From 29bcbeab90210da80234529905d17280374f9684 Mon Sep 17 00:00:00 2001 From: Olivier Goffart Date: Wed, 1 Feb 2017 09:16:34 +0100 Subject: Deprecate QSignalMapper Does not make much sense now that we can connect to lambda functions [ChangeLog][QtCore][QSignalMapper] QSignalMapper is now marked as deprecated. Change-Id: I89135f23fdf16b42142a125eb7c9a86084c90bfc Reviewed-by: Sze Howe Koh --- .../widgets/mainwindows/mainwindow/mainwindow.cpp | 1 - .../doc/snippets/qsignalmapper/buttonwidget.cpp | 16 +++ .../doc/snippets/signalmapper/filereader.cpp | 117 --------------------- .../doc/src/objectmodel/signalsandslots.qdoc | 22 +--- src/corelib/kernel/qobject.cpp | 2 +- src/corelib/kernel/qsignalmapper.cpp | 8 +- src/corelib/kernel/qsignalmapper.h | 6 +- 7 files changed, 34 insertions(+), 138 deletions(-) delete mode 100644 src/corelib/doc/snippets/signalmapper/filereader.cpp diff --git a/examples/widgets/mainwindows/mainwindow/mainwindow.cpp b/examples/widgets/mainwindows/mainwindow/mainwindow.cpp index 10e3dd045a..afceddfca1 100644 --- a/examples/widgets/mainwindows/mainwindow/mainwindow.cpp +++ b/examples/widgets/mainwindows/mainwindow/mainwindow.cpp @@ -63,7 +63,6 @@ #include #include #include -#include #include #include #include diff --git a/src/corelib/doc/snippets/qsignalmapper/buttonwidget.cpp b/src/corelib/doc/snippets/qsignalmapper/buttonwidget.cpp index 39b03f5ff3..e91c41b305 100644 --- a/src/corelib/doc/snippets/qsignalmapper/buttonwidget.cpp +++ b/src/corelib/doc/snippets/qsignalmapper/buttonwidget.cpp @@ -49,6 +49,7 @@ ****************************************************************************/ #include +#include #include "buttonwidget.h" @@ -74,3 +75,18 @@ ButtonWidget::ButtonWidget(const QStringList &texts, QWidget *parent) setLayout(gridLayout); } //! [2] + +//! [3] +ButtonWidget::ButtonWidget(const QStringList &texts, QWidget *parent) + : QWidget(parent) +{ + QGridLayout *gridLayout = new QGridLayout; + for (int i = 0; i < texts.size(); ++i) { + QString text = texts[i]; + QPushButton *button = new QPushButton(text); + connect(button, &QPushButton::clicked, [=] { clicked(text); }); + gridLayout->addWidget(button, i / 3, i % 3); + } + setLayout(gridLayout); +} +//! [3] diff --git a/src/corelib/doc/snippets/signalmapper/filereader.cpp b/src/corelib/doc/snippets/signalmapper/filereader.cpp deleted file mode 100644 index 674f73d671..0000000000 --- a/src/corelib/doc/snippets/signalmapper/filereader.cpp +++ /dev/null @@ -1,117 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2016 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** This file is part of the config.tests of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:BSD$ -** 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. -** -** BSD License Usage -** Alternatively, you may use this file under the terms of the BSD license -** as follows: -** -** "Redistribution and use in source and binary forms, with or without -** modification, are permitted provided that the following conditions are -** met: -** * Redistributions of source code must retain the above copyright -** notice, this list of conditions and the following disclaimer. -** * Redistributions in binary form must reproduce the above copyright -** notice, this list of conditions and the following disclaimer in -** the documentation and/or other materials provided with the -** distribution. -** * Neither the name of The Qt Company Ltd nor the names of its -** contributors may be used to endorse or promote products derived -** from this software without specific prior written permission. -** -** -** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR -** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT -** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE -** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -#include -#include "filereader.h" - - -FileReader::FileReader(QWidget *parent) - : QWidget(parent) -{ - textEdit = new QTextEdit; - - taxFileButton = new QPushButton("Tax File"); - accountFileButton = new QPushButton("Accounts File"); - reportFileButton = new QPushButton("Report File"); - -//! [0] - signalMapper = new QSignalMapper(this); - signalMapper->setMapping(taxFileButton, QString("taxfile.txt")); - signalMapper->setMapping(accountFileButton, QString("accountsfile.txt")); - signalMapper->setMapping(reportFileButton, QString("reportfile.txt")); - - connect(taxFileButton, &QPushButton::clicked, - signalMapper, &QSignalMapper::map); - connect(accountFileButton, &QPushButton::clicked, - signalMapper, &QSignalMapper::map); - connect(reportFileButton, &QPushButton::clicked, - signalMapper, &QSignalMapper::map); -//! [0] - -//! [1] - connect(signalMapper, SIGNAL(mapped(QString)), - this, SLOT(readFile(QString))); -//! [1] - -/* -//! [2] - //slower