IconButtonStandard_Stylesheet.yaml

A standard icon button: a low-emphasis action shown as an icon alone.

The look of IconButtonStandard (in Icon buttons). How component stylesheets work.

The stylesheet

# IconButtonStandard: the look of each part of the component, by the part's id.
# A value in {{ }} is one of the component's parameters.
styles:
  - id: root
    style:
      width: "{{ size }}"
      height: "{{ size }}"
      align_content: center
      background: transparent
      corner_radius: "{{ corner_radius }}"
  - id: icon
    style:
      width: 24
      height: 24
      foreground: on_surface_variant

How it is tied to the component

IconButtonStandard_Component.yaml holds the structure: the parts, each with an id. This file holds the look: each rule's id names a part, and its style is what that part looks like. When a view uses component: IconButtonStandard, Tesserae fills in the parameters (a value like "{{ width }}" becomes the width the view passed), picks a branch of any if:, and puts each rule under the style the part already has, so a part's own style: always wins.

The parts

root (Rect)

Field	Value	What it does
width	the size parameter	Pixels, auto (its content's size, or stretched), or a percentage of the parent such as 50%.
height	the size parameter	Pixels, auto (its content's size, or stretched), or a percentage of the parent such as 50%.
align_content	center	Where its children sit: top_left, top, top_right, left, center, right, bottom_left, bottom or bottom_right. Not set, they fill the space across the layout.
background	transparent	Its fill: a theme role such as surface, #RRGGBB, any CSS colour, or a gradient such as linear-gradient(90deg, primary, tertiary).
corner_radius	the corner_radius parameter	Pixels, or a shape token (none to extra_large, or full for a pill or circle). Per corner: a list [top_left, top_right, bottom_right, bottom_left], or a mapping of corners and edges (top, right, bottom, left) with the rest square.

icon (Icon)

Field	Value	What it does
width	24	Pixels, auto (its content's size, or stretched), or a percentage of the parent such as 50%.
height	24	Pixels, auto (its content's size, or stretched), or a percentage of the parent such as 50%.
foreground	on_surface_variant	Its text or glyph colour: a theme role, #RRGGBB, any CSS colour, or a gradient.

What it makes

With icon: home, size: 40, corner_radius: 20, each part's style is:

root: {width: 40, height: 40, align_content: center, background: transparent, corner_radius: 20}
icon: {width: 24, height: 24, foreground: on_surface_variant}

Changing it

Put a IconButtonStandard_Stylesheet.yaml next to your views. Its rules go over this file's, field by field:

styles:
  - id: root
    style: {background: tertiary}