qt_demoe/third/designer/lib/shared/qdesigner_widgetitem.cpp

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12 KiB
C++

/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the Qt Designer of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 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 the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
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** $QT_END_LICENSE$
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****************************************************************************/
#include "qdesigner_widgetitem_p.h"
#include "qdesigner_widget_p.h"
#include "widgetfactory_p.h"
#include <QtDesigner/QDesignerFormWindowInterface>
#include <QtDesigner/QExtensionManager>
#include <QtDesigner/QDesignerFormEditorInterface>
#include <QtDesigner/QDesignerContainerExtension>
#include <QtDesigner/QDesignerWidgetDataBaseInterface>
#include <QtGui/QVBoxLayout>
#include <QtGui/QHBoxLayout>
#include <QtGui/QGridLayout>
#include <QtGui/QFormLayout>
#include <QtGui/QApplication>
#include <QtCore/QTextStream>
#include <QtCore/QDebug>
#include <private/qlayout_p.h>
QT_BEGIN_NAMESPACE
enum { DebugWidgetItem = 0 };
enum { MinimumLength = 10 };
// Widget item creation function to be registered as factory method with
// QLayoutPrivate
static QWidgetItem *createDesignerWidgetItem(const QLayout *layout, QWidget *widget)
{
Qt::Orientations orientations;
if (qdesigner_internal::QDesignerWidgetItem::check(layout, widget, &orientations)) {
if (DebugWidgetItem)
qDebug() << "QDesignerWidgetItem: Creating on " << layout << widget << orientations;
return new qdesigner_internal::QDesignerWidgetItem(layout, widget, orientations);
}
if (DebugWidgetItem)
qDebug() << "QDesignerWidgetItem: Noncontainer: " << layout << widget;
return 0;
}
static QString sizePolicyToString(const QSizePolicy &p)
{
QString rc; {
QTextStream str(&rc);
str << "Control=" << p.controlType() << " expdirs=" << p.expandingDirections()
<< " hasHeightForWidth=" << p.hasHeightForWidth()
<< " H: Policy=" << p.horizontalPolicy()
<< " stretch=" << p.horizontalStretch()
<< " V: Policy=" << p.verticalPolicy()
<< " stretch=" << p.verticalStretch();
}
return rc;
}
// Find the layout the item is contained in, recursing over
// child layouts
static const QLayout *findLayoutOfItem(const QLayout *haystack, const QLayoutItem *needle)
{
const int count = haystack->count();
for (int i = 0; i < count; i++) {
QLayoutItem *item = haystack->itemAt(i);
if (item == needle)
return haystack;
if (QLayout *childLayout = item->layout())
if (const QLayout *containing = findLayoutOfItem(childLayout, needle))
return containing;
}
return 0;
}
namespace qdesigner_internal {
// ------------------ QDesignerWidgetItem
QDesignerWidgetItem::QDesignerWidgetItem(const QLayout *containingLayout, QWidget *w, Qt::Orientations o) :
QWidgetItemV2(w),
m_orientations(o),
m_nonLaidOutMinSize(w->minimumSizeHint()),
m_nonLaidOutSizeHint(w->sizeHint()),
m_cachedContainingLayout(containingLayout)
{
// Initialize the minimum size to prevent nonlaid-out frames/widgets
// from being slammed to zero
const QSize minimumSize = w->minimumSize();
if (!minimumSize.isEmpty())
m_nonLaidOutMinSize = minimumSize;
expand(&m_nonLaidOutMinSize);
expand(&m_nonLaidOutSizeHint);
w->installEventFilter(this);
connect(containingLayout, SIGNAL(destroyed()), this, SLOT(layoutChanged()));
if (DebugWidgetItem )
qDebug() << "QDesignerWidgetItem" << w << sizePolicyToString(w->sizePolicy()) << m_nonLaidOutMinSize << m_nonLaidOutSizeHint;
}
void QDesignerWidgetItem::expand(QSize *s) const
{
// Expand the size if its too small
if (m_orientations & Qt::Horizontal && s->width() <= 0)
s->setWidth(MinimumLength);
if (m_orientations & Qt::Vertical && s->height() <= 0)
s->setHeight(MinimumLength);
}
QSize QDesignerWidgetItem::minimumSize() const
{
// Just track the size in case we are laid-out or stretched.
const QSize baseMinSize = QWidgetItemV2::minimumSize();
QWidget * w = constWidget();
if (w->layout() || subjectToStretch(containingLayout(), w)) {
m_nonLaidOutMinSize = baseMinSize;
return baseMinSize;
}
// Nonlaid out: Maintain last laid-out size
const QSize rc = baseMinSize.expandedTo(m_nonLaidOutMinSize);
if (DebugWidgetItem > 1)
qDebug() << "minimumSize" << constWidget() << baseMinSize << rc;
return rc;
}
QSize QDesignerWidgetItem::sizeHint() const
{
// Just track the size in case we are laid-out or stretched.
const QSize baseSizeHint = QWidgetItemV2::sizeHint();
QWidget * w = constWidget();
if (w->layout() || subjectToStretch(containingLayout(), w)) {
m_nonLaidOutSizeHint = baseSizeHint;
return baseSizeHint;
}
// Nonlaid out: Maintain last laid-out size
const QSize rc = baseSizeHint.expandedTo(m_nonLaidOutSizeHint);
if (DebugWidgetItem > 1)
qDebug() << "sizeHint" << constWidget() << baseSizeHint << rc;
return rc;
}
bool QDesignerWidgetItem::subjectToStretch(const QLayout *layout, QWidget *w)
{
if (!layout)
return false;
// Are we under some stretch factor?
