native scroll for android does not work

Question

I'm trying to create a native Android scroller using the code below. I saved the stack as a standalone app and installed to my Android tablet but the text does not scroll.

local sScrollerID

on preOpenCard
   local tScrollerRect, tContentRect

   // Only create a scroller on a mobile device
   if environment() is not "mobile" then exit preOpenCard

   // Set the area of the scroller
  put the rect of group "scrollArea" into tScrollerRect

   // Set the are of the content to be scrolled
   put the left of field "lorem",the top of field "lorem",the right of field "lorem",the formattedHeight of field "lorem" into tContentRect

   // Create the scroller control
   mobileControlCreate "scroller", "loremScroll"
   put the result into sScrollerID

   // Set the properties of the scroller
   mobileControlSet "loremScroll", "rect", tScrollerRect
   mobileControlSet "loremScroll", "contentRect", tContentRect
   mobileControlSet "loremScroll", "visible", true
   mobileControlSet "loremScroll", "scrollingEnabled", true
   mobileControlSet "loremScroll", "vIndicator", true
   mobileControlSet "loremScroll", "vscroll", 0
end preOpenCard

on closeCard
   // Delete the scroller
   if environment() is not "mobile" then exit closeCard
   mobileControlDelete sScrollerID
end closeCard

on scrollerDidScroll hOffset, vOffset
   // When the user scrolls move the displayed content
   set the vScroll of group "scrollArea" to vOffset
end scrollerDidScroll

How do I correct the script? The stack is here for anyone who needs to see it: native scroll in android.zip

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I also tried to create same kind of scrolling for a group consisting of several text fields and even with the suggestions from Mark (see below) it still does notwork.

the code is here:

local sScrollerID

on openCard
   local tScrollerRect, tContentRect

   // Only create a scroller on a mobile device
   if environment() is not "mobile" then exit openCard

   // Set the area of the scroller
   put the rect of group "scrollArea" into tScrollerRect

   // Set the area of the content to be scrolled
   put the left of group "scrollArea",the top of group "scrollArea",the formattedWidth of group "scrollArea",the formattedHeight of group "scrollArea" into tContentRect


   // Create the scroller control
   mobileControlCreate "scroller", "loremScroll"
   put the result into sScrollerID

   // Set the properties of the scroller
    mobileControlSet "loremScroll", "rect", tScrollerRect
   mobileControlSet "loremScroll", "contentRect", tContentRect
   mobileControlSet "loremScroll", "visible", true
   mobileControlSet "loremScroll", "scrollingEnabled", true
   mobileControlSet "loremScroll", "vIndicator", true
   mobileControlSet "loremScroll", "vscroll", 0
end openCard

on closeCard
   // Delete the scroller
  if environment() is not "mobile" then exit closeCard
   mobileControlDelete sScrollerID
end closeCard

on scrollerDidScroll hOffset, vOffset
   // When the user scrolls move the displayed content
   set the vScroll of group "scrollArea" to vOffset
end scrollerDidScroll

What corrections do I have to make for the group scroll to function? The stack can be downloaded from here: native scroll in android-group.zip

================

3) Now that the scrolling for the group works properly I attempted to create same scrolling for a data grid using this code:

on openCard

      local tScrollerRect, tContentRect

   // Only create a scroller on a mobile device
   if environment() is not "mobile" then exit openCard

   // Set the area of the scroller
   put the rect of group "DataGrid 1" into tScrollerRect

   // Set the area of the content to be scrolled
  put 0,0,(the formattedWidth of group "DataGrid 1"),(the formattedHeight of group "DataGrid 1") into tContentRect

   // Create the scroller control
   mobileControlCreate "scroller", "loremScroll"
   put the result into sScrollerID

   // Set the properties of the scroller
   mobileControlSet "loremScroll", "rect", tScrollerRect
   mobileControlSet "loremScroll", "contentRect", tContentRect
   mobileControlSet "loremScroll", "visible", true
   mobileControlSet "loremScroll", "scrollingEnabled", true
   mobileControlSet "loremScroll", "vIndicator", true
   mobileControlSet "loremScroll", "vscroll", 0

end openCard


on closeCard
   // Delete the scroller
   if environment() is not "mobile" then exit closeCard
   mobileControlDelete sScrollerID
 end closeCard

 on scrollerDidScroll hOffset, vOffset
   // When the user scrolls move the displayed content
   set the vScroll of group "DataGrid 1" to vOffset
 end scrollerDidScroll

But the scrolling of the data grid does not work with this code. What corrections do I have to make? The stack can be downloaded here: DG-android native scroller.zip

Answer 1

You're taking the contectRect of a field and then are trying to scroll a group. Probably you want to scroll the field, so you need to change

on scrollerDidScroll hOffset, vOffset
   // When the user scrolls move the displayed content
   set the vScroll of group "scrollArea" to vOffset
end scrollerDidScroll

into

on scrollerDidScroll hOffset, vOffset
   // When the user scrolls move the displayed content
   set the vScroll of fld "lorem" to vOffset
end scrollerDidScroll

If you really want to scroll the group, then you need to set tContentRect in the preOpenCard handler to the formattedWidth and formattedHeight of the group.