due to signature normalization at runtime - - connect(signalMapper, SIGNAL(mapped(QString)), - this, SLOT(readFile(QString))); -//! [2] -*/ - QHBoxLayout *buttonLayout = new QHBoxLayout; - buttonLayout->addWidget(taxFileButton); - buttonLayout->addWidget(accountFileButton); - buttonLayout->addWidget(reportFileButton); - - QVBoxLayout *mainLayout = new QVBoxLayout; - mainLayout->addWidget(textEdit); - mainLayout->addLayout(buttonLayout); - - setLayout(mainLayout); -} - -void FileReader::readFile(const QString &filename) -{ - QFile file(filename); - - if (!file.open(QIODevice::ReadOnly)) { - QMessageBox::information(this, tr("Unable to open file"), - file.errorString()); - return; - } - - - QTextStream in(&file); - textEdit->setPlainText(in.readAll()); -} - diff --git a/src/corelib/doc/src/objectmodel/signalsandslots.qdoc b/src/corelib/doc/src/objectmodel/signalsandslots.qdoc index ed61511c62..6d3064d217 100644 --- a/src/corelib/doc/src/objectmodel/signalsandslots.qdoc +++ b/src/corelib/doc/src/objectmodel/signalsandslots.qdoc @@ -395,24 +395,12 @@ signal, Qt provides the QObject::sender() function, which returns a pointer to the object that sent the signal. - The QSignalMapper class is provided for situations where many - signals are connected to the same slot and the slot needs to - handle each signal differently. + Lambda expressions are a convenient way to pass custom arguments to a slot: - Suppose you have three push buttons that determine which file you - will open: "Tax File", "Accounts File", or "Report File". - - In order to open the correct file, you use QSignalMapper::setMapping() to - map all the QPushButton::clicked() signals to a QSignalMapper object. Then you connect - the file's QPushButton::clicked() signal to the QSignalMapper::map() slot. - - \snippet signalmapper/filereader.cpp 0 - - Then, you connect the \l{QSignalMapper::}{mapped()} signal to - \c{readFile()} where a different file will be opened, depending on - which push button is pressed. - - \snippet signalmapper/filereader.cpp 1 + \code + connect(action, &QAction::triggered, engine, + [=]() { engine->processAction(action->text()); }); + \endcode \sa {Meta-Object System}, {Qt's Property System} diff --git a/src/corelib/kernel/qobject.cpp b/src/corelib/kernel/qobject.cpp index 2f4f76856f..fe7cf7bbb1 100644 --- a/src/corelib/kernel/qobject.cpp +++ b/src/corelib/kernel/qobject.cpp @@ -2339,7 +2339,7 @@ static void err_info_about_objects(const char * func, a thread different from this object's thread. Do not use this function in this type of scenario. - \sa senderSignalIndex(), QSignalMapper + \sa senderSignalIndex() */ QObject *QObject::sender() const diff --git a/src/corelib/kernel/qsignalmapper.cpp b/src/corelib/kernel/qsignalmapper.cpp index a483717da5..d56965281e 100644 --- a/src/corelib/kernel/qsignalmapper.cpp +++ b/src/corelib/kernel/qsignalmapper.cpp @@ -58,10 +58,10 @@ public: }; - /*! \class QSignalMapper \inmodule QtCore + \obsolete \brief The QSignalMapper class bundles signals from identifiable senders. \ingroup objectmodel @@ -108,6 +108,12 @@ public: widget will emit a single \c clicked() signal whose argument is the text of the button the user clicked. + This class was mostly useful before lambda functions could be used as + slots. The example above can be rewritten simpler without QSignalMapper + by connecting to a lambda function. + + \snippet qsignalmapper/buttonwidget.cpp 3 + \sa QObject, QButtonGroup, QActionGroup */ diff --git a/src/corelib/kernel/qsignalmapper.h b/src/corelib/kernel/qsignalmapper.h index f960c7cabf..6c4cfa9627 100644 --- a/src/corelib/kernel/qsignalmapper.h +++ b/src/corelib/kernel/qsignalmapper.h @@ -42,6 +42,8 @@ #include +#if QT_DEPRECATED_SINCE(5, 10) + QT_BEGIN_NAMESPACE class QSignalMapperPrivate; @@ -51,7 +53,7 @@ class Q_CORE_EXPORT QSignalMapper : public QObject Q_OBJECT Q_DECLARE_PRIVATE(QSignalMapper) public: - explicit QSignalMapper(QObject *parent = Q_NULLPTR); + QT_DEPRECATED explicit QSignalMapper(QObject *parent = nullptr); ~QSignalMapper(); void setMapping(QObject *sender, int id); @@ -82,4 +84,6 @@ private: QT_END_NAMESPACE +#endif + #endif // QSIGNALMAPPER_H -- cgit v1.2.3