#include <QScrollBar>
TreeViewTouch::TreeViewTouch(QWidget *parent)
- : QTreeView(parent)
+ : QTreeView(parent)
{
- setAttribute(Qt::WA_AcceptTouchEvents);
+ setAttribute(Qt::WA_AcceptTouchEvents);
}
-
bool TreeViewTouch::event(QEvent *event) {
- if (event->type() == QEvent::TouchBegin) {
- _touchScrollInProgress = true;
- setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
- return true;
- }
+ if (event->type() == QEvent::TouchBegin) {
+ // Register that we may be scrolling, set the scroll mode to scroll-per-pixel
+ // and accept the event (return true) so that we will receive TouchUpdate and TouchEnd/TouchCancel
+ _touchScrollInProgress = true;
+ setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
+ return true;
+ }
- if (event->type() == QEvent::TouchUpdate && _touchScrollInProgress) {
- QTouchEvent::TouchPoint p = ((QTouchEvent*)event)->touchPoints().at(0);
- if (!_firstTouchUpdateHappened) {
- double dx = abs(p.lastPos().x() - p.pos().x());
- double dy = abs(p.lastPos().y() - p.pos().y());
- if (dx > dy) {
- _touchScrollInProgress = false;
- }
- _firstTouchUpdateHappened = true;
- }
- verticalScrollBar()->setValue(verticalScrollBar()->value() - (p.pos().y() - p.lastPos().y()));
- return true;
- }
+ if (event->type() == QEvent::TouchUpdate && _touchScrollInProgress) {
+ QTouchEvent::TouchPoint p = ((QTouchEvent*)event)->touchPoints().at(0);
+ if (!_firstTouchUpdateHappened) {
+ // After the first movement of a Touch-Point, calculate the distance in both axis
+ // and if the point moved more horizontally abort scroll.
+ double dx = abs(p.lastPos().x() - p.pos().x());
+ double dy = abs(p.lastPos().y() - p.pos().y());
+ if (dx > dy) {
+ _touchScrollInProgress = false;
+ }
+ _firstTouchUpdateHappened = true;
+ }
+ // Apply touch movement to scrollbar
+ verticalScrollBar()->setValue(verticalScrollBar()->value() - (p.pos().y() - p.lastPos().y()));
+ return true;
+ }
#if QT_VERSION >= 0x050000
- if (event->type() == QEvent::TouchEnd || event->type() == QEvent::TouchCancel) {
+ if (event->type() == QEvent::TouchEnd || event->type() == QEvent::TouchCancel) {
#else
if (event->type() == QEvent::TouchEnd) {
#endif
- _touchScrollInProgress = false;
- _firstTouchUpdateHappened = false;
- return true;
- }
+ // End scroll and reset variables
+ _touchScrollInProgress = false;
+ _firstTouchUpdateHappened = false;
+ return true;
+ }
- return QTreeView::event(event);
+ return QTreeView::event(event);
}
void TreeViewTouch::mousePressEvent(QMouseEvent * event) {
- if (!_touchScrollInProgress)
- QTreeView::mousePressEvent(event);
+ if (!_touchScrollInProgress)
+ QTreeView::mousePressEvent(event);
}
void TreeViewTouch::mouseMoveEvent(QMouseEvent * event) {
- if (!_touchScrollInProgress)
- QTreeView::mouseMoveEvent(event);
+ if (!_touchScrollInProgress)
+ QTreeView::mouseMoveEvent(event);
};