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Diffstat (limited to 'src/imports/labsmodels/qqmldelegatecomponent.cpp')
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diff --git a/src/imports/labsmodels/qqmldelegatecomponent.cpp b/src/imports/labsmodels/qqmldelegatecomponent.cpp new file mode 100644 index 0000000000..b3c9afbb97 --- /dev/null +++ b/src/imports/labsmodels/qqmldelegatecomponent.cpp @@ -0,0 +1,305 @@ +/**************************************************************************** +** +** Copyright (C) 2018 The Qt Company Ltd. +** Contact: https://www.qt.io/licensing/ +** +** This file is part of the QtQml 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. +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qqmldelegatecomponent_p.h" +#include <QtQmlModels/private/qqmladaptormodel_p.h> + +QT_BEGIN_NAMESPACE + +/*! + \qmltype DelegateChoice + \instantiates QQmlDelegateChoice + \inqmlmodule Qt.labs.qmlmodels + \brief Encapsulates a delegate and when to use it. + + The DelegateChoice type wraps a delegate and defines the circumstances + in which it should be chosen. + + DelegateChoices can be nested inside a DelegateChooser. + + \sa DelegateChooser +*/ + +/*! + \qmlproperty string QtQml.Models::DelegateChoice::roleValue + This property holds the value used to match the role data for the role provided by \l DelegateChooser::role. +*/ +QVariant QQmlDelegateChoice::roleValue() const +{ + return m_value; +} + +void QQmlDelegateChoice::setRoleValue(const QVariant &value) +{ + if (m_value == value) + return; + m_value = value; + emit roleValueChanged(); + emit changed(); +} + +/*! + \qmlproperty index QtQml.Models::DelegateChoice::row + This property holds the value used to match the row value of model elements. + With models that have only the index property (and thus only one column), this property + should be intended as an index, and set to the desired index value. + + \note Setting both row and index has undefined behavior. The two are equivalent and only + one should be used. + + \sa index +*/ + +/*! + \qmlproperty index QtQml.Models::DelegateChoice::index + This property holds the value used to match the index value of model elements. + This is effectively an alias for \l row. + + \sa row +*/ +int QQmlDelegateChoice::row() const +{ + return m_row; +} + +void QQmlDelegateChoice::setRow(int r) +{ + if (m_row == r) + return; + m_row = r; + emit rowChanged(); + emit indexChanged(); + emit changed(); +} + +/*! + \qmlproperty index QtQml.Models::DelegateChoice::column + This property holds the value used to match the column value of model elements. +*/ +int QQmlDelegateChoice::column() const +{ + return m_column; +} + +void QQmlDelegateChoice::setColumn(int c) +{ + if (m_column == c) + return; + m_column = c; + emit columnChanged(); + emit changed(); +} + +QQmlComponent *QQmlDelegateChoice::delegate() const +{ + return m_delegate; +} + +/*! + \qmlproperty Component QtQml.Models::DelegateChoice::delegate + This property holds the delegate to use if this choice matches the model item. +*/ +void QQmlDelegateChoice::setDelegate(QQmlComponent *delegate) +{ + if (m_delegate == delegate) + return; + QQmlAbstractDelegateComponent *adc = static_cast<QQmlAbstractDelegateComponent *>(m_delegate); + if (adc) + disconnect(adc, &QQmlAbstractDelegateComponent::delegateChanged, this, &QQmlDelegateChoice::delegateChanged); + m_delegate = delegate; + adc = static_cast<QQmlAbstractDelegateComponent *>(delegate); + if (adc) + connect(adc, &QQmlAbstractDelegateComponent::delegateChanged, this, &QQmlDelegateChoice::delegateChanged); + emit delegateChanged(); + emit changed(); +} + +bool QQmlDelegateChoice::match(int row, int column, const QVariant &value) const +{ + if (!m_value.isValid() && m_row < 0 && m_column < 0) + return true; + + const bool roleMatched = (m_value.isValid()) ? value == m_value : true; + const bool rowMatched = (m_row < 0 ) ? true : m_row == row; + const bool columnMatched = (m_column < 0 ) ? true : m_column == column; + return roleMatched && rowMatched && columnMatched; +} + +/*! + \qmltype DelegateChooser + \instantiates QQmlDelegateChooser + \inqmlmodule Qt.labs.qmlmodels + \brief Allows a view to use different delegates for different types of items in the model. + + The DelegateChooser is a special \l Component type intended for those scenarios where a Component is required + by a view and used as a delegate. + DelegateChooser encapsulates a set of \l {DelegateChoice}s. + These