How to reproduce this bug: 1) Click the left mouse button inside folder view widget and drag through an area. 2) Release the left mouse button, but drag-select does not stop. 3) Click the left mouse button elsewhere in the folder view widget, drag-select still does not stop.
Step 1) of the previous comment is wrong, apologies. correct step 1) click and hold on the folder view widget to drag it to some position. Rest of the steps are correct.
*** Bug 380905 has been marked as a duplicate of this bug. ***
Patch under review at https://phabricator.kde.org/D6246
Git commit fd4d41bd65fd3a3190471476104b0bac9f8ab542 by Eike Hein. Committed on 17/06/2017 at 03:24. Pushed by hein into branch 'master'. Don't rely on QQuickWindow delivering QEvent::Ungrab as mouseUngrabEvent (as it no longer does in Qt 5.8+) Summary: QQuickWindow::sendEvent in Qt 5.7 and older had the following code to deliver QEvent::UngrabMouse by calling QQuickItem::mouseUngrabEvent: case QEvent::UngrabMouse: { QSet<QQuickItem *> hasFiltered; if (!d->sendFilteredMouseEvent(item->parentItem(), item, e, &hasFiltered)) { e->accept(); item->mouseUngrabEvent(); } } This is gone from Qt 5.8+. While QEvent::Ungrab is still delivered to items, QQuickItem::mouseUngrabEvent is only called under constrained circumstances elsewhere, e.g. when ending an actual mouse grab held by an item and tracked by Qt. MouseEventListener relied on mouseUngrabEvent being called to implement something akin to MouseArea::canceled: Signaling a user it should clean up state after a press event, instead of, say, assuming the button is still held and waiting around for a release event. While QEvent::Ungrab was already being intercepted as well, it was only done for event de- duplication, not used for the above. This changes the code so handleUngrab checks first whether we're actually in press state (to make it safe to call repeatedly) and then call it from both the generic event handler and mouseUngrabEvent. This makes it work again with newer Qts. We rely on this particularly in the desktop containment, where we use EventGenerator from this same lib to deliver QEvent::Ungrab to applets when the containment goes into applet move mode on press-and-hold. Without MouseEventListener emiting canceled in response, e.g. moving a Folder View applet will e.g. put it into rectangle selection mode unwanted. Reviewers: #plasma Subscribers: plasma-devel, #frameworks Tags: #plasma, #frameworks Differential Revision: https://phabricator.kde.org/D6246 M +7 -4 src/qmlcontrols/kquickcontrolsaddons/mouseeventlistener.cpp https://commits.kde.org/kdeclarative/fd4d41bd65fd3a3190471476104b0bac9f8ab542