/***************************************************************************
- * Copyright (C) 2005-2019 by the Quassel Project *
+ * Copyright (C) 2005-2020 by the Quassel Project *
* devel@quassel-irc.org *
* *
* This program is free software; you can redistribute it and/or modify *
connect(verticalScrollBar(), &QAbstractSlider::valueChanged, this, &ChatView::verticalScrollbarChanged);
_lastScrollbarPos = verticalScrollBar()->maximum();
+ // Workaround for the ChatView scrolling up a fair bit when scrollbar becomes visible
+ verticalScrollBar()->installEventFilter(this);
+
connect(Client::networkModel(), &NetworkModel::markerLineSet, this, &ChatView::markerLineSet);
// only connect if client is synched with a core
case Qt::Key_Down:
case Qt::Key_PageUp:
case Qt::Key_PageDown:
- if (!verticalScrollBar()->isVisible()) {
- scene()->requestBacklog();
+ if (requestBacklogForScroll()) {
return true;
}
default:
if (event->type() == QEvent::Wheel
|| (event->type() == QEvent::TouchBegin && ((QTouchEvent*)event)->device()->type() == QTouchDevice::TouchScreen)
|| event->type() == QEvent::TouchUpdate) {
- if (!verticalScrollBar()->isVisible()) {
- scene()->requestBacklog();
+ if (requestBacklogForScroll()) {
return true;
}
}
return QGraphicsView::event(event);
}
+bool ChatView::eventFilter(QObject* watched, QEvent* event)
+{
+ QAbstractSlider* vbar = verticalScrollBar();
+ Q_ASSERT(vbar);
+
+ if (watched != vbar) {
+ // Ignore and pass through all events not featuring the scrollbar
+ return false;
+ }
+ if (event->type() == QEvent::Show) {
+ // FIXME: Workaround for the ChatView scrolling up a fair bit when transitioning from the
+ // vertical scrollbar not being visible, to becoming visible. This happens especially
+ // often when no initial backlog is loaded.
+ if (_backlogRequestedBeforeScrollable) {
+ _backlogRequestedBeforeScrollable = false;
+ vbar->setValue(vbar->maximum());
+ }
+ }
+ // Pass through all events
+ return false;
+}
+
void ChatView::resizeEvent(QResizeEvent* event)
{
// if view is currently scrolled to bottom, we want it that way after resizing
_linesWithCache.remove(line);
}
+bool ChatView::requestBacklogForScroll()
+{
+ if (!verticalScrollBar()->isVisible()) {
+ // Not able to scroll, fetch backlog
+ //
+ // Future improvement: continue fetching backlog in chunks until the scrollbar is visible,
+ // or the beginning of the buffer has been reached.
+ scene()->requestBacklog();
+ _backlogRequestedBeforeScrollable = true;
+ // Backlog has been requested
+ return true;
+ }
+ else {
+ // Scrollbar already visible, no backlog requested
+ return false;
+ }
+}
+
void ChatView::checkChatLineCaches()
{
qreal top = mapToScene(viewport()->rect().topLeft()).y() - 10; // some grace area to avoid premature cleaning