ExtendedFabPrimary_Stylesheet.yaml

An extended floating action button in the primary colour: an icon and a label.

The look of ExtendedFabPrimary (in Extended FABs). How component stylesheets work.

The stylesheet

# ExtendedFabPrimary: 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:
      flex_direction: horizontal
      width: "{{ width }}"
      height: 56
      background: primary_container
      corner_radius: large
      elevation: level_3
      padding:
        if: "{{ icon }}"
        then:
          left: 16
          right: 20
          top: 0
          bottom: 0
        else:
          left: 20
          right: 20
          top: 0
          bottom: 0
      align_content:
        if: "{{ icon }}"
        then: left
        else: center
      gap: 8
  - id: icon
    style:
      width: 24
      height: 24
      foreground: on_primary_container
  - id: label
    style:
      foreground: on_primary_container

How it is tied to the component

ExtendedFabPrimary_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: ExtendedFabPrimary, 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 (Container)

Field	Value	What it does
flex_direction	horizontal	How its children are laid out: horizontal (the default) or vertical.
width	the width parameter	Pixels, auto (its content's size, or stretched), or a percentage of the parent such as 50%.
height	56	Pixels, auto (its content's size, or stretched), or a percentage of the parent such as 50%.
background	primary_container	Its fill: a theme role such as surface, #RRGGBB, any CSS colour, or a gradient such as linear-gradient(90deg, primary, tertiary).
corner_radius	large	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.
elevation	level_3	A shadow level, 0 to 5.
padding	left 16, right 20, top 0, bottom 0 if icon, else left 20, right 20, top 0, bottom 0	Space inside it: one number, or {left, right, top, bottom}.
align_content	left if icon, else 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.
gap	8	Space between its children.

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_primary_container	Its text or glyph colour: a theme role, #RRGGBB, any CSS colour, or a gradient.

label (Text)

Field	Value	What it does
foreground	on_primary_container	Its text or glyph colour: a theme role, #RRGGBB, any CSS colour, or a gradient.

What it makes

With label: Go, width: 120, icon: home, each part's style is:

root:
  flex_direction: horizontal
  width: 120
  height: 56
  background: primary_container
  corner_radius: large
  elevation: level_3
  padding: {left: 16, right: 20, top: 0, bottom: 0}
  align_content: left
  gap: 8
icon: {width: 24, height: 24, foreground: on_primary_container}
label: {foreground: on_primary_container}

Changing it

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

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