Layout Terminology

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This is the layout behavior specifications for the default set of ASL widgets. Default values are specified using the Common Expression Language (CEL). As such:

  • Arrays are defined as [ 1, 2, 3 ].
  • Dictionaries are defined as { name: value, name2: value2 }


Related Structures

Layout Unit 
Interval Range 

General Layout Attributes

  • Code for the layout attributes can be found in <adobe/layout_attributes.hpp>.
  • Code for the extents can be found in <adobe/extents.hpp>.

Layout Attributes

(default: 0)
The amount of space between the leftmost (or topmost) widget and the end of the left (or top) margin.
(default: true)
Determines whether or not this node actually creates a widget using a platform widget implementation. Examples of noncreating containers are row, column, and overlay. This attribute is not settable from within the layout description.
(default: 10)
The amount of space to be put between multiple children of the container. This value can also contain an array, which will be iterated in turn to determine the spacing between two child widgets. Example: spacing: [ 5, 10, 15 ] will yield a container with 5 pixels between child widget 1 and 2, 10 pixels between child widget 2 and 3, and so forth.
(default: place_leaf)
The placement of a container's children. Options are:
Align the children in a row
Align the children in a column
Align the children in an overlay. An overlay will cause all children to have horizontal and vertical alignments of align_fill. Each child will share the same layout real estate with its siblings. The idea for an container placing its children using place_overlay is so that only one will be visible at a time.
question : What does place_leaf do?
(default: [ 0, 0, 0, 0])
margin is the amount of space from the frame of the container to the children within. The margins of a container can only be encroached upon by the outset of a child widget. A child widget's outset is not allowed to be larger than its container's margin (implying the outset of the child would extend into and possibly beyond the frame of the container.) If the container has no margin, then the outset of the child widgets will propagate to become the outsets of the parent container. If this attribute is specified using a single value (e.g., margin: 20) it implies the value should be used for all the container's margins.
(default: align_default)
Specifies horizontal alignment of the widget. Options are:
Forward alignment
align_reverse : Reverse alignment
align_center : Center alignment
align_proportional : Distributes leftover container space equally among widgets with this alignment specified (todo: verify)
align_forward_fill : Distributes leftover container space completely to widgets with this alignment specified (todo: verify)
align_reverse_fill : Distributes leftover container space completely to widgets with this alignment specified (todo: verify)
align_default : question fill me in!
align_fill : same as align_forward_fill
align_left_fill : same as align_forward_fill
align_right_fill : same as align_reverse_fill
align_top_fill : same as align_forward_fill
align_bottom_fill : same as align_reverse_fill
align_left : same as align_forward
align_right : same as align_reverse
align_top : same as align_forward
align_bottom : same as align_reverse
  • vertical
  • child_horizontal
  • child_vertical

Widget Extents

  • outset
  • frame
  • inset
  • guide_set (not settable in the layout description)
  • width (not settable in the layout description)
  • height (not settable in the layout description)

Specific Layout Attributes (by widget)


Leaf Widgets