How do I enable scrolling of a group ?

Scott Rossi scott at tactilemedia.com
Sun Feb 21 18:08:38 CET 2016


Ok, reading your description, I've seen what you're talking about in browsers on iOS -- you can use two finger touch to scroll a text region independently of a web page.  And I believe this works because the control is essentially a field, which is known to the browser to be scrollable, unlike groups in LC which Safari knows nothing about. So my guess would be like your comment, to use rawKeyDown or similar to enable scrolling.

If you haven't already, you could try enabling scrollbars on the group as a test, and see if that enables scrolling, but my guess is a control being a text-containing-field is what tells the OS that the control can be scrolled.

Regards,

Scott Rossi
Creative Director
Tactile Media UX/UI Design

> On Feb 21, 2016, at 5:32 AM, Alex Tweedly <alex at tweedly.net> wrote:
> 
> Thanks to you , and Scott R.
> 
> However, I guess I need to explain myself better .... :-)
> 
> If I have a field which
> - is enabled
> - has a formatted size that exceeds the actual size
> - has scroollbars enabled
> THEN - the field will respond to the user scrolling (in this case by using two finger touch on the trackpad of a Macbook) and swiping / moving their fingers.
> 
> No script needed - it just responds the way a user would expect; it's the default behaviour /operation for a field.
> 
> I would *expect* that a group which meets similar criteria would respond similarly - i.e. without any scripting.
> 
> In the Message watcher, when positioned over a field, I see rawKeyDown, cRevGeneral and scrollbarDrag events
> But when positioned over a group - only the rawKeyDown events fire.
> 
> So - am I just over-optimistic, and it is expected that any group scrolling is not handled by default ?
> 
> Or do I need to process rawKeyDowns (as for a mouse scroll wheel) and do my own scrolling ?
> 
> (Hmmm - just typing this message makes me convinced the answer is that I do my own scrolling in response to rawkeydowns. So thanks for letting me think out loud - but do correct me if I'm wrong :-)
> 
> -- Alex.
> 
>> On 21/02/2016 03:52, [-hh] wrote:
>> This is essentially the same technique that Scott R. suggested.
>> New is the MOVE-TO-SCROLL-FACTOR, in case you prefer that.
>> 
>> ** The scroll respects here the group's relative to card's size. **
>> ** Thus scrolling becomes "parallel" to the mouseMove distances. **
>> For example if you move your fingers/the mouse from (20,70) to (50,30)
>> then the hscroll of the the group changes by +30
>> and the vscroll of the the group changes by -40.
>> Of course you may moreover scale these factors (fw0, fh0 below) to
>> your needs, for example to an increase for a large display.
>> 
>> -- In group's script.
>> -- Here given for hscroll and vscroll, mostly I use only one of both.
>> -- Also I give it for mouseMove, you change this to your need
>> -- (touchMove ...) better than I do.
>> 
>> local d0=false, x0=0, y0=0, h0=0, w0=0, fh0=1, fw0=1
>> 
>> on mouseEnter; put false into d0; end mouseEnter
>> on mouseUp; put false into d0; end mouseUp
>> on mouseRelease; put false into d0; end mouseRelease
>> 
>> on mouseMove x,y
>>   if not d0 then exit mouseMove
>>   set hscroll of me to w0+fw0*(x-x0)
>>   set vscroll of me to h0+fh0*(y-y0)
>> end mouseMove
>> 
>> on mouseDown
>>   put (the height of this card) div (the height of me) into fh0
>>   put (the width of this card) div (the width of me) into fw0
>>   put true into d0; put the clickV into y0; put the clickH into x0
>>   put the vscroll of me into h0 ; put the hscroll of me into w0
>> end mouseDown
>> 
>> I also have sometimes, in order to have a 'static' scrollbar size,
>> a transparent (for example by using ink 'noop") object, may also be
>> disabled, of card's (half) size in the group.
>> 
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