#1187 Scintilla: Updating scrollbars

[Gintaras Q]

Need an API to update scrollbars.

    case SCI_UPDATESCROLLBARS:
        SetScrollBars();
        break;

Because now vertical scrollbar becomes incorrect after adding, changing or removing annotations. Updating scrollbars for each added/removed/changed annotation would be slow, but I would update asynchronically, eg using a 10 ms timer.

[Neil Hodgson]

Not changing the scrollbars when annotations are added or removed is a bug. It hasn't been visible is SciTE as other operations performed at the same time (such as defining the annotation styles) caused scrollbars to be updated.

Could be fixed with

diff -r 66b002a821f7 src/Editor.cxx
--- a/src/Editor.cxx    Mon May 08 10:40:59 2017 +1000
+++ b/src/Editor.cxx    Wed May 10 08:53:27 2017 +1000
@@ -2638,7 +2638,9 @@
        if (mh.modificationType & SC_MOD_CHANGEANNOTATION) {
            Sci::Line lineDoc = pdoc->LineFromPosition(mh.position);
            if (vs.annotationVisible) {
-               cs.SetHeight(lineDoc, cs.GetHeight(lineDoc) + mh.annotationLinesAdded);
+               if (cs.SetHeight(lineDoc, cs.GetHeight(lineDoc) + mh.annotationLinesAdded)) {
+                   SetScrollBars();
+               }
                Redraw();
            }
        }

Asynchronous scroll bar changes may improve performance in this and other situations but it is possible that this would cause bugs with stale scrollbars.

[Gintaras Q]

I applied the fix. Now SCI_ANNOTATIONSETTEXT works well. Itself it is many times slower now (when annotations are visible), but the async workaround was even slower. No problem. For max speed I can temporarily hide annotations (SCI_ANNOTATIONSETVISIBLE) when there are many annotations to add/remove/modify.

It seems that SCI_ANNOTATIONSETVISIBLE also has this problem. I added SetScrollBars(); in SetAnnotationVisible and now it works well.

[Neil Hodgson]

Committed a fix as [61adfb].