Fix locking order so we update UI before running user code in List/Table

Fix #3487

widget/list.go

@@ -572,8 +572,8 @@ func (l *listLayout) updateList(refresh bool) {
 	l.list.propertyLock.Lock()
 	visibleRowHeights, offY, minRow, maxRow := l.list.visibleItemHeights(l.list.itemMin.Height, length)
 	l.list.propertyLock.Unlock()
-	l.renderLock.Unlock()                          // user code should not be locked
 	if len(visibleRowHeights) == 0 && length > 0 { // we can't show anything until we have some dimensions
+		l.renderLock.Unlock()                      // user code should not be locked
 		return
 	}
 
@@ -589,24 +589,16 @@ func (l *listLayout) updateList(refresh bool) {
 				continue
 			}
 			c.Resize(size)
-			l.setupListItem(c, row)
 		}
 
 		c.Move(fyne.NewPos(0, y))
-		if refresh {
-			c.Resize(size)
-			if ok { // refresh visible
-				l.setupListItem(c, row)
-			}
-		}
+		c.Resize(size)
 
 		y += itemHeight + separatorThickness
 		visible[row] = c
 		cells = append(cells, c)
 	}
 
-	l.renderLock.Lock()
-	defer l.renderLock.Unlock()
 	l.visible = visible
 
 	for id, old := range wasVisible {
@@ -621,6 +613,13 @@ func (l *listLayout) updateList(refresh bool) {
 	objects := l.children
 	objects = append(objects, l.separators...)
 	l.list.scroller.Content.(*fyne.Container).Objects = objects
+	l.renderLock.Unlock()  // user code should not be locked
+
+	if refresh {
+		for row, obj := range visible {
+			l.setupListItem(obj, row)
+		}
+	}
 }
 
 func (l *listLayout) updateSeparators() {

widget/table.go

@@ -723,7 +723,6 @@ func (r *tableCellsRenderer) MinSize() fyne.Size {
 
 func (r *tableCellsRenderer) Refresh() {
 	r.cells.propertyLock.Lock()
-	defer r.cells.propertyLock.Unlock()
 	oldSize := r.cells.cellSize
 	r.cells.cellSize = r.cells.t.templateSize()
 	if oldSize != r.cells.cellSize { // theme changed probably
@@ -737,10 +736,12 @@ func (r *tableCellsRenderer) Refresh() {
 	}
 	visibleColWidths, offX, minCol, maxCol := r.cells.t.visibleColumnWidths(r.cells.cellSize.Width, dataCols)
 	if len(visibleColWidths) == 0 { // we can't show anything until we have some dimensions
+		r.cells.propertyLock.Unlock()
 		return
 	}
 	visibleRowHeights, offY, minRow, maxRow := r.cells.t.visibleRowHeights(r.cells.cellSize.Height, dataRows)
 	if len(visibleRowHeights) == 0 { // we can't show anything until we have some dimensions
+		r.cells.propertyLock.Unlock()
 		return
 	}
 
@@ -773,9 +774,6 @@ func (r *tableCellsRenderer) Refresh() {
 			c.Move(fyne.NewPos(cellXOffset, cellYOffset))
 			c.Resize(fyne.NewSize(colWidth, rowHeight))
 
-			if updateCell != nil {
-				updateCell(TableCellID{row, col}, c)
-			}
 			r.visible[id] = c
 			cells = append(cells, c)
 			cellXOffset += colWidth + separatorThickness
@@ -788,7 +786,15 @@ func (r *tableCellsRenderer) Refresh() {
 			r.pool.Release(old)
 		}
 	}
+	visible := r.visible
+	r.cells.propertyLock.Unlock()
 	r.SetObjects(cells)
+
+	if updateCell != nil {
+		for id, cell := range visible {
+			updateCell(TableCellID{id.Row, id.Col}, cell)
+		}
+	}
 }
 
 func (r *tableCellsRenderer) returnAllToPool() {