fixed textheight affects scrolling?

[Klaus major-k]

Hi Mark,

> Am 09.07.2020 um 11:22 schrieb Mark Waddingham via use-livecode <use-livecode at lists.runrev.com>:
> 
> On 2020-07-09 09:54, Klaus major-k via use-livecode wrote:
>> Hi all,
>>> Am 08.07.2020 um 17:51 schrieb Klaus major-k via use-livecode <use-livecode at lists.runrev.com>:
>>> Hi friends,
>>> strange phenomenon, maybe I am missing something!?
>>> LC 9.6 on macOS 10.14.6
>>> I have two fields with all available fonts and each line is formatted directly
>>> in the appropriate font it reads.
>>> I set the FixedLineHeight for ONE field to 28, doesn't matter actually.
>>> Now I want to select a specific line in the fields with this script:
>>> -------------------------------
>>> on mouseUp pMouseButton
>>> set the wholematches to TRUE
>>> put lineoffset("Lucida Grande",fld "fonts") into tLine
>>> ## Which is 366 in my fields!
>>> put the effective textheight of fld "fonts" into tTH
>>> set the scroll of fld "fonts" to tLine*tTH + the height of fld "fonts"
>>> set the hilitedlines of fld "fonts" to tLine
>>> end mouseUp
>>> -------------------------------
>>> Works fine for the field WITHOUT fixedlineheigt and selects the line -> Lucida Grande
>>> However the same script used with the field WITH fixedlineheight, it selects -> Lucida Grande Bold
>>> which is the line AFTER "Lucida Grande" and actually line 367!?
>>> What am I overlooking?
>>> Thanks for any hints!
> 
> I suspect the fact it works in the non-fixedline height case is serendipity in this specific case - if line height isn't fixed then each line will have a different height based on the fonts (although most will be the same if the fontSize is the same)...
> LineOffset is 1-based - so the first line has scroll 0ish (ish because of field margins etc.) - that's probably the issue with your existing code.
> There's an easier way I think though which should be independent of any field styling (size, font, wrapping)...
> You can get the formattedTop of a line - which gives you the card-relative y co-ordinate of the top of the including the fields top and scroll. So this should do the trick:
>   set the scroll of field "fonts" to the scroll of field "fonts" + \
>                                      the formattedTop of line tLine of field "fonts" - \
>                                      the top of field "fonts"
> The adjustment is necessary because the scroll value is relative to the top-left of the 'content' of the field.
> 
> Hope this helps!
> 
> Mark.

thank you very much!
But even with this new script LC scrolls to and selects -> Lucida Grande only if "fixedlineheight" is UNchecked!?


Best

Klaus
--
Klaus Major
https://www.major-k.de
klaus at major-k.de