# Class: LabelJson<T> (/jsdoc/pixi-vn-json/index/classes/LabelJson)



Defined in: [src/interpreter/LabelJson.ts:53](https://github.com/DRincs-Productions/pixi-vn-json/blob/336c45bc1f677c3b088aac058f0a457afc7cf32e/src/interpreter/LabelJson.ts#L53)

A label whose steps are defined by a plain JSON structure ([PixiVNJsonLabelStep](/jsdoc/pixi-vn-json/index/type-aliases/PixiVNJsonLabelStep)\[]).

`LabelJson` bridges pixi-vn's label system and the JSON script format: each step is
lazily converted to a StepLabelType closure that resolves dialogues, choices,
operations, and conditional overrides at runtime via [JsonUnifier](/jsdoc/pixi-vn-json/core/classes/JsonUnifier).

Extends [#extends]

* `LabelAbstract`\<`LabelJson`\<`T`>, `T`>

Type Parameters [#type-parameters]

T [#t]

`T` *extends* `object` = `object`

The type of the props object passed between steps.

Constructors [#constructors]

Constructor [#constructor]

\> **new LabelJson**\<`T`>(`id`, `steps`, `props?`, `options?`): `LabelJson`\<`T`>

Defined in: [src/interpreter/LabelJson.ts:59](https://github.com/DRincs-Productions/pixi-vn-json/blob/336c45bc1f677c3b088aac058f0a457afc7cf32e/src/interpreter/LabelJson.ts#L59)

Parameters [#parameters]

id [#id]

`string`

is the id of the label

steps [#steps]

([`PixiVNJsonLabelStep`](/jsdoc/pixi-vn-json/index/type-aliases/PixiVNJsonLabelStep) | (() => [`PixiVNJsonLabelStep`](/jsdoc/pixi-vn-json/index/type-aliases/PixiVNJsonLabelStep)))\[]

is the list of steps that the label will perform

props? [#props]

`LabelProps`\<`LabelJson`\<`T`>, `number`>

is the properties of the label

options? [#options]

`LabelJsonOptions` = `{}`

Returns [#returns]

`LabelJson`\<`T`>

Overrides [#overrides]

`LabelAbstract<LabelJson<T>, T>.constructor`

Properties [#properties]

id [#id-1]

\> `readonly` **id**: `string`

Defined in: node\_modules/@drincs/pixi-vn/dist/narration.d.ts:81

Get the id of the label. This variable is used in the system to get the label by id, RegisteredLabels.get

Inherited from [#inherited-from]

`LabelAbstract.id`

Accessors [#accessors]

onLoadingLabel [#onloadinglabel]

Get Signature [#get-signature]

\> **get** **onLoadingLabel**(): ((`stepId`, `label`) => `void` | `Promise`\<`void`>) | `undefined`

Defined in: node\_modules/@drincs/pixi-vn/dist/narration.d.ts:101

Is a function that will be executed in [onStepStart](#onstepstart) if the id of the step is 0
and when the user laods a save file.
When you load a save file, will be executed all onLoadingLabel functions of the narration.openedLabels.
It is useful for example to make sure all images used have been cached

Example [#example]

```ts
newLabel("id", [], {
    onLoadingLabel: async (stepId, label) => {
        await Assets.load('path/to/image1.png')
        await Assets.load('path/to/image2.png')
    }
})
```

Returns [#returns-1]

((`stepId`, `label`) => `void` | `Promise`\<`void`>) | `undefined`

Inherited from [#inherited-from-1]

`LabelAbstract.onLoadingLabel`

***

onStepEnd [#onstepend]

Get Signature [#get-signature-1]

\> **get** **onStepEnd**(): ((`stepId`, `label`) => `void` | `Promise`\<`void`>) | `undefined`

Defined in: node\_modules/@drincs/pixi-vn/dist/narration.d.ts:103

A function executed after each `step`. See more \<DynamicLink href="/start/labels-advanced#onstepend">here</DynamicLink>.

