setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
setAlignment(Qt::AlignBottom);
setInteractive(true);
+ //setOptimizationFlags(QGraphicsView::DontClipPainter | QGraphicsView::DontAdjustForAntialiasing);
+ // setOptimizationFlags(QGraphicsView::DontAdjustForAntialiasing);
+ setViewportUpdateMode(QGraphicsView::BoundingRectViewportUpdate);
+ setTransformationAnchor(QGraphicsView::NoAnchor);
_scene = new ChatScene(filter, filter->idString(), viewport()->width() - 2, this); // see below: resizeEvent()
- connect(_scene, SIGNAL(sceneHeightChanged(qreal)), this, SLOT(sceneHeightChanged(qreal)));
+ connect(_scene, SIGNAL(sceneRectChanged(const QRectF &)), this, SLOT(sceneRectChanged(const QRectF &)));
+ connect(_scene, SIGNAL(lastLineChanged(QGraphicsItem *, qreal)), this, SLOT(lastLineChanged(QGraphicsItem *, qreal)));
setScene(_scene);
+ // installEventFilter(_scene);
- _lastScrollbarPos = verticalScrollBar()->maximum();
connect(verticalScrollBar(), SIGNAL(valueChanged(int)), this, SLOT(verticalScrollbarChanged(int)));
}
void ChatView::resizeEvent(QResizeEvent *event) {
QGraphicsView::resizeEvent(event);
- scene()->setWidth(viewport()->width() - 2); // FIXME figure out why we have to hardcode the -2 here -> Qt-Bug most probably
+
+ // we can reduce viewport updates if we scroll to the bottom allready at the beginning
+ verticalScrollBar()->setValue(verticalScrollBar()->maximum());
+
+ // FIXME: without the hardcoded -2 Qt reserves space for a horizontal scrollbar even though it's disabled permanently.
+ // this does only occur on QtX11 (at least not on Qt for Mac OS). Seems like a Qt Bug.
+ scene()->updateForViewport(viewport()->width() - 2, viewport()->height());
+
+ _lastScrollbarPos = verticalScrollBar()->maximum();
verticalScrollBar()->setValue(verticalScrollBar()->maximum());
}
-void ChatView::sceneHeightChanged(qreal dh) {
+void ChatView::lastLineChanged(QGraphicsItem *chatLine, qreal offset) {
+ Q_UNUSED(chatLine)
QAbstractSlider *vbar = verticalScrollBar();
Q_ASSERT(vbar);
- if(vbar->maximum() - vbar->value() <= dh + 5) // in case we had scrolled only about half a line to the bottom we allow a grace of 5
+ if(vbar->maximum() - vbar->value() <= offset + 5) { // 5px grace area
vbar->setValue(vbar->maximum());
+ }
}
void ChatView::verticalScrollbarChanged(int newPos) {
QAbstractSlider *vbar = verticalScrollBar();
Q_ASSERT(vbar);
- if(vbar->maximum() - vbar->value() <= 5) // FIXME workaround the fact that the view gets scrolled up a few px on buffer change
- vbar->setValue(vbar->maximum());
-
+ // check for backlog request
if(newPos < _lastScrollbarPos) {
int relativePos = 100;
if(vbar->maximum() - vbar->minimum() != 0)