Selection support: support setting a QItemSelectionModel on TableView

Add support for assigning a QItemSelectionModel to TableView.
By doing so, delegate items that has a "required property selected"
defined will get this updated according to the state of the
selection model.

It's essential that the property is defined as "required". If not, the
property will simply be ignored by TableView. This is done to ensure
that existing applications that already has a "selected" property
defined, will continue to work as before, unaffected by the new
selection API.

[ChangeLog][QtQuick] TableView now supports selections by using an
ItemSelectionModel.

Task-number: QTBUG-74750
Change-Id: I4f4d75e9e65563b9aab0c54f3aa4aad2f6883952
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

3 files changed, 265 insertions, 0 deletions

diff --git a/tests/auto/quick/qquicktableview/data/tableviewwithselected1.qml b/tests/auto/quick/qquicktableview/data/tableviewwithselected1.qml
new file mode 100644
index 0000000000..efa0befaf5
--- /dev/null
+++ b/tests/auto/quick/qquicktableview/data/tableviewwithselected1.qml
@@ -0,0 +1,72 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQuick 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick
+import QtQuick.Window
+import QtQml.Models
+
+Item {
+    width: 640
+    height: 450
+
+    property alias tableView: tableView
+
+    TableView {
+        id: tableView
+        width: 600
+        height: 400
+        anchors.margins: 1
+        clip: true
+        delegate: tableViewDelegate
+        columnSpacing: 1
+        rowSpacing: 1
+    }
+
+    Component {
+        id: tableViewDelegate
+        Rectangle {
+            objectName: "tableViewDelegate"
+            implicitWidth: 100
+            implicitHeight: 100
+            required property bool selected
+            color: selected ? "lightgray" : "green"
+        }
+    }
+
+}
diff --git a/tests/auto/quick/qquicktableview/data/tableviewwithselected2.qml b/tests/auto/quick/qquicktableview/data/tableviewwithselected2.qml
new file mode 100644
index 0000000000..bb90d3f4bd
--- /dev/null
+++ b/tests/auto/quick/qquicktableview/data/tableviewwithselected2.qml
@@ -0,0 +1,78 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQuick 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick
+import QtQuick.Window
+import QtQml.Models
+
+Item {
+    width: 640
+    height: 450
+
+    property alias tableView: tableView
+
+    TableView {
+        id: tableView
+        width: 600
+        height: 400
+        anchors.margins: 1
+        clip: true
+        delegate: tableViewDelegate
+        columnSpacing: 1
+        rowSpacing: 1
+        selectionModel: ItemSelectionModel {
+            model: tableView.model
+        }
+
+    }
+
+    Component {
+        id: tableViewDelegate
+        Rectangle {
+            objectName: "tableViewDelegate"
+            implicitWidth: 100
+            implicitHeight: 100
+            // Add a selected property, but since it's not
+            // required, TableView should not touch it.
+            property bool selected
+            color: selected ? "lightgray" : "green"
+        }
+    }
+
+}
diff --git a/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp b/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp
index 6bd05c876f..dece7e53d9 100644
--- a/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp
+++ b/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp
@@ -198,6 +198,10 @@ private slots:
     void leftRightTopBottomProperties();
     void checkContentSize_data();
     void checkContentSize();
+    void checkSelectionModelWithRequiredSelectedProperty_data();
+    void checkSelectionModelWithRequiredSelectedProperty();
+    void checkSelectionModelWithUnrequiredSelectedProperty();
+    void removeAndAddSelectionModel();
 };
 
 tst_QQuickTableView::tst_QQuickTableView()
@@ -3451,6 +3455,117 @@ void tst_QQuickTableView::checkContentSize()
     QCOMPARE(tableView->contentHeight(), rowCount == 0 ? 0 : (rowCount * (delegateHeight + rowSpacing)) - rowSpacing);
 }
 
