diff --git a/containerbox.go b/containerbox.go index 4c37f92..b4f70b3 100644 --- a/containerbox.go +++ b/containerbox.go @@ -227,12 +227,6 @@ func (this *containerBox) notifyMinimumSizeChange (child anyBox) { } } -func (this *containerBox) boundedLayoutHints () tomo.LayoutHints { - hints := this.layoutHints() - hints.Bounds = this.ContentBounds().Add(this.InnerBounds().Min) - return hints -} - func (this *containerBox) layoutHints () tomo.LayoutHints { return tomo.LayoutHints { OverflowX: this.hOverflow, @@ -247,7 +241,7 @@ func (this *containerBox) contentMinimum () image.Point { minimum := this.box.contentMinimum() if this.layout != nil { layoutMinimum := this.layout.MinimumSize ( - this.boundedLayoutHints(), + this.layoutHints(), this.children) if this.hOverflow { layoutMinimum.X = 0 } if this.vOverflow { layoutMinimum.Y = 0 } @@ -260,8 +254,8 @@ func (this *containerBox) doLayout () { this.box.doLayout() previousContentBounds := this.contentBounds - // by default, use innerBounds for contentBounds. if a direction - // overflows, use the layout's minimum size for it. + // by default, use innerBounds (translated to 0, 0) for contentBounds. + // if a direction overflows, use the layout's minimum size for it. var minimum image.Point if this.layout != nil { minimum = this.layout.MinimumSize ( @@ -269,19 +263,33 @@ func (this *containerBox) doLayout () { this.children) } innerBounds := this.InnerBounds() - this.contentBounds = innerBounds + this.contentBounds = innerBounds.Sub(innerBounds.Min) if this.hOverflow { this.contentBounds.Max.X = this.contentBounds.Min.X + minimum.X } if this.vOverflow { this.contentBounds.Max.Y = this.contentBounds.Min.Y + minimum.Y } - - // offset the content bounds by the scroll so children can be positioned - // accordingly. - this.constrainScroll() - this.contentBounds = this.contentBounds.Add(this.scroll).Sub(innerBounds.Min) // arrange children if this.layout != nil { - this.layout.Arrange(this.boundedLayoutHints(), this.children) + layoutHints := this.layoutHints() + layoutHints.Bounds = this.contentBounds + this.layout.Arrange(layoutHints, this.children) } + + // build an accurate contentBounds by unioning the bounds of all child + // boxes + this.contentBounds = image.Rectangle { } + for _, box := range this.children { + bounds := box.Bounds() + this.contentBounds = this.contentBounds.Union(bounds) + } + + // constrain the scroll + this.constrainScroll() + + // offset children and contentBounds by scroll + for _, box := range this.children { + box.SetBounds(box.Bounds().Add(this.scroll).Add(innerBounds.Min)) + } + this.contentBounds = this.contentBounds.Add(this.scroll) if previousContentBounds != this.contentBounds { this.on.contentBoundsChange.Broadcast()