if (const QBoxLayout *bl = qobject_cast<const QBoxLayout *>(layout)) {
const int index = bl->indexOf(w);
Q_ASSERT(index != -1);
return bl->stretch(index) != 0;
}
if (const QGridLayout *cgl = qobject_cast<const QGridLayout *>(layout)) {
QGridLayout *gl = const_cast<QGridLayout *>(cgl);
const int index = cgl->indexOf(w);
Q_ASSERT(index != -1);
int row, column, rowSpan, columnSpan;
gl->getItemPosition (index, &row, &column, &rowSpan, &columnSpan);
const int rend = row + rowSpan;
const int cend = column + columnSpan;
for (int r = row; r < rend; r++)
if (cgl->rowStretch(r) != 0)
return true;
for (int c = column; c < cend; c++)
if (cgl->columnStretch(c) != 0)
return true;
}
return false;
}
/* Return the orientations mask for a layout, specifying
* in which directions squeezing should be prevented. */
static Qt::Orientations layoutOrientation(const QLayout *layout)
{
if (const QBoxLayout *bl = qobject_cast<const QBoxLayout *>(layout)) {
const QBoxLayout::Direction direction = bl->direction();
return direction == QBoxLayout::LeftToRight || direction == QBoxLayout::RightToLeft ? Qt::Horizontal : Qt::Vertical;
}
if (qobject_cast<const QFormLayout*>(layout))
return Qt::Vertical;
return Qt::Horizontal|Qt::Vertical;
}
// Check for a non-container extension container
bool QDesignerWidgetItem::isContainer(const QDesignerFormEditorInterface *core, QWidget *w)
{
if (!WidgetFactory::isFormEditorObject(w))
return false;
const QDesignerWidgetDataBaseInterface *wdb = core->widgetDataBase();
const int widx = wdb->indexOfObject(w);
if (widx == -1 || !wdb->item(widx)->isContainer())
return false;
if (qt_extension<QDesignerContainerExtension*>(core->extensionManager(), w))
return false;
return true;
}
bool QDesignerWidgetItem::check(const QLayout *layout, QWidget *w, Qt::Orientations *ptrToOrientations)
{
// Check for form-editor non-containerextension-containers (QFrame, etc)
// within laid-out form editor widgets. No check for managed() here as we
// want container pages and widgets in the process of being morphed as
// well. Avoid nested layouts (as the effective stretch cannot be easily
// computed and may mess things up). Won't work for Q3 Group boxes.
if (ptrToOrientations)
*ptrToOrientations = 0;
const QObject *layoutParent = layout->parent();
if (!layoutParent || !layoutParent->isWidgetType() || !WidgetFactory::isFormEditorObject(layoutParent))
return false;
QDesignerFormWindowInterface *fw = QDesignerFormWindowInterface::findFormWindow(w);
if (!fw || !isContainer(fw->core(), w))
return false;
// If it is a box, restrict to its orientation
if (ptrToOrientations)
*ptrToOrientations = layoutOrientation(layout);
return true;
}
QSize QDesignerWidgetItem::nonLaidOutMinSize() const
{
return m_nonLaidOutMinSize;
}
void QDesignerWidgetItem::setNonLaidOutMinSize(const QSize &s)
{
if (DebugWidgetItem > 1)
qDebug() << "setNonLaidOutMinSize" << constWidget() << s;
m_nonLaidOutMinSize = s;
}
QSize QDesignerWidgetItem::nonLaidOutSizeHint() const
{
return m_nonLaidOutSizeHint;
}
void QDesignerWidgetItem::setNonLaidOutSizeHint(const QSize &s)
{
if (DebugWidgetItem > 1)
qDebug() << "setNonLaidOutSizeHint" << constWidget() << s;
m_nonLaidOutSizeHint = s;
}
void QDesignerWidgetItem::install()
{
QLayoutPrivate::widgetItemFactoryMethod = createDesignerWidgetItem;
}
void QDesignerWidgetItem::deinstall()
{
QLayoutPrivate::widgetItemFactoryMethod = 0;
}
const QLayout *QDesignerWidgetItem::containingLayout() const
{
if (!m_cachedContainingLayout) {
if (QWidget *parentWidget = constWidget()->parentWidget())
if (QLayout *parentLayout = parentWidget->layout()) {
m_cachedContainingLayout = findLayoutOfItem(parentLayout, this);
if (m_cachedContainingLayout)
connect(m_cachedContainingLayout, SIGNAL(destroyed()), this, SLOT(layoutChanged()));
}
if (DebugWidgetItem)
qDebug() << Q_FUNC_INFO << " found " << m_cachedContainingLayout << " after reparenting " << constWidget();
}
return m_cachedContainingLayout;
}
void QDesignerWidgetItem::layoutChanged()
{
if (DebugWidgetItem)
qDebug() << Q_FUNC_INFO;
m_cachedContainingLayout = 0;
}
bool QDesignerWidgetItem::eventFilter(QObject * /* watched */, QEvent *event)
{
if (event->type() == QEvent::ParentChange)
layoutChanged();
return false;
}
// ------------------ QDesignerWidgetItemInstaller
int QDesignerWidgetItemInstaller::m_instanceCount = 0;
QDesignerWidgetItemInstaller::QDesignerWidgetItemInstaller()
{
if (m_instanceCount++ == 0) {
if (DebugWidgetItem)
qDebug() << "QDesignerWidgetItemInstaller: installing";
QDesignerWidgetItem::install();
}
}
QDesignerWidgetItemInstaller::~QDesignerWidgetItemInstaller()
{
if (--m_instanceCount == 0) {
if (DebugWidgetItem)
qDebug() << "QDesignerWidgetItemInstaller: deinstalling";
QDesignerWidgetItem::deinstall();
}
}
}
QT_END_NAMESPACE