Re: Bug 118418 - Scrolling API?

On Mon, 2019-12-16 at 13:10 +0100, Martin Pieuchot wrote:
> I'm looking for help/explanation about the coordinate system and
> scrolling API to use in `SwAccessibleParagraph'.
>
> I'm currently working on bug #118418 [1], trying to implement
> scrollSubstringTo() and scrollSubstringToPoint() like I did for
> gtk [2] and evince [3].
>
> The diff below clearly shows that I don't know how to translate a
> character index to coordinates that can be feed to Window's Scroll().
>
> So here are my questions:
>
> - Is calling getWindow()'s Scroll() the correct way to realize the
>   scrolling.  If so, the code below doesn't correctly refresh all the
>   text, so what am I missing?
>
> - What API should I use to convert the coordinates?

I don't know for sure the correct answer, but I feel that for writer
ScrollMDI might be your friend here and that the code should look
something like the attached SwAccessibleParagraph::scrollToPosition
demo. I haven't tested or checked further if its the right approach but
maybe that helps.

From a55b4e20faef145f4bb0619bd22a9f78e0a61ca6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Caol=C3=A1n=20McNamara?= <caolanm@redhat.com>
Date: Wed, 22 Jan 2020 17:17:34 +0000
Subject: [PATCH] wip: demo how I think ScrollMDI could be used here

Change-Id: I56ad6a303ef3c9e54ffa3ac506cf206b664831fc
---
 sw/source/core/access/accpara.cxx | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/sw/source/core/access/accpara.cxx b/sw/source/core/access/accpara.cxx
index 0ffeea847e82..678aa2dce64c 100644
--- a/sw/source/core/access/accpara.cxx
+++ b/sw/source/core/access/accpara.cxx
@@ -21,6 +21,7 @@
 #include <numeric>
 #include <txtfrm.hxx>
 #include <flyfrm.hxx>
+#include <mdiexp.hxx>
 #include <ndtxt.hxx>
 #include <pam.hxx>
 #include <unotextrange.hxx>
@@ -2899,9 +2900,14 @@ sal_Int32 SAL_CALL SwAccessibleParagraph::getTextMarkupCount( sal_Int32 
nTextMar
 }
 
 //MSAA Extension Implementation in app  module
-sal_Bool SAL_CALL SwAccessibleParagraph::scrollToPosition( const css::awt::Point&, sal_Bool )
+sal_Bool SAL_CALL SwAccessibleParagraph::scrollToPosition( const css::awt::Point& rPoint, sal_Bool 
)
 {
-    return false;
+    Point aPt(rPoint.X, rPoint.Y);
+    Point aCorePoint(GetMap()->PixelToCore(aPt));
+    const SwRect aRect(aCorePoint, aCorePoint);
+    SwViewShell* pViewShell = GetMap()->GetShell();
+    ScrollMDI(pViewShell, aRect, USHRT_MAX, USHRT_MAX);
+    return true;
 }
 
 sal_Int32 SAL_CALL SwAccessibleParagraph::getSelectedPortionCount(  )
-- 
2.24.1