Drawer: respect swipe velocity

A fast enough swipe should open/close the drawer,
even if it doesn't cross the position threshold.

Change-Id: Iede4ec669f7d42d197e8a42623714c977b0c8a03
Reviewed-by: J-P Nurmi <jpnurmi@theqtcompany.com>

2 files changed, 48 insertions, 9 deletions

diff --git a/src/templates/qquickdrawer.cpp b/src/templates/qquickdrawer.cpp
index 7f0ef44c..58fe2d87 100644
--- a/src/templates/qquickdrawer.cpp
+++ b/src/templates/qquickdrawer.cpp
@@ -42,6 +42,7 @@
 #include <QtQuick/private/qquickanimation_p.h>
 #include <QtQuick/private/qquickitemchangelistener_p.h>
 #include <QtQuickTemplates/private/qquickcontrol_p_p.h>
+#include <QtQuickTemplates/private/qquickvelocitycalculator_p_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -110,6 +111,7 @@ public:
     qreal offset;
     qreal position;
     QPointF pressPoint;
+    QQuickVelocityCalculator velocityCalculator;
     QQuickItem *content;
     QQuickPropertyAnimation *animation;
 };
@@ -167,6 +169,8 @@ bool QQuickDrawerPrivate::handleMousePressEvent(QQuickItem *item, QMouseEvent *e
         event->accept();
     }
 
+    velocityCalculator.startMeasuring(pressPoint, event->timestamp());
+
     return item == q;
 }
 
@@ -204,21 +208,20 @@ bool QQuickDrawerPrivate::handleMouseMoveEvent(QQuickItem *item, QMouseEvent *ev
     return q->keepMouseGrab();
 }
 
+static const qreal openCloseVelocityThreshold = 300;
+
 bool QQuickDrawerPrivate::handleMouseReleaseEvent(QQuickItem *item, QMouseEvent *event)
 {
     Q_Q(QQuickDrawer);
     bool wasGrabbed = q->keepMouseGrab();
     if (wasGrabbed) {
-//        int startDragVelocity = QGuiApplication::styleHints()->startDragVelocity();
-//        if (startDragVelocity && QGuiApplicationPrivate::mouseEventCaps(event) & QTouchDevice::Velocity) {
-//            QVector2D velocity = QGuiApplicationPrivate::mouseEventVelocity(event);
-//            qreal vel = (edge == Qt::LeftEdge || edge == Qt::RightEdge) ? velocity.x() : velocity.y();
-//            qDebug() << vel << "vs." << startDragVelocity;
-//        }
-        if (position < 0.3) {
-            q->close();
-        } else if (position > 0.7) {
+        velocityCalculator.stopMeasuring(event->pos(), event->timestamp());
+        const qreal velocity = velocityCalculator.velocity().x();
+
+        if (position > 0.7 || velocity > openCloseVelocityThreshold) {
             q->open();
+        } else if (position < 0.3 || velocity < -openCloseVelocityThreshold) {
+            q->close();
         } else {
             switch (edge) {
             case Qt::LeftEdge:
@@ -465,6 +468,7 @@ void QQuickDrawer::mouseUngrabEvent()
     Q_D(QQuickDrawer);
     QQuickControl::mouseUngrabEvent();
     d->pressPoint = QPoint();
+    d->velocityCalculator.reset();
 }
 
 void QQuickDrawer::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
diff --git a/tests/auto/controls/data/tst_drawer.qml b/tests/auto/controls/data/tst_drawer.qml
index 28db11c8..fff8ec49 100644
--- a/tests/auto/controls/data/tst_drawer.qml
+++ b/tests/auto/controls/data/tst_drawer.qml
@@ -63,4 +63,39 @@ TestCase {
         verify(control.animation)
         control.destroy()
     }
+
+    Component {
+        id: rectDrawer
+
+        Drawer {
+            Rectangle {
+                width: 200
+                height: 400
+                color: "steelblue"
+            }
+        }
+    }
+
+    function test_swipeVelocity() {
+        skip("QTBUG-52003");
+
+        var control = rectDrawer.createObject(testCase)
+        verify(control.contentItem)
+        compare(control.edge, Qt.LeftEdge)
+        compare(control.position, 0.0)
+
+        var dragDistance = Math.max(20, Qt.styleHints.startDragDistance + 5)
+        var distance = dragDistance * 1.1
+        if (distance >= control.width * 0.7)
+            skip("This test requires a startDragDistance that is less than the opening threshold of the drawer")
+
+        mousePress(control, 0, 0, Qt.LeftButton)
+        mouseMove(control, distance, 0, Qt.LeftButton)
+        verify(control.position > 0)
+        tryCompare(control, "position", distance / control.contentItem.width)
+        mouseRelease(control, distance, 0, Qt.LeftButton)
+        tryCompare(control, "position", 1.0)
+
+        control.destroy()
+    }
 }