Element dependencies

The dependency system allows elements to be automatically shown/hidden or enabled/disabled based on the current values of GUI variables — without writing any Python code.

Any element can carry a dependency list in its YAML configuration. After every user interaction, Guitares re-evaluates all dependency rules and updates the GUI accordingly.

Basic structure

- style: pushbutton
  text: Delete
  method: delete_item
  dependency:
  - action: enable
    checkfor: all
    check:
    - variable: selected_index
      operator: ge
      value: 0

This button is only enabled when selected_index >= 0.

Dependency keys

Key	Type	Description
action	str	What to control: `"enable"`, `"visible"`, or `"check"`
checkfor	str	How to combine checks: `"all"`, `"any"`, or `"none"`
check	list	List of individual variable checks (see below)

Check keys

Each entry in the check list compares a variable against a value:

Key	Type	Default	Description
variable	str		Variable name to check
variable_group	str	inherited	Variable group
operator	str		Comparison operator (see table below)
value	any		Value to compare against

Supported operators:

Operator	Meaning
`eq`	Equal to
`ne`	Not equal to
`gt`	Greater than
`ge`	Greater than or equal to
`lt`	Less than
`le`	Less than or equal to

Actions

enable — the element is enabled when the condition is true; disabled otherwise.
visible — the element (and its label) is shown when the condition is true; hidden otherwise.
check — sets the checked state of a checkbox to the condition result.

checkfor logic

all — all checks must be true
any — at least one check must be true
none — no checks must be true (i.e. all checks must be false)

Examples

Enable a button only when at least one item exists in a list:

dependency:
- action: enable
  checkfor: all
  check:
  - variable: nr_items
    operator: gt
    value: 0

Show an extra panel only when a specific scenario is selected:

dependency:
- action: visible
  checkfor: all
  check:
  - variable: scenario
    variable_group: model
    operator: eq
    value: "advanced"

Multiple conditions — enable only when both a file is loaded and a feature is selected:

dependency:
- action: enable
  checkfor: all
  check:
  - variable: file_loaded
    operator: eq
    value: true
  - variable: selected_index
    operator: ge
    value: 0

Enable when either of two conditions holds:

dependency:
- action: enable
  checkfor: any
  check:
  - variable: mode
    operator: eq
    value: "edit"
  - variable: mode
    operator: eq
    value: "draw"

Multiple dependency rules

An element can have multiple dependency entries. All rules are evaluated independently — each controls its own action:

dependency:
- action: enable
  checkfor: all
  check:
  - variable: model_loaded
    operator: eq
    value: true
- action: visible
  checkfor: all
  check:
  - variable: show_advanced
    operator: eq
    value: true