QQuickTableView: add new 'syncView' property

This property can be set to point to another TableView.
If set, this TableView will be synchronized to the
other table with respect to flicking, column width, row
heights, spacing, etc. This logic is needed as a foundation
for the upcoming HeaderView.

Upcoming patches will implement this logic (together with
autotests) gradually.

Change-Id: Ic7dea8e1d1aa46bbb3ea6e795953a65c96c25cc6
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

4 files changed, 96 insertions, 0 deletions

diff --git a/src/quick/items/qquickitemsmodule.cpp b/src/quick/items/qquickitemsmodule.cpp
index cd5cca5ac9..a6dce33f45 100644
--- a/src/quick/items/qquickitemsmodule.cpp
+++ b/src/quick/items/qquickitemsmodule.cpp
@@ -475,6 +475,9 @@ static void qt_quickitems_defineModule(const char *uri, int major, int minor)
     qmlRegisterUncreatableType<QQuickItemView, 13>(uri, 2, 13, itemViewName, itemViewMessage);
     qmlRegisterType<QQuickPathView, 13>(uri, 2, 13, "PathView");
     qmlRegisterType<QQuickGridView, 13>(uri, 2, 13, "GridView");
+#if QT_CONFIG(quick_tableview)
+    qmlRegisterType<QQuickTableView, 14>(uri, 2, 14, "TableView");
+#endif
 }
 
 static void initResources()
diff --git a/src/quick/items/qquicktableview.cpp b/src/quick/items/qquicktableview.cpp
index 1dca5bea4a..fc7516ec66 100644
--- a/src/quick/items/qquicktableview.cpp
+++ b/src/quick/items/qquicktableview.cpp
@@ -1855,9 +1855,14 @@ void QQuickTableViewPrivate::syncWithPendingChanges()
     // such assignments into effect until we're in a state that allows it.
     Q_Q(QQuickTableView);
     viewportRect = QRectF(q->contentX(), q->contentY(), q->width(), q->height());
+
+    // Sync rebuild options first, in case we schedule a rebuild from one of the
+    // other sync calls above. If so, we need to start a new rebuild from the top.
     syncRebuildOptions();
+
     syncModel();
     syncDelegate();
+    syncSyncView();
 }
 
 void QQuickTableViewPrivate::syncRebuildOptions()
@@ -1922,6 +1927,41 @@ void QQuickTableViewPrivate::syncModel()
     connectToModel();
 }
 
+void QQuickTableViewPrivate::syncSyncView()
+{
+    Q_Q(QQuickTableView);
+
+    if (assignedSyncView != syncView) {
+        if (syncView)
+            syncView->d_func()->syncChildren.removeOne(q);
+
+        if (assignedSyncView) {
+            QQuickTableView *view = assignedSyncView;
+
+            while (view) {
+                if (view == q) {
+                    if (!layoutWarningIssued) {
+                        layoutWarningIssued = true;
+                        qmlWarning(q) << "TableView: recursive syncView connection detected!";
+                    }
+                    syncView = nullptr;
+                    return;
+                }
+                view = view->d_func()->syncView;
+            }
+
+            assignedSyncView->d_func()->syncChildren.append(q);
+            scheduledRebuildOptions |= RebuildOption::ViewportOnly;
+            q->polish();
+        }
+
+        syncView = assignedSyncView;
+    }
+
+    syncHorizontally = syncView && assignedSyncDirection & Qt::Horizontal;
+    syncVertically = syncView && assignedSyncDirection & Qt::Vertical;
+}
+
 void QQuickTableViewPrivate::connectToModel()
 {
     Q_TABLEVIEW_ASSERT(model, "");
@@ -2214,6 +2254,41 @@ void QQuickTableView::setContentHeight(qreal height)
     QQuickFlickable::setContentHeight(height);
 }
 
