don't re-calculate values in loops for layouts

ui/layouts/columnslayout.go

@@ -25,8 +25,9 @@ func (c *ColumnsLayout) MinSize(objects []fyne.CanvasObject) fyne.Size {
 		if !objects[i].Visible() {
 			continue
 		}
-		height = fyne.Max(height, objects[i].MinSize().Height)
-		w := objects[i].MinSize().Width
+		s := objects[i].MinSize()
+		height = fyne.Max(height, s.Height)
+		w := s.Width
 		if i < len(c.ColumnWidths) && c.ColumnWidths[i] > w {
 			w = c.ColumnWidths[i]
 		}

ui/layouts/hboxcustompadding.go

@@ -37,6 +37,7 @@ func (v *HboxCustomPadding) Layout(objects []fyne.CanvasObject, size fyne.Size)
 
 	x, y := float32(0), float32(0)
 
+	padding := v.themePad() + v.ExtraPad
 	extra := float32(0)
 	for _, child := range objects {
 		if !child.Visible() {
@@ -46,7 +47,7 @@ func (v *HboxCustomPadding) Layout(objects []fyne.CanvasObject, size fyne.Size)
 		child.Move(fyne.NewPos(x+extra, y))
 		x += width
 		child.Resize(fyne.NewSize(width, size.Height))
-		extra += (v.themePad() + v.ExtraPad)
+		extra += padding
 	}
 }
 

ui/layouts/leftmiddlerightlayout.go

@@ -30,14 +30,15 @@ func (b *LeftMiddleRightLayout) MinSize(objects []fyne.CanvasObject) fyne.Size {
 }
 
 func (b *LeftMiddleRightLayout) Layout(objects []fyne.CanvasObject, size fyne.Size) {
+	pad := theme.Padding()
 	midW := fyne.Max(b.middleWidth, objects[1].MinSize().Width)
-	lrW := (size.Width - midW - theme.Padding()*4) / 2
+	lrW := (size.Width - midW - pad*4) / 2
 	objects[0].Resize(fyne.NewSize(lrW, size.Height))
-	objects[0].Move(fyne.NewPos(theme.Padding(), 0))
+	objects[0].Move(fyne.NewPos(pad, 0))
 	objects[1].Resize(fyne.NewSize(midW, size.Height))
-	objects[1].Move(fyne.NewPos(lrW+theme.Padding()*2, 0))
+	objects[1].Move(fyne.NewPos(lrW+pad*2, 0))
 	if objects[2] != nil {
 		objects[2].Resize(fyne.NewSize(lrW, size.Height))
-		objects[2].Move(fyne.NewPos(lrW+midW+theme.Padding()*3, 0))
+		objects[2].Move(fyne.NewPos(lrW+midW+pad*3, 0))
 	}
 }

ui/layouts/maxpadlayout.go

@@ -26,11 +26,13 @@ func (c *MaxPadLayout) Layout(objects []fyne.CanvasObject, size fyne.Size) {
 	if len(objects) == 0 {
 		return
 	}
+	pos := fyne.NewPos(c.PadLeft, c.PadTop)
+	objSize := fyne.NewSize(size.Width-c.PadLeft-c.PadRight, size.Height-c.PadTop-c.PadBottom)
 	for _, child := range objects {
 		if !child.Visible() {
 			continue
 		}
-		child.Move(fyne.NewPos(c.PadLeft, c.PadTop))
-		child.Resize(fyne.NewSize(size.Width-c.PadLeft-c.PadRight, size.Height-c.PadTop-c.PadBottom))
+		child.Move(pos)
+		child.Resize(objSize)
 	}
 }

ui/layouts/vboxcustompadding.go

@@ -36,6 +36,7 @@ func (v *VboxCustomPadding) Layout(objects []fyne.CanvasObject, size fyne.Size)
 
 	x, y := float32(0), float32(0)
 
+	padding := theme.Padding() + v.ExtraPad
 	extra := float32(0)
 	for _, child := range objects {
 		if !child.Visible() {
@@ -45,6 +46,6 @@ func (v *VboxCustomPadding) Layout(objects []fyne.CanvasObject, size fyne.Size)
 		child.Move(fyne.NewPos(x, y+extra))
 		y += height
 		child.Resize(fyne.NewSize(size.Width, height))
-		extra += (theme.Padding() + v.ExtraPad)
+		extra += padding
 	}
 }