From eb926dc31f2a3e7fa287889ba478225ed2498a39 Mon Sep 17 00:00:00 2001 From: Friedemann Kleint Date: Fri, 29 May 2015 14:02:03 +0200 Subject: QSwipeGestureRecognizer: Allow for small direction changes. When trying to do a straight right/left/up/down swipe, a minimal change in the other direction caused to the gesture to be canceled. Introduce a threshold for checking such to prevent this. Task-number: QTBUG-46195 Change-Id: I3e199f2ec0c81d23a16073b1f5b8fff004958239 Reviewed-by: Shawn Rutledge --- src/widgets/kernel/qstandardgestures.cpp | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) (limited to 'src') diff --git a/src/widgets/kernel/qstandardgestures.cpp b/src/widgets/kernel/qstandardgestures.cpp index d19e473d18..3d6ae3f322 100644 --- a/src/widgets/kernel/qstandardgestures.cpp +++ b/src/widgets/kernel/qstandardgestures.cpp @@ -334,23 +334,27 @@ QGestureRecognizer::Result QSwipeGestureRecognizer::recognize(QGesture *state, d->swipeAngle = QLineF(p1.startScreenPos(), p1.screenPos()).angle(); static const int MoveThreshold = 50; + static const int directionChangeThreshold = MoveThreshold / 8; if (qAbs(xDistance) > MoveThreshold || qAbs(yDistance) > MoveThreshold) { // measure the distance to check if the direction changed d->lastPositions[0] = p1.screenPos().toPoint(); d->lastPositions[1] = p2.screenPos().toPoint(); d->lastPositions[2] = p3.screenPos().toPoint(); - QSwipeGesture::SwipeDirection horizontal = - xDistance > 0 ? QSwipeGesture::Right : QSwipeGesture::Left; - QSwipeGesture::SwipeDirection vertical = - yDistance > 0 ? QSwipeGesture::Down : QSwipeGesture::Up; - if (d->verticalDirection == QSwipeGesture::NoDirection) + result = QGestureRecognizer::TriggerGesture; + // QTBUG-46195, small changes in direction should not cause the gesture to be canceled. + if (d->verticalDirection == QSwipeGesture::NoDirection || qAbs(yDistance) > directionChangeThreshold) { + const QSwipeGesture::SwipeDirection vertical = yDistance > 0 + ? QSwipeGesture::Down : QSwipeGesture::Up; + if (d->verticalDirection != QSwipeGesture::NoDirection && d->verticalDirection != vertical) + result = QGestureRecognizer::CancelGesture; d->verticalDirection = vertical; - if (d->horizontalDirection == QSwipeGesture::NoDirection) + } + if (d->horizontalDirection == QSwipeGesture::NoDirection || qAbs(xDistance) > directionChangeThreshold) { + const QSwipeGesture::SwipeDirection horizontal = xDistance > 0 + ? QSwipeGesture::Right : QSwipeGesture::Left; + if (d->horizontalDirection != QSwipeGesture::NoDirection && d->horizontalDirection != horizontal) + result = QGestureRecognizer::CancelGesture; d->horizontalDirection = horizontal; - if (d->verticalDirection != vertical || d->horizontalDirection != horizontal) { - result = QGestureRecognizer::CancelGesture; - } else { - result = QGestureRecognizer::TriggerGesture; } } else { if (q->state() != Qt::NoGesture) -- cgit v1.2.3