[[ DataGrid 2 ]] Fix drags to cooperate with the mobile scroller.

Previously, a data grid's mobile scroller was getting in the way of
reorder and swipe actions.

To fix for reordering, we disable the scroller whenn the user clicks
on a reorder control (and re-enable it when the reorder completes).

Swipes are a little trickier. We track dragging on mouse down, but
disabling the scroller at this point will prevent all scrolling.
Instead we attempt to determine if the user is trying to drag the
row before disabling the scroller.

Author: livecodemichael

Toolset/palettes/revdatagridlibrary/behaviorsdatagridbuttonbehavior.livecodescript

@@ -330,7 +330,7 @@ private command _CreateMobileScroller
       mobileControlSet sScrollerId, "canBounce", "true"
       mobileControlSet sScrollerId, "pagingEnabled", "false"
       mobileControlSet sScrollerId, "canScrollToTop", "true"
-      mobileControlSet sScrollerId, "delayTouches", "true"
+      mobileControlSet sScrollerId, "delayTouches", "false"
       mobileControlSet sScrollerId, "canCancelTouches", "true"
       __PollVisibility
    end if
@@ -9593,6 +9593,18 @@ private function __HasMobileScroller
          sScrollerId is among the lines of mobileControls()
 end __HasMobileScroller
 
+command __EnableMobileScroller
+   if __HasMobileScroller() then
+      mobileControlSet sScrollerId, "scrollingEnabled", "true"
+   end if
+end __EnableMobileScroller
+
+command __DisableMobileScroller
+   if __HasMobileScroller() then
+      mobileControlSet sScrollerId, "scrollingEnabled", "false"
+   end if
+end __DisableMobileScroller
+
 --------------------------------------------------------------------------------
 -- DataGrid 2
 --------------------------------------------------------------------------------
@@ -10069,6 +10081,9 @@ command DG2_ReorderStart
       return "Could not find line of control"
    end if
 
+   -- Make sure any scroller doesn't interfere with drag reorders.
+   __DisableMobileScroller
+   
    put tControl into sReorderControl
    put tIndex into sReorderStartIndex
    put tLine into sReorderStartLine
@@ -10192,6 +10207,8 @@ command DG2_ReorderEnd
       return "No reorder currently in progress"
    end if
 
+   __EnableMobileScroller
+   
    -- Animate the control we are reordering into its new slot.
    DG2_AnimationsAdd sReorderControl, "top", the top of sReorderControl, DG2_TopOfControlWithLineNo(sReorderLastHoverLine) + 1, the dgAnimationProp["ReorderHomingDuration"] of me, the dgAnimationProp["ReorderHomingEasing"] of me, "DG2_ReorderControlHomed", empty, the long id of me
    put false into sReorderInProgress
@@ -11091,6 +11108,14 @@ command DG2_AnimationsBatchAddWithArray pAnimationsA
    return tIDs
 end DG2_AnimationsBatchAddWithArray
 
+function DG2_AnimationsGetPendingCount
+   if sAnimationsA is empty or sAnimationsA is not an array then
+      return 0
+   else
+      return the number of lines in the keys of sAnimationsA
+   end if
+end DG2_AnimationsGetPendingCount
+
 -- Set all current animations to their end value.
 command DG2_AnimationsFinaliseAll
    cancel sAnimationsPulseMsgID

Toolset/palettes/revdatagridlibrary/behaviorsrowchainedbehavior.livecodescript

@@ -3,12 +3,18 @@
 -- This behavior sits at the back of a row's behavior chain and is used to
 -- determine and handle edit mode and swipe actions.
 
+local sPreDragging
 local sDragging
 local sDragStart
 local sDragLocs
 local sControlLeft
 local sControlRight
 
+-- A user is seen to be dragging a row if the mouse has moved kPreDragLocDiff
+-- points within kPreDragTimeMargin milliseconds of the initial mouse click.
+constant kPreDragLocDiff = 15
+constant kPreDragTimeMargin = 100
+
 -- A swipe has occured if the mouse has moved kSwipeLocDiff points within
 -- kSwipeTimeDiff milliseconds, plus or minus kSwipeTimeDiffMargin.
 constant kSwipeTimeDiff = 100
@@ -17,16 +23,25 @@ constant kSwipeLocDiff = 50
 
