diff options
| author | Paul Wicking <paul.wicking@qt.io> | 2020-03-06 07:29:12 +0100 |
|---|---|---|
| committer | Paul Wicking <paul.wicking@qt.io> | 2020-03-06 08:12:52 +0100 |
| commit | a2446c0eede445eb40905487b1ba7c689aa8baef (patch) | |
| tree | 8e0ccfa61d7f8a96b4883e4b55f53a0d9bb0c071 /examples/sql | |
| parent | c3ae30085e4047ee7d5a945c36e2055c2de5197d (diff) | |
Doc: Let SQL Drill Down example show correct use of qgraphicsitem_cast
For qgraphicsitem_cast to work correctly with custom items, one must
reimplement the type() function for each custom QGraphicsItem subclass.
Do that in the example code.
Fixes: QTBUG-7357
Change-Id: Ibf221817908355f0347cddfc46747b6955958f5f
Reviewed-by: Andy Shaw <andy.shaw@qt.io>
Diffstat (limited to 'examples/sql')
| -rw-r--r-- | examples/sql/doc/src/drilldown.qdoc | 3 | ||||
| -rw-r--r-- | examples/sql/drilldown/imageitem.h | 3 |
2 files changed, 6 insertions, 0 deletions
diff --git a/examples/sql/doc/src/drilldown.qdoc b/examples/sql/doc/src/drilldown.qdoc index 8beb515a83..a7a9601c26 100644 --- a/examples/sql/doc/src/drilldown.qdoc +++ b/examples/sql/doc/src/drilldown.qdoc @@ -437,6 +437,9 @@ \snippet drilldown/imageitem.h 0 + We declare a \c Type enum value for our custom item and reimplement + \l{QGreaphicsItem::}{type()}. This is done so we can safely use + qgraphicsitem_cast(). In addition, we implement a public \c id() function to be able to identify the associated location and a public \c adjust() function that can be called to ensure that the image item is given the diff --git a/examples/sql/drilldown/imageitem.h b/examples/sql/drilldown/imageitem.h index abb9103c7e..324c847b12 100644 --- a/examples/sql/drilldown/imageitem.h +++ b/examples/sql/drilldown/imageitem.h @@ -60,8 +60,11 @@ class ImageItem : public QObject, public QGraphicsPixmapItem Q_OBJECT public: + enum { Type = UserType + 1 }; + ImageItem(int id, const QPixmap &pixmap, QGraphicsItem *parent = nullptr); + int type() const override { return Type; } void adjust(); int id() const; |