diff options
Diffstat (limited to 'src/widgets/widgets/qscrollarea.cpp')
| -rw-r--r-- | src/widgets/widgets/qscrollarea.cpp | 64 |
1 files changed, 20 insertions, 44 deletions
diff --git a/src/widgets/widgets/qscrollarea.cpp b/src/widgets/widgets/qscrollarea.cpp index f7a4f8e446..efbf4da07f 100644 --- a/src/widgets/widgets/qscrollarea.cpp +++ b/src/widgets/widgets/qscrollarea.cpp @@ -1,41 +1,5 @@ -/**************************************************************************** -** -** Copyright (C) 2016 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** This file is part of the QtWidgets module of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** Commercial License Usage -** Licensees holding valid commercial Qt licenses may use this file in -** accordance with the commercial license agreement provided with the -** Software or, alternatively, in accordance with the terms contained in -** a written agreement between you and The Qt Company. For licensing terms -** and conditions see https://www.qt.io/terms-conditions. For further -** information use the contact form at https://www.qt.io/contact-us. -** -** GNU Lesser General Public License Usage -** Alternatively, this file may be used under the terms of the GNU Lesser -** General Public License version 3 as published by the Free Software -** Foundation and appearing in the file LICENSE.LGPL3 included in the -** packaging of this file. Please review the following information to -** ensure the GNU Lesser General Public License version 3 requirements -** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU -** General Public License version 2.0 or (at your option) the GNU General -** Public license version 3 or any later version approved by the KDE Free -** Qt Foundation. The licenses are as published by the Free Software -** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 -** included in the packaging of this file. Please review the following -** information to ensure the GNU General Public License requirements will -** be met: https://www.gnu.org/licenses/gpl-2.0.html and -** https://www.gnu.org/licenses/gpl-3.0.html. -** -** $QT_END_LICENSE$ -** -****************************************************************************/ +// Copyright (C) 2016 The Qt Company Ltd. +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only #include "qscrollarea.h" #include "private/qscrollarea_p.h" @@ -127,11 +91,7 @@ QT_BEGIN_NAMESPACE cause the size of the scroll area to be updated whenever the contents of the layout changes. - For a complete example using the QScrollArea class, see the \l - {widgets/imageviewer}{Image Viewer} example. The example shows how - to combine QLabel and QScrollArea to display an image. - - \sa QAbstractScrollArea, QScrollBar, {Image Viewer Example} + \sa QAbstractScrollArea, QScrollBar */ @@ -196,7 +156,23 @@ void QScrollAreaPrivate::updateScrollBars() if (resizable) { if ((widget->layout() ? widget->layout()->hasHeightForWidth() : widget->sizePolicy().hasHeightForWidth())) { QSize p_hfw = p.expandedTo(min).boundedTo(max); - int h = widget->heightForWidth( p_hfw.width() ); + int h = widget->heightForWidth(p_hfw.width()); + // If the height we calculated requires a vertical scrollbar, + // then we need to constrain the width and calculate the height again, + // otherwise we end up flipping the scrollbar on and off all the time. + if (vbarpolicy == Qt::ScrollBarAsNeeded) { + int vbarWidth = vbar->sizeHint().width(); + QSize m_hfw = m.expandedTo(min).boundedTo(max); + // is there any point in searching? + if (widget->heightForWidth(m_hfw.width() - vbarWidth) <= m.height()) { + while (h > m.height() && vbarWidth) { + --vbarWidth; + --m_hfw.rwidth(); + h = widget->heightForWidth(m_hfw.width()); + } + } + max = QSize(m_hfw.width(), qMax(m_hfw.height(), h)); + } min = QSize(p_hfw.width(), qMax(p_hfw.height(), h)); } } |