 ----------------------------------------------------------------------
 
-before PreFillInData
+private command DG2_ClearVars
+   put false into sPreDragging
    put false into sDragging
    put empty into sDragStart
    put empty into sDragLocs
    put empty into sControlLeft
    put empty into sControlRight
 
    DG2_CustomisableControlsClearForControl the long id of me
+end DG2_ClearVars
+
+before PreFillInData
+   DG2_ClearVars
 end PreFillInData
 
+before ResetData
+   DG2_ClearVars
+end ResetData
+
 ----------------------------------------------------------------------
 
 before mouseDown
@@ -45,7 +60,11 @@ before mouseDown
          exit to top
       end if
    else
-      if the dgProps["enable swipe"] of the dgControl of me then
+      -- Only track swipes if all previous swipe actions have completed - i.e.
+      -- there are no animations pending. This prevents situations like where a
+      -- user drags in one direction, but an animation is returning the row in
+      -- the oposite direction.
+      if the dgProps["enable swipe"] of the dgControl of me and DG2_AnimationsGetPendingCount() is 0 then
          local tStartDrag
          put false into tStartDrag
 
@@ -69,7 +88,8 @@ before mouseDown
             -- when repositioning the row control under the pointer on drag.
             put item 1 of the mouseLoc into sDragStart
             put the milliseconds && item 1 of the mouseLoc into sDragLocs
-            put true into sDragging
+            put true into sPreDragging
+            put false into sDragging
          end if
 
       end if
@@ -85,6 +105,23 @@ before mouseMove pNewMouseH, pNewMouseV
    end if
 
    if not the dgEditMode of the of the dgControl of me then
+      -- If the user has just clicked (i.e. pre-dragging), attempt to determine
+      -- if the user is trying to drag the row. We do this by checking if the
+      -- horizontal position of the drag has changed sufficiently within a given
+      -- time frame. If so, we can turn the scroller off to prevent any
+      -- interference and begin tracking the drag.
+      if sPreDragging then
+         if abs(word 2 of the last line of sDragLocs - pNewMouseH) > kPreDragLocDiff then
+            put false into sPreDragging
+            put true into sDragging
+            __DisableMobileScroller
+         else if the milliseconds - word 1 of the last line of sDragLocs > kPreDragTimeMargin then
+            put false into sPreDragging
+         else
+            put the milliseconds && pNewMouseH & return before sDragLocs
+         end if
+      end if
+
       if sDragging then
          put the milliseconds && pNewMouseH & return before sDragLocs
 
@@ -146,6 +183,7 @@ before mouseUp
          end if
       end if
    else
+      put false into sPreDragging
       if sDragging then
          DG2_DragFinished
       end if
@@ -163,10 +201,12 @@ before mouseRelease
    if the dgEditMode of the of the dgControl of me then
       DG2_ReorderEnd
    else
+      put false into sPreDragging
       if sDragging then
          DG2_DragFinished
       end if
    end if
+
    pass mouseRelease
 end mouseRelease
 
@@ -211,6 +251,8 @@ end LayoutControl
 ----------------------------------------------------------------------
 
 private command DG2_DragFinished
+   __EnableMobileScroller
+
    local tNow
    put the milliseconds into tNow
 
@@ -252,11 +294,13 @@ private command DG2_DragFinished
       -- Determine the direction of the swipe and make sure we are
       -- currently showing the appropriate control for that swipe direcion.
       if tLocDiff > 0 and the left of me > sControlLeft then
+         put false into sPreDragging
          put false into sDragging
          put empty into sDragLocs
             RowSwipeShowControlForIndexAndSide the dgIndex of me, "left"
             return the result
       else if tLocDiff < 0 and the right of me < sControlRight then
+         put false into sPreDragging
          put false into sDragging
          put empty into sDragLocs
             RowSwipeShowControlForIndexAndSide the dgIndex of me, "right"
@@ -272,6 +316,7 @@ end DG2_DragFinished
 
 command DG2_SwipeReturn pDontAnimate
    -- Return everything back to where it was before the dragging started.
+   put false into sPreDragging
    put false into sDragging
    put empty into sDragLocs
    if  pDontAnimate then