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AlignChild

layout.AlignChild wraps a single component with explicit cross-axis alignment — the per-child counterpart to VBox.WithHAlign / HBox.WithVAlign. Use it when one child in a box needs different alignment from the rest, or when the child component does not expose its own WithHAlign/WithVAlign builder.

Constructor​

func NewAlignChild(child oat.Component, h oat.HAlign, v oat.VAlign) *AlignChild
  • h — oat.HAlignFill, HAlignLeft, HAlignCenter, or HAlignRight
  • v — oat.VAlignFill, VAlignTop, VAlignMiddle, or VAlignBottom

Pass oat.HAlignFill or oat.VAlignFill for the axis you do not want to constrain.

Basic usage​

// Save pinned right, Cancel pinned left — no spacers needed.
vbox := layout.NewVBox(
    layout.NewAlignChild(saveBtn,   oat.HAlignRight, oat.VAlignFill),
    layout.NewAlignChild(cancelBtn, oat.HAlignLeft,  oat.VAlignFill),
)

Priority​

AlignChild takes highest priority in the alignment resolution order:

  1. AlignChild wrapper — wins unconditionally.
  2. Child's own BaseComponent.HAlign / VAlign (if non-fill).
  3. Box-wide default (WithHAlign / WithVAlign on the box).
  4. HAlignFill / VAlignFill fallback.

Scope — direct children only​

Like all alignment, AlignChild is only honoured on the direct child of the distributing box. If you wrap a Border in an AlignChild and place it in an HBox, the HBox reads the AlignChild's VAlign. The inner widget's alignment is irrelevant to the HBox.

Combining with flex​

AlignChild is not a FlexSpacer — it does not claim flex space on its own. Wrap it with AddFlexChild or NewFlexChild when you also need it to participate in flex distribution:

// Flex child that is also right-aligned in its slot:
vbox.AddFlexChild(
    layout.NewAlignChild(headerWidget, oat.HAlignRight, oat.VAlignFill),
    1,
)

// Inline using NewFlexChild:
vbox := layout.NewVBox(
    layout.NewFlexChild(
        layout.NewAlignChild(headerWidget, oat.HAlignRight, oat.VAlignFill),
    ),
    btnRow,
)

Theme and focus propagation​

AlignChild implements oat.Layout via Children(), so theme propagation and focus collection recurse into the wrapped component automatically — exactly like FlexChild.

Examples​

Bottom-aligned status chip in an HBox​

row := layout.NewHBox(
    layout.NewFlexChild(nameText, 1),
    layout.NewAlignChild(statusChip, oat.HAlignFill, oat.VAlignBottom),
)

Centred button row in a VBox​

btnRow := layout.NewHBox(cancelBtn, layout.NewHGap(2), okBtn)

vbox := layout.NewVBox(
    layout.NewFlexChild(contentArea),
    layout.NewAlignChild(btnRow, oat.HAlignCenter, oat.VAlignFill),
)

Mixed alignment in one VBox​

vbox := layout.NewVBox(
    layout.NewAlignChild(widget.NewText("Welcome"), oat.HAlignCenter, oat.VAlignFill),
    layout.NewFlexChild(bodyContent),
    layout.NewAlignChild(widget.NewText("Sign in →"), oat.HAlignRight, oat.VAlignFill),
)