choices are used to determine the delegate that will be instantiated for each + item in the model. + The selection of the choice is performed based on the value that a model item has for \l role, + and also based on index. + + DelegateChooser is commonly used when a view needs to display a set of delegates that are significantly + different from each other. For example, a typical phone settings view might include toggle switches, + sliders, radio buttons, and other visualizations based on the type of each setting. In this case, DelegateChooser + could provide an easy way to associate a different type of delegate with each setting: + + \qml \QtMinorVersion + import QtQuick 2.\1 + import QtQuick.Controls 2.\1 + import Qt.labs.qmlmodels 1.0 + + ListView { + width: 200; height: 400 + + ListModel { + id: listModel + ListElement { type: "info"; ... } + ListElement { type: "switch"; ... } + ListElement { type: "swipe"; ... } + ListElement { type: "switch"; ... } + } + + DelegateChooser { + id: chooser + role: "type" + DelegateChoice { roleValue: "info"; ItemDelegate { ... } } + DelegateChoice { roleValue: "switch"; SwitchDelegate { ... } } + DelegateChoice { roleValue: "swipe"; SwipeDelegate { ... } } + } + + model: listModel + delegate: chooser + } + \endqml + + \note This type is intended to transparently work only with TableView and any DelegateModel-based view. + Views (including user-defined views) that aren't internally based on a DelegateModel need to explicitly support + this type of component to make it function as described. + + \sa DelegateChoice +*/ + +/*! + \qmlproperty string QtQml.Models::DelegateChooser::role + This property holds the role used to determine the delegate for a given model item. + + \sa DelegateChoice +*/ +void QQmlDelegateChooser::setRole(const QString &role) +{ + if (m_role == role) + return; + m_role = role; + emit roleChanged(); +} + +/*! + \qmlproperty list<DelegateChoice> QtQml.Models::DelegateChooser::choices + \default + + The list of DelegateChoices for the chooser. + + The list is treated as an ordered list, where the first DelegateChoice to match + will be used be a view. + + It should not generally be necessary to refer to the \c choices property, + as it is the default property for DelegateChooser and thus all child items are + automatically assigned to this property. +*/ + +QQmlListProperty<QQmlDelegateChoice> QQmlDelegateChooser::choices() +{ + return QQmlListProperty<QQmlDelegateChoice>(this, nullptr, + QQmlDelegateChooser::choices_append, + QQmlDelegateChooser::choices_count, + QQmlDelegateChooser::choices_at, + QQmlDelegateChooser::choices_clear); +} + +void QQmlDelegateChooser::choices_append(QQmlListProperty<QQmlDelegateChoice> *prop, QQmlDelegateChoice *choice) +{ + QQmlDelegateChooser *q = static_cast<QQmlDelegateChooser *>(prop->object); + q->m_choices.append(choice); + connect(choice, &QQmlDelegateChoice::changed, q, &QQmlAbstractDelegateComponent::delegateChanged); + q->delegateChanged(); +} + +int QQmlDelegateChooser::choices_count(QQmlListProperty<QQmlDelegateChoice> *prop) +{ + QQmlDelegateChooser *q = static_cast<QQmlDelegateChooser*>(prop->object); + return q->m_choices.count(); +} + +QQmlDelegateChoice *QQmlDelegateChooser::choices_at(QQmlListProperty<QQmlDelegateChoice> *prop, int index) +{ + QQmlDelegateChooser *q = static_cast<QQmlDelegateChooser*>(prop->object); + return q->m_choices.at(index); +} + +void QQmlDelegateChooser::choices_clear(QQmlListProperty<QQmlDelegateChoice> *prop) +{ + QQmlDelegateChooser *q = static_cast<QQmlDelegateChooser *>(prop->object); + for (QQmlDelegateChoice *choice : q->m_choices) + disconnect(choice, &QQmlDelegateChoice::changed, q, &QQmlAbstractDelegateComponent::delegateChanged); + q->m_choices.clear(); + q->delegateChanged(); +} + +QQmlComponent *QQmlDelegateChooser::delegate(QQmlAdaptorModel *adaptorModel, int row, int column) const +{ + QVariant v; + if (!m_role.isNull()) + v = value(adaptorModel, row, column, m_role); + if (!v.isValid()) { // check if the row only has modelData, for example if the row is a QVariantMap + v = value(adaptorModel, row, column, QStringLiteral("modelData")); + if (v.isValid()) + v = v.toMap().value(m_role); + } + // loop through choices, finding first one that fits + for (int i = 0; i < m_choices.count(); ++i) { + const QQmlDelegateChoice *choice = m_choices.at(i); + if (choice->match(row, column, v)) + return choice->delegate(); + } + + return nullptr; +} + +QT_END_NAMESPACE |