Scrollbar does not update since 3.20
Submitted by Thomas Martitz
Since 3.20 the scrollbar in Geany does not update (or only erratically). This only affects the editor widget. I bisected a possible commit, see at the end
Perhaps this is specific how the editor widget works w.r.t. to scrolling.
- The editor widget is a ScintillaObject type which is derived from GtkContainer. * The class installs a class handler for "scroll-event" signal.
- Upon instantiation an explicit GtkScrollbar and GtkAdjustment are created
- A handler is connected to the adjustment's "value-changed" signal
The scoll-event handler calls ScrollTo(). That performs a redraw and then calls gtk_adjustment_set_value(). The value-changed handler also calls ScrollTo(). (possible recursion is handled in ScrollTo()).
Debug prints show the GtkAdjustment is properly updated and ScrollTo() is properly called. However, the scrollbar does simply doesn't update.
I bisected the following commits that are candidates:
c1eff2cc] range: deprecate more style propertiespossible first bad commit: [
413b9d5b] range: continue porting to GtkGadgetspossible first bad commit: [
The first one couldn't be tested because it didn't show a scrollbar at all in my scenario. The other one is the first where the bug can be observed. I assume the second one is the problematic one.
 Geany is a text editor and uses Scintilla as the editor component. Most of the code I talked about is here: https://github.com/geany/geany/blob/master/scintilla/gtk/ScintillaGTK.cxx. I tracked this issue for Geany here: https://github.com/geany/geany/issues/1002