TableContainer is now scrollable

elements/containers/table.go

@@ -263,7 +263,68 @@ func (element *TableContainer) HandleMouseDown (x, y int, button input.Button) {
 		}
 		return
 	}}}
-	
+}
+
+// ScrollContentBounds returns the full content size of the element.
+func (element *TableContainer) ScrollContentBounds () image.Rectangle {
+	return element.contentBounds
+}
+
+// ScrollViewportBounds returns the size and position of the element's
+// viewport relative to ScrollBounds.
+func (element *TableContainer) ScrollViewportBounds () image.Rectangle {
+	bounds := element.Bounds()
+	bounds  = bounds.Sub(bounds.Min).Add(element.scroll)
+	return bounds
+}
+
+// ScrollTo scrolls the viewport to the specified point relative to
+// ScrollBounds.
+func (element *TableContainer) ScrollTo (position image.Point) {
+	if position.Y < 0 {
+		position.Y = 0
+	}
+	maxScrollHeight := element.maxScrollHeight()
+	if position.Y > maxScrollHeight {
+		position.Y = maxScrollHeight
+	}
+	if position.X < 0 {
+		position.X = 0
+	}
+	maxScrollWidth := element.maxScrollWidth()
+	if position.X > maxScrollWidth {
+		position.X = maxScrollWidth
+	}
+	element.scroll = position
+	if element.core.HasImage() && !element.warping {
+		element.redoAll()
+		element.core.DamageAll()
+	}
+}
+
+// OnScrollBoundsChange sets a function to be called when the element's viewport
+// bounds, content bounds, or scroll axes change.
+func (element *TableContainer) OnScrollBoundsChange (callback func ()) {
+	element.onScrollBoundsChange = callback
+}
+
+// ScrollAxes returns the supported axes for scrolling.
+func (element *TableContainer) ScrollAxes () (horizontal, vertical bool) {
+	return true, true
+}
+
+func (element *TableContainer) maxScrollHeight () (height int) {
+	viewportHeight := element.Bounds().Dy()
+	height = element.contentBounds.Dy() - viewportHeight
+	if height < 0 { height = 0 }
+	return
+}
+
+func (element *TableContainer) maxScrollWidth () (width int) {
+	viewportWidth := element.Bounds().Dx()
+	width = element.contentBounds.Dx() - viewportWidth
+	if width < 0 { width = 0 }
+	return
 }
 
 func (element *TableContainer) hook (child tomo.Element) {
@@ -326,9 +387,17 @@ func (element *TableContainer) redoAll () {
 		element.updateMinimumSize()
 		return
 	}
+	
+	maxScrollHeight := element.maxScrollHeight()
+	if element.scroll.Y > maxScrollHeight {
+		element.scroll.Y = maxScrollHeight
+	}
+	maxScrollWidth := element.maxScrollWidth()
+	if element.scroll.X > maxScrollWidth {
+		element.scroll.X = maxScrollWidth
+	}
 
 	// calculate the minimum size of each column and row
-	bounds := element.Bounds()
 	var minWidth, minHeight float64
 	columnWidths := make([]float64, element.columns)
 	rowHeights   := make([]float64, element.rows)