Shrink grid padding to least possible while allowing space for required controls

packages/frontend-core/src/components/grid/layout/Grid.svelte

@@ -26,7 +26,7 @@
     MaxCellRenderOverflow,
     GutterWidth,
     DefaultRowHeight,
-    Padding,
+    VPadding,
     SmallRowHeight,
     ControlsHeight,
     ScrollBarSize,
@@ -119,7 +119,7 @@
   // Derive min height and make available in context
   const minHeight = derived(rowHeight, $height => {
     const heightForControls = showControls ? ControlsHeight : 0
-    return Padding + SmallRowHeight + $height + heightForControls
+    return VPadding + SmallRowHeight + $height + heightForControls
   })
   context = { ...context, minHeight }
 

packages/frontend-core/src/components/grid/layout/NewRow.svelte

@@ -31,6 +31,7 @@
     filter,
     inlineFilters,
     columnRenderMap,
+    scrollTop,
   } = getContext("grid")
 
   let visible = false
@@ -43,6 +44,21 @@
   $: $datasource, (visible = false)
   $: selectedRowCount = Object.values($selectedRows).length
   $: hasNoRows = !$rows.length
+  $: renderedRowCount = $renderedRows.length
+  $: offset = getOffset($hasNextPage, renderedRowCount, $rowHeight, $scrollTop)
+
+  const getOffset = (hasNextPage, rowCount, rowHeight, scrollTop) => {
+    // If we have a next page of data then we aren't truly at the bottom, so we
+    // render the add row component at the top
+    if (hasNextPage) {
+      return 0
+    }
+    offset = rowCount * rowHeight - (scrollTop % rowHeight)
+    if (rowCount !== 0) {
+      offset -= 1
+    }
+    return offset
+  }
 
   const addRow = async () => {
     // Blur the active cell and tick to let final value updates propagate
@@ -85,12 +101,6 @@
       return
     }
 
-    // If we have a next page of data then we aren't truly at the bottom, so we
-    // render the add row component at the top
-    if ($hasNextPage) {
-      offset = 0
-    }
-
     // If we don't have a next page then we're at the bottom and can scroll to
     // the max available offset
     else {
@@ -98,10 +108,6 @@
         ...state,
         top: $maxScrollTop,
       }))
-      offset = $renderedRows.length * $rowHeight - ($maxScrollTop % $rowHeight)
-      if ($renderedRows.length !== 0) {
-        offset -= 1
-      }
     }
 
     // Update state and select initial cell
@@ -312,8 +318,10 @@
     pointer-events: all;
     z-index: 3;
     position: absolute;
-    top: calc(var(--row-height) + var(--offset) + 24px);
+    top: calc(
-    left: 18px;
+      var(--row-height) + var(--offset) + var(--default-row-height) / 2
+    );
+    left: calc(var(--default-row-height) / 2);
   }
   .button-with-keys {
     display: flex;

packages/frontend-core/src/components/grid/lib/constants.js

@@ -1,12 +1,13 @@
-export const Padding = 100
-export const ScrollBarSize = 8
-export const GutterWidth = 72
-export const DefaultColumnWidth = 200
-export const MinColumnWidth = 80
 export const SmallRowHeight = 36
 export const MediumRowHeight = 64
 export const LargeRowHeight = 92
 export const DefaultRowHeight = SmallRowHeight
+export const VPadding = SmallRowHeight * 2
+export const HPadding = 40
+export const ScrollBarSize = 8
+export const GutterWidth = 72
+export const DefaultColumnWidth = 200
+export const MinColumnWidth = 80
 export const NewRowID = "new"
 export const BlankRowID = "blank"
 export const RowPageSize = 100

packages/frontend-core/src/components/grid/stores/scroll.js

@@ -1,6 +1,12 @@
 import { writable, derived, get } from "svelte/store"
 import { tick } from "svelte"
-import { Padding, GutterWidth, FocusedCellMinOffset } from "../lib/constants"
+import {
+  GutterWidth,
+  FocusedCellMinOffset,
+  ScrollBarSize,
+  HPadding,
+  VPadding,
+} from "../lib/constants"
 import { parseCellID } from "../lib/utils"
 
 export const createStores = () => {
@@ -34,28 +40,15 @@ export const deriveStores = context => {
   // Memoize store primitives
   const stickyColumnWidth = derived(stickyColumn, $col => $col?.width || 0, 0)
 
-  // Derive vertical limits
-  const contentHeight = derived(
-    [rows, rowHeight],
-    ([$rows, $rowHeight]) => ($rows.length + 1) * $rowHeight + Padding,
-    0
-  )
-  const maxScrollTop = derived(
-    [height, contentHeight],
-    ([$height, $contentHeight]) => Math.max($contentHeight - $height, 0),
-    0
-  )
-
   // Derive horizontal limits
   const contentWidth = derived(
     [visibleColumns, stickyColumnWidth, buttonColumnWidth],
     ([$visibleColumns, $stickyColumnWidth, $buttonColumnWidth]) => {
-      const space = Math.max(Padding, $buttonColumnWidth - 1)
+      let width = GutterWidth + $buttonColumnWidth + $stickyColumnWidth
-      let width = GutterWidth + space + $stickyColumnWidth
       $visibleColumns.forEach(col => {
         width += col.width
       })
-      return width
+      return width + HPadding
     },
     0
   )
@@ -71,14 +64,6 @@ export const deriveStores = context => {
     },
     0
   )
-
-  // Derive whether to show scrollbars or not
-  const showVScrollbar = derived(
-    [contentHeight, height],
-    ([$contentHeight, $height]) => {
-      return $contentHeight > $height
-    }
-  )
   const showHScrollbar = derived(
     [contentWidth, screenWidth],
     ([$contentWidth, $screenWidth]) => {
@@ -86,6 +71,30 @@ export const deriveStores = context => {
     }
   )
 
+  // Derive vertical limits
+  const contentHeight = derived(
+    [rows, rowHeight, showHScrollbar],
+    ([$rows, $rowHeight, $showHScrollbar]) => {
+      let height = ($rows.length + 1) * $rowHeight + VPadding
+      if ($showHScrollbar) {
+        height += ScrollBarSize * 2
+      }
+      return height
+    },
+    0
+  )
+  const maxScrollTop = derived(
+    [height, contentHeight],
+    ([$height, $contentHeight]) => Math.max($contentHeight - $height, 0),
+    0
+  )
+  const showVScrollbar = derived(
+    [contentHeight, height],
+    ([$contentHeight, $height]) => {
+      return $contentHeight > $height
+    }
+  )
+
   return {
     contentHeight,
     contentWidth,