Example [#example-1]

```ts
const startLabel = newLabel("start", [
    async () => {
        await showImage("image1", "path/to/image1.png")
        await showImage("image2", "path/to/image2.png")
    }
], {
    onLoadingLabel: async (stepIndex, label) => {
        await Assets.load("path/to/image1.png")
        await Assets.load("path/to/image2.png")
    }
})
```

Returns [#returns-2]

((`stepId`, `label`) => `void` | `Promise`\<`void`>) | `undefined`

Inherited from [#inherited-from-2]

`LabelAbstract.onStepEnd`

***

onStepStart [#onstepstart]

Get Signature [#get-signature-2]

\> **get** **onStepStart**(): ((`stepId`, `label`) => `void` | `Promise`\<`void`>) | `undefined`

Defined in: node\_modules/@drincs/pixi-vn/dist/narration.d.ts:99

A function executed before each `step`.

Example [#example-2]

```ts
const startLabel = newLabel("start", [
    () => {
        narration.dialogue = "Step 1"
    },
    () => {
        narration.dialogue = "Step 2"
    }
], {
    onStepStart: (stepIndex, label) => {
        console.log(`Step ${stepIndex} started`)
    }
})
```

Returns [#returns-3]

((`stepId`, `label`) => `void` | `Promise`\<`void`>) | `undefined`

Inherited from [#inherited-from-3]

`LabelAbstract.onStepStart`

***

stepCount [#stepcount]

Get Signature [#get-signature-3]

\> **get** **stepCount**(): `number`

Defined in: [src/interpreter/LabelJson.ts:106](https://github.com/DRincs-Productions/pixi-vn-json/blob/336c45bc1f677c3b088aac058f0a457afc7cf32e/src/interpreter/LabelJson.ts#L106)

Get the number of steps in the label. This variable is used in the system to get the number of steps in the label.

Returns [#returns-4]

`number`

The number of steps in the label

Overrides [#overrides-1]

`LabelAbstract.stepCount`

***

steps [#steps-1]

Get Signature [#get-signature-4]

\> **get** **steps**(): `StepLabelType`\<`T`>\[]

Defined in: [src/interpreter/LabelJson.ts:101](https://github.com/DRincs-Productions/pixi-vn-json/blob/336c45bc1f677c3b088aac058f0a457afc7cf32e/src/interpreter/LabelJson.ts#L101)

Returns [#returns-5]

`StepLabelType`\<`T`>\[]

Methods [#methods]

getStepById() [#getstepbyid]

\> **getStepById**(`stepId`): `StepLabelType`\<`T`> | `undefined`

Defined in: [src/interpreter/LabelJson.ts:109](https://github.com/DRincs-Productions/pixi-vn-json/blob/336c45bc1f677c3b088aac058f0a457afc7cf32e/src/interpreter/LabelJson.ts#L109)

Get the step by id

Parameters [#parameters-1]

stepId [#stepid]

`number`

Id of the step

Returns [#returns-6]

`StepLabelType`\<`T`> | `undefined`

The step or undefined if it does not exist

Overrides [#overrides-2]

`LabelAbstract.getStepById`

***

getStepSha() [#getstepsha]

\> **getStepSha**(`index`): `string` | `undefined`

Defined in: [src/interpreter/LabelJson.ts:131](https://github.com/DRincs-Productions/pixi-vn-json/blob/336c45bc1f677c3b088aac058f0a457afc7cf32e/src/interpreter/LabelJson.ts#L131)

Returns the SHA-1 hash of the raw step at the given index.
Can be used to detect step changes across label reloads.

Parameters [#parameters-2]

index [#index]

`number`

Zero-based index of the step.

Returns [#returns-7]

`string` | `undefined`

The hex SHA-1 string, or `undefined` if the index is out of range.

Overrides [#overrides-3]

`LabelAbstract.getStepSha`