From 4d7b912ca1890b5b0b3ed29568b7091a7e7baef0 Mon Sep 17 00:00:00 2001 From: Guillaume Munch Date: Fri, 29 Jul 2016 21:27:13 +0100 Subject: [PATCH] Fix "scroll here" feature of scrollbar (#10311) Prevent setRange() from causing a recursive call to scrollTo(). Reduces three calls of scrollTo() to one call for all scrolling functions of the scroll bar (e.g. clicking on the arrow, dragging, or clicking somewhere on the scrollbar). --- src/BufferView.cpp | 6 ++++++ src/frontends/qt4/GuiWorkArea.cpp | 7 +++---- 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/src/BufferView.cpp b/src/BufferView.cpp index 900114384f..0212b165d1 100644 --- a/src/BufferView.cpp +++ b/src/BufferView.cpp @@ -564,6 +564,12 @@ void BufferView::updateScrollbar() d->scrollbarParameters_.max -= minVisiblePart(); else d->scrollbarParameters_.max -= d->scrollbarParameters_.page_step; + + // 0 must be inside the range as it denotes the current position + if (d->scrollbarParameters_.max < 0) + d->scrollbarParameters_.max = 0; + if (d->scrollbarParameters_.min > 0) + d->scrollbarParameters_.min = 0; } diff --git a/src/frontends/qt4/GuiWorkArea.cpp b/src/frontends/qt4/GuiWorkArea.cpp index 9223964e42..75afebfd02 100644 --- a/src/frontends/qt4/GuiWorkArea.cpp +++ b/src/frontends/qt4/GuiWorkArea.cpp @@ -671,10 +671,9 @@ void GuiWorkArea::toggleCursor() void GuiWorkArea::Private::updateScrollbar() { ScrollbarParameters const & scroll_ = buffer_view_->scrollbarParameters(); - // WARNING: don't touch at the scrollbar value like this: - // verticalScrollBar()->setValue(scroll_.position); - // because this would cause a recursive signal/slot calling with - // GuiWorkArea::scrollTo + // Block signals to prevent setRange() and setSliderPosition from causing + // recursive calls via the signal valueChanged. (#10311) + QSignalBlocker blocker(p->verticalScrollBar()); p->verticalScrollBar()->setRange(scroll_.min, scroll_.max); p->verticalScrollBar()->setPageStep(scroll_.page_step); p->verticalScrollBar()->setSingleStep(scroll_.single_step); -- 2.39.2