kde/dolphin
kde/dolphin
1
0
Fork 0
mirror of https://invent.kde.org/system/dolphin synced 2024-07-07 10:51:45 +00:00
Code Issues Projects Releases Wiki Activity

Fix scrolling on hidpi screens

Browse Source 
Scrolling with libinput was unbearably slow.

QScrollBar is much better at scrolling than us, so let it handle it.

REVIEW: 128432
BUG: 357618
This commit is contained in:
Martin T. H. Sandsmark 2016-07-13 00:29:15 +02:00
parent 4fad4405a7
commit f688bcd1f1
3 changed files with 11 additions and 48 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
src/kitemviews/kitemlistcontainer.cpp
View File

@ -185,27 +185,7 @@ void KItemListContainer::wheelEvent(QWheelEvent* event)
KItemListSmoothScroller* smoothScroller = scrollHorizontally ?
m_horizontalSmoothScroller : m_verticalSmoothScroller;
const QScrollBar* scrollBar = smoothScroller->scrollBar();
if (!event->pixelDelta().isNull()) {
const int numPixels = event->pixelDelta().y();
if (event->modifiers().testFlag(Qt::ShiftModifier)) {
const int scrollingDirection = numPixels > 0 ? 1 : -1;
smoothScroller->scrollTo(scrollBar->value() - scrollBar->pageStep() * scrollingDirection);
} else {
smoothScroller->scrollTo(scrollBar->value() - numPixels);
}
} else {
const int numDegrees = event->angleDelta().y() / 8;
const int numSteps = qApp->wheelScrollLines() * numDegrees / 15;
if (event->modifiers().testFlag(Qt::ShiftModifier)) {
const int scrollingDirection = numSteps > 0 ? 1 : -1;
smoothScroller->scrollTo(scrollBar->value() - scrollBar->pageStep() * scrollingDirection);
} else {
smoothScroller->scrollTo(scrollBar->value() - numSteps * scrollBar->pageStep() / 12);
}
}
event->accept();
smoothScroller->handleWheelEvent(event);
}
void KItemListContainer::slotScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)

25
src/kitemviews/private/kitemlistsmoothscroller.cpp
View File

@ -172,8 +172,7 @@ bool KItemListSmoothScroller::eventFilter(QObject* obj, QEvent* event)
break;
case QEvent::Wheel:
handleWheelEvent(static_cast<QWheelEvent*>(event));
return true; // eat event so that QScrollBar does not scroll one step more by itself
return false; // we're the ones sending them
default:
break;
@ -196,25 +195,11 @@ void KItemListSmoothScroller::handleWheelEvent(QWheelEvent* event)
const bool previous = m_smoothScrolling;
m_smoothScrolling = true;
int numPixels;
if (!event->pixelDelta().isNull()) {
numPixels = event->pixelDelta().y();
} else {
const int numDegrees = event->angleDelta().y() / 8;
const int numSteps = qApp->wheelScrollLines() * numDegrees / 15;
numPixels = numSteps * m_scrollBar->pageStep() / 12;
}
int value = m_scrollBar->value();
if (event->modifiers().testFlag(Qt::ShiftModifier)) {
const int scrollingDirection = numPixels > 0 ? 1 : -1;
value -= m_scrollBar->pageStep() * scrollingDirection;
} else {
value -= numPixels;
}
m_scrollBar->setValue(value);
QWheelEvent copy = *event;
QApplication::sendEvent(m_scrollBar, &copy);
event->setAccepted(copy.isAccepted());
m_smoothScrolling = previous;
event->accept();
}

12
src/kitemviews/private/kitemlistsmoothscroller.h
View File

@ -77,6 +77,11 @@ public:
// stable.
bool requestScrollBarUpdate(int newMaximum);
/**
* Forwards wheel events to the scrollbar, ensuring smooth and proper scrolling
*/
void handleWheelEvent(QWheelEvent* event);
protected:
virtual bool eventFilter(QObject* obj, QEvent* event);
@ -84,13 +89,6 @@ private slots:
void slotAnimationStateChanged(QAbstractAnimation::State newState,
QAbstractAnimation::State oldState);
private:
/**
* Results into a smooth-scrolling of the target dependent on the direction
* of the wheel event.
*/
void handleWheelEvent(QWheelEvent* event);
private:
bool m_scrollBarPressed;
bool m_smoothScrolling;