+QQuickTableView *QQuickTableView::syncView() const
+{
+   return d_func()->assignedSyncView;
+}
+
+void QQuickTableView::setSyncView(QQuickTableView *view)
+{
+    Q_D(QQuickTableView);
+    if (d->assignedSyncView == view)
+        return;
+
+    d->assignedSyncView = view;
+    d->scheduleRebuildTable(QQuickTableViewPrivate::RebuildOption::ViewportOnly);
+
+    emit syncViewChanged();
+}
+
+Qt::Orientations QQuickTableView::syncDirection() const
+{
+   return d_func()->assignedSyncDirection;
+}
+
+void QQuickTableView::setSyncDirection(Qt::Orientations direction)
+{
+    Q_D(QQuickTableView);
+    if (d->assignedSyncDirection == direction)
+        return;
+
+    d->assignedSyncDirection = direction;
+    if (d->assignedSyncView)
+        d->scheduleRebuildTable(QQuickTableViewPrivate::RebuildOption::ViewportOnly);
+
+    emit syncDirectionChanged();
+}
+
 void QQuickTableView::forceLayout()
 {
     d_func()->forceLayout();
diff --git a/src/quick/items/qquicktableview_p.h b/src/quick/items/qquicktableview_p.h
index f32c71b983..3d46221574 100644
--- a/src/quick/items/qquicktableview_p.h
+++ b/src/quick/items/qquicktableview_p.h
@@ -79,6 +79,8 @@ class Q_QUICK_PRIVATE_EXPORT QQuickTableView : public QQuickFlickable
     Q_PROPERTY(bool reuseItems READ reuseItems WRITE setReuseItems NOTIFY reuseItemsChanged)
     Q_PROPERTY(qreal contentWidth READ contentWidth WRITE setContentWidth NOTIFY contentWidthChanged)
     Q_PROPERTY(qreal contentHeight READ contentHeight WRITE setContentHeight NOTIFY contentHeightChanged)
+    Q_PROPERTY(QQuickTableView *syncView READ syncView WRITE setSyncView NOTIFY syncViewChanged REVISION 14)
+    Q_PROPERTY(Qt::Orientations syncDirection READ syncDirection WRITE setSyncDirection NOTIFY syncDirectionChanged REVISION 14)
 
 public:
     QQuickTableView(QQuickItem *parent = nullptr);
@@ -110,6 +112,12 @@ public:
     void setContentWidth(qreal width);
     void setContentHeight(qreal height);
 
+    QQuickTableView *syncView() const;
+    void setSyncView(QQuickTableView *view);
+
+    Qt::Orientations syncDirection() const;
+    void setSyncDirection(Qt::Orientations direction);
+
     Q_INVOKABLE void forceLayout();
 
     static QQuickTableViewAttached *qmlAttachedProperties(QObject *);
@@ -124,6 +132,8 @@ Q_SIGNALS:
     void modelChanged();
     void delegateChanged();
     void reuseItemsChanged();
+    Q_REVISION(14) void syncViewChanged();
+    Q_REVISION(14) void syncDirectionChanged();
 
 protected:
     void geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry) override;
diff --git a/src/quick/items/qquicktableview_p_p.h b/src/quick/items/qquicktableview_p_p.h
index 6bbfd4e2d6..c018356efa 100644
--- a/src/quick/items/qquicktableview_p_p.h
+++ b/src/quick/items/qquicktableview_p_p.h
@@ -249,6 +249,8 @@ public:
     bool blockItemCreatedCallback = false;
     bool layoutWarningIssued = false;
     bool polishing = false;
+    bool syncVertically = false;
+    bool syncHorizontally = false;
 
     QJSValue rowHeightProvider;
     QJSValue columnWidthProvider;
@@ -271,6 +273,11 @@ public:
 
     QSizeF averageEdgeSize;
 
+    QPointer<QQuickTableView> assignedSyncView;
+    QPointer<QQuickTableView> syncView;
+    QList<QPointer<QQuickTableView> > syncChildren;
+    Qt::Orientations assignedSyncDirection = Qt::Horizontal | Qt::Vertical;
+
     const static QPoint kLeft;
     const static QPoint kRight;
     const static QPoint kUp;
@@ -369,6 +376,7 @@ public:
     inline void syncDelegate();
     inline void syncModel();
     inline void syncRebuildOptions();
+    inline void syncSyncView();
 
     void connectToModel();
     void disconnectFromModel();