            return true;
        }

        else if (! mw->centralWidget()) {
            mw->setCentralWidget(widget);
            return true;
        }
    }

    else if (QTabWidget *tabWidget = qobject_cast<QTabWidget*>(parentWidget)) {
        widget->setParent(0);

        int tabIndex = tabWidget->count();
        tabWidget->addTab(widget, title);

        if (DomProperty *picon = attributes.value(QLatin1String("icon"))) {
            tabWidget->setTabIcon(tabIndex, qvariant_cast<QIcon>(toVariant(0, picon)));
        }

        if (DomProperty *ptoolTip = attributes.value(QLatin1String("toolTip"))) {
            tabWidget->setTabToolTip(tabIndex, toString(ptoolTip->elementString()));
        }