ScrollBar: allow configuring the minimum size

The existing size and position properties cannot be changed,
because then they won't match with Flickable::visibleArea and
we get major problems connecting the two. Thus, the effective
visible position and size are provided as separate properties.

[ChangeLog][Controls][ScrollBar] Added minimumSize, visualSize,
and visualPosition properties.

Task-number: QTBUG-56557
Change-Id: I923a74e5f6db7013b30fc2bef35e3d01282d5d98
Reviewed-by: J-P Nurmi <jpnurmi@qt.io>

1 files changed, 14 insertions, 0 deletions

diff --git a/src/quicktemplates2/qquickscrollbar_p_p.h b/src/quicktemplates2/qquickscrollbar_p_p.h
index 431bb383..384348b4 100644
--- a/src/quicktemplates2/qquickscrollbar_p_p.h
+++ b/src/quicktemplates2/qquickscrollbar_p_p.h
@@ -68,6 +68,17 @@ public:
         return bar->d_func();
     }
 
+    struct VisualArea
+    {
+        VisualArea(qreal pos, qreal sz)
+            : position(pos), size(sz) { }
+        qreal position;
+        qreal size;
+    };
+    VisualArea visualArea() const;
+
+    qreal logicalPosition(qreal position) const;
+
     qreal snapPosition(qreal position) const;
     qreal positionAt(const QPointF &point) const;
     void setInteractive(bool interactive);
@@ -79,10 +90,13 @@ public:
     void handleRelease(const QPointF &point) override;
     void handleUngrab() override;
 
+    void visualAreaChange(const VisualArea &newVisualArea, const VisualArea &oldVisualArea);
+
     qreal size;
     qreal position;
     qreal stepSize;
     qreal offset;
+    qreal minimumSize;
     bool active;
     bool pressed;
     bool moving;