+void tst_QQuickTableView::checkSelectionModelWithRequiredSelectedProperty_data()
+{
+    QTest::addColumn<QVector<QPoint>>("selected");
+    QTest::addColumn<QPoint>("toggle");
+
+    QTest::newRow("nothing selected") << QVector<QPoint>() << QPoint(0,0);
+    QTest::newRow("one item selected") << (QVector<QPoint>() << QPoint(0, 0)) << QPoint(1, 1);
+    QTest::newRow("two items selected") << (QVector<QPoint>() << QPoint(1, 1) << QPoint(2, 2)) << QPoint(1, 1);
+}
+
+void tst_QQuickTableView::checkSelectionModelWithRequiredSelectedProperty()
+{
+    // Check that if you add a "required property selected" to the delegate,
+    // TableView will give it a value upon creation that matches the state
+    // in the selection model.
+    QFETCH(QVector<QPoint>, selected);
+    QFETCH(QPoint, toggle);
+
+    LOAD_TABLEVIEW("tableviewwithselected1.qml");
+
+    TestModel model(10, 10);
+    QItemSelectionModel selectionModel(&model);
+
+    // Set initially selected cells
+    for (auto it = selected.constBegin(); it != selected.constEnd(); ++it) {
+        const QPoint &cell = *it;
+        selectionModel.select(model.index(cell.y(), cell.x()), QItemSelectionModel::Select);
+    }
+
+    tableView->setModel(QVariant::fromValue(&model));
+    tableView->setSelectionModel(&selectionModel);
+
+    WAIT_UNTIL_POLISHED;
+
+    // Check that all delegates have "selected" set with the initial value
+    for (auto fxItem : tableViewPrivate->loadedItems) {
+        const auto context = qmlContext(fxItem->item.data());
+        const int row = context->contextProperty("row").toInt();
+        const int column = context->contextProperty("column").toInt();
+        const bool selected = fxItem->item->property("selected").toBool();
+        const auto modelIndex = model.index(row, column);
+        QCOMPARE(selected, selectionModel.isSelected(modelIndex));
+    }
+
+    // Toggle selected on one of the model indices, and check
+    // that the "selected" property got updated as well
+    const QModelIndex toggleIndex = model.index(toggle.y(), toggle.x());
+    const bool wasSelected = selectionModel.isSelected(toggleIndex);
+    selectionModel.select(toggleIndex, QItemSelectionModel::Toggle);
+    const auto fxItem = tableViewPrivate->loadedTableItem(toggle);
+    const bool isSelected = fxItem->item->property("selected").toBool();
+    QCOMPARE(isSelected, !wasSelected);
+}
+
+void tst_QQuickTableView::checkSelectionModelWithUnrequiredSelectedProperty()
+{
+    // Check that if there is a property "selected" in the delegate, but it's
+    // not required, then TableView will not touch it. This is for legacy reasons, to
+    // not break applications written before Qt 6.2 that has such a property
+    // added for application logic.
+    LOAD_TABLEVIEW("tableviewwithselected2.qml");
+
+    TestModel model(10, 10);
+    tableView->setModel(QVariant::fromValue(&model));
+    QItemSelectionModel *selectionModel = tableView->selectionModel();
+    QVERIFY(selectionModel);
+
+    // Select a cell
+    selectionModel->select(model.index(1, 1), QItemSelectionModel::Select);
+
+    WAIT_UNTIL_POLISHED;
+
+    const auto fxItem = tableViewPrivate->loadedTableItem(QPoint(1, 1));
+    const bool selected = fxItem->item->property("selected").toBool();
+    QCOMPARE(selected, false);
+}
+
+void tst_QQuickTableView::removeAndAddSelectionModel()
+{
+    // Check that if we remove the selection model from TableView, all delegates
+    // will be unselected. And opposite, if we add the selection model back, the
+    // delegates will be updated.
+    LOAD_TABLEVIEW("tableviewwithselected1.qml");
+
+    TestModel model(10, 10);
+    QItemSelectionModel selectionModel(&model);
+
+    // Select a cell in the selection model
+    selectionModel.select(model.index(1, 1), QItemSelectionModel::Select);
+
+    tableView->setModel(QVariant::fromValue(&model));
+    tableView->setSelectionModel(&selectionModel);
+
+    WAIT_UNTIL_POLISHED;
+
+    // Check that the delegate item is selected
+    const auto fxItem = tableViewPrivate->loadedTableItem(QPoint(1, 1));
+    bool selected = fxItem->item->property("selected").toBool();
+    QCOMPARE(selected, true);
+
+    // Remove the selection model, and check that the delegate item is now unselected
+    tableView->setSelectionModel(nullptr);
+    selected = fxItem->item->property("selected").toBool();
+    QCOMPARE(selected, false);
+
+    // Add the selection model back, and check that the delegate item is selected again
+    tableView->setSelectionModel(&selectionModel);
+    selected = fxItem->item->property("selected").toBool();
+    QCOMPARE(selected, true);
+}
+
 QTEST_MAIN(tst_QQuickTableView)
 
 #include "tst_qquicktableview.moc"