reference

`labkit.app.Definition`

Compile and launch one immutable App SDK contract.

Syntax

app = labkit.app.Definition(Entrypoint=entrypoint, AppId=appId, ...
Title=title, ...
Family=family, AppVersion=version, Updated=date, ...
Requirements=requirements, Workbench=workbench, Name=Value)
fig = app.launch()
fig = app.launch(InitialProject=project)
fig = app.launch(Diagnostics=diagnosticOptions)
requirements = app.launch("requirements")
version = app.launch("version")

Description

Definition validates product metadata, layout-owned callbacks and renderers, global IDs, callback roles, and references in one atomic constructor. The static target graph is cached once. validateViewSnapshot checks a complete view snapshot against that graph without rebuilding the layout.

Required Name-Value Arguments

Entrypoint: Public MATLAB launch function name as a scalar identifier.
AppId: Stable App identifier beginning with an ASCII letter and containing letters, digits, underscore, hyphen, or period.
Title: Nonempty reader-facing scalar text.
Family: Nonempty reader-facing scalar text.
AppVersion: Semantic version in X.Y.Z form.
Updated: Product date in YYYY-MM-DD form.
Requirements: Empty value or labkit.contract.requirements result.
Workbench: Root value returned by labkit.app.layout.workbench.

Optional Name-Value Arguments

DisplayName: Nonempty scalar text. Default: Title.
ProjectSchema: labkit.app.project.Schema or empty for a static App. Default: empty.
CreateSession: Fixed callback session = callback(project,context). Portable project sources remain opaque; use context.resolveSourcePaths while rebuilding transient session data. Default: empty.
PresentWorkbench: Fixed callback view = callback(state). Default: empty.
OnStart: Fixed callback state = callback(state,context), invoked after the first view commit. Default: empty.
BuildDebugSample: Fixed callback pack = callback(context). Default: empty.

Outputs

app: Immutable compiled labkit.app.Definition value.

Definition Methods

launch(): Build and show the native MATLAB App figure.
launch(Diagnostics=options): Use one labkit.app.diagnostic.Options value for standard or verbose sanitized runtime recording.
launch("requirements"): Return declared facade requirements without creating a figure.
launch("version"): Return product version metadata without creating a figure.
validateViewSnapshot(view): Validate target references, target capabilities and complete target coverage. Returns true or throws before any runtime UI mutation.

Errors

labkit:app:contract:UnknownArgument: A required argument is missing or an argument is unknown, duplicated, or unpaired.
labkit:app:contract:InvalidValue: Metadata, requirements, workbench, callbacks, or renderers are malformed.
labkit:app:contract:DuplicateId: A layout ID is duplicated.
labkit:app:contract:UnknownReference: A view target is undeclared.
labkit:app:contract:UnsupportedOperation: A view operation is not legal for its target.
labkit:app:contract:InvalidValue: A launch request or output count is unsupported.

Typical Call

workbench = labkit.app.layout.workbench({ ...
labkit.app.layout.button("run", "Run", @runAnalysis, ...
Tooltip="Compute the current analysis.")});
app = labkit.app.Definition( ...
Entrypoint="labkit_Example_app", AppId="example.app", ...
Title="Example", Family="Examples", AppVersion="1.0.0", ...
Updated="2026-07-19", Requirements=[], Workbench=workbench);

labkit.app.layout.workbench — Assemble controls and a central workspace into the root layout.
labkit.app.view.Snapshot — Build one immutable complete visible-state snapshot.
labkit.contract.requirements — Describe the LabKit API versions required by a caller.
labkit.app.CallbackContext — Provide declared App-neutral runtime capabilities.
labkit.app.diagnostic.Artifact — Describe one anonymous diagnostic-sample artifact.
labkit.app.diagnostic.Options — Configure one App SDK diagnostic session.
labkit.app.diagnostic.SampleContext — Provide bounded folders for anonymous debug samples.
labkit.app.diagnostic.SamplePack — Describe one typed anonymous App reproduction scenario.

Source

This page is generated from the MATLAB help text in +labkit/+app/Definition.m.

labkit.app.Definition