BrickContext

Softcoded application context

Contexts have parents and children, they represent the lifecycle of bricks. They contain callbacks executed at specific time of the brick lifespan.

Each time a brick is updated with new inputs, Context.clear is called, executing all callbacks registered with Context.onClear.

When a brick is destroyed, Context.destroy is called, executing all callbacks registered with Context.onClear and Context.onDestroy

Extends

• Context

Constructors

Constructor

new BrickContext(): BrickContext;

Returns

BrickContext

Inherited from

Context.constructor

Methods

clear()

clear(): void;

Clear the current context: detach and destroys all children context. The context can be reused.

Returns

void

Inherited from

Context.clear

---

createChild()

createChild(debugName?): BrickContext;

Create and return a new context, child of the current one. Mainly used to run other bricks within the current one (e.g.: the iterator of the brick For Each).

Parameters

Parameter	Type	Description
debugName?	string	a name to give to the context for debugging purpose.

Returns

BrickContext

---

destroy()

destroy(): void;

Destroy the current context. It destroys all children context attached to this one and clear their values. The context cannot be reused after calling this function.

Returns

void

Inherited from

Context.destroy

---

get()

get<T>(key, global?): T;

Return the current value of the specified property. If there is currently no value, return null.

Type Parameters

Type Parameter
T

Parameters

Parameter	Type	Description
key	string | Property<T>	the property or key string
global?	boolean	whether the method checks parent contexts (Default = false)

Returns

T

the current value

---

getClosest()

getClosest(selector): BrickContext;

Return the closest parent of a given type If no context of the specified type is found from the hierarchy, returns the root context.

Parameters

Parameter	Type	Description
selector	{ modelTag: InstanceOrTag; }	the context selector
selector.modelTag	InstanceOrTag	tag of the "type" of context you want to find in the parent tree

Returns

BrickContext

---

getOtherContext()

getOtherContext(id): BrickContext;

Return the context with the specified id if accessible (in the hierarchy) from this context. Otherwise, return null.

Parameters

Parameter	Type	Description
id	string	the context id we want to retrieve

Returns

BrickContext

---

getParent()

getParent(): BrickContext;

Return the parent context if it exists.

Returns

BrickContext

---

has()

has<T>(key, global?): boolean;

Returns a boolean indicating whether a property has a value or not.

Type Parameters

Type Parameter
T

Parameters

Parameter	Type	Description
key	string | Property<T>	the property or key string
global?	boolean	whether the method checks parent contexts (Default = false)

Returns

boolean

whether property has a value or not

---

isDestroyed()

isDestroyed(): boolean;

Whether the context is destroyed.

Returns

boolean

Inherited from

Context.isDestroyed

---

observe()

observe<T>(
   key, 
   waitForValue?, 
global?): Observable<T>;

Return an observable to subscribe to value updates of the specified property. If waitForValue is set to FALSE (TRUE by default), the first value received by the observable is null if there is no value at subscription time. If global is set to TRUE (FALSE by default), it observes values coming from other contexts accessible from the current one.

Type Parameters

Type Parameter
T

Parameters

Parameter	Type	Description
key	string | Property<T>	the property or key string
waitForValue?	boolean	whether the observable should wait for a first value to get a value. (Default = true)
global?	boolean	whether to listen to a value coming from other contexts. (Default = false)

Returns

Observable<T>

the observable

---

offClear()

offClear(id): void;

Remove a previously registered callback with Context.onClear method using its id.

Parameters

Parameter	Type	Description
id	string	the id of the callback to unregister

Returns

void

Inherited from

Context.offClear

---

offDestroy()

offDestroy(callbackId): boolean;

Remove a previously registered callback with Context.onDestroy method using its id.

Parameters

Parameter	Type	Description
callbackId	string	the id of the callback to unregister

Returns

boolean

Inherited from

Context.offDestroy

---

onClear()

onClear(callback): string;

Register a callback to execute every time the context is cleared. This happens every time the brick is refreshed with new inputs and during the brick destruction. Return the callback id.

Parameters

Parameter	Type	Description
callback	() => void	the callback function

Returns

string

the callback id

Inherited from

Context.onClear

---

onContext()

onContext(id, callback): () => void;

Listen to the creation of the context with the specified id. Executes the callback when that context becomes accessible by this current context. Return a function to unregister the listener.

Parameters

Parameter	Type	Description
id	string	the context id, which corresponds to the tag of the brick to be retrieved.
callback	(context) => void	the function to execute when the specified brick context is available

Returns

(): void;

Returns

void

---

onDestroy()

onDestroy(callback): string;

Register a callback to execute when the context is destroyed. Return the callback id.

Parameters

Parameter	Type	Description
callback	() => void	the callback function

Returns

string

the callback id

Inherited from

Context.onDestroy

---

remove()

remove<T>(key): boolean;

Clear the value of the specified property and propagate that event.

Type Parameters

Type Parameter
T

Parameters

Parameter	Type	Description
key	string | Property<T>	the property or key string

Returns

boolean

---

repeat()

repeat<T>(key, observable): this;

Subscribe to the specified observable and set its values to the context with the provided key.

Type Parameters

Type Parameter
T

Parameters

Parameter	Type	Description
key	string | Property<T>	the key used to set the values coming from the observable
observable	Observable<T>	the observable providing values

Returns

this

this context

---

runner()

runner<T>(key): BrickContext;

Run a runnable property and returns its context.

Type Parameters

Type Parameter
T

Parameters

Parameter	Type	Description
key	| string | Property<T> | Brick	the runnable property or the runnable itself

Returns

BrickContext

the child context or null if the runner was not found

---

set()

set<T>(key, value): this;

Set the specified property value and propagate the update to anyone observing it.

Type Parameters

Type Parameter
T

Parameters

Parameter	Type	Description
key	string | Property<T>	the property or key string
value	T	the new value to set

Returns

this

this

---

setParentElement()

setParentElement(parent): this;

Set the parent element for visual brick to be rendered.

Parameters

Parameter	Type	Description
parent	Element	the parent container

Returns

this

this

---

throw()

throw(error): this;

Throw the specified error to this context. The error will be propagated until it finds an error handler.

Parameters

Parameter	Type	Description
error	string | ErrorFlow | Error	the error to throw and propagate in the contexts hierarchy

Returns

this

this context

---

trigger()

trigger<T>(key): this;

Trigger the specified event and propagate the update to anyone observing it.

Type Parameters

Type Parameter
T

Parameters

Parameter	Type	Description
key	string | Property<T>	the event or key event

Returns

this

this

---

waitFor()

waitFor<T>(key, global?): Promise<T>;

Wait for the property to get a new value, wrapped in a promise. The promise is rejected if no value is set to the specified property before the destruction of this BrickContext.

Type Parameters

Type Parameter
T

Parameters

Parameter	Type	Description
key	string | Property<T>	the property
global?	boolean	whether the method checks parent contexts (Default = false)

Returns

Promise<T>

a promise of the next value of property