ALS Class: Layer

new Layer(wizardResults, settings)

Base class for all layers for the Layer System.

Basically, it's a wrapper around L.FeatureGroup. It doesn't provide all of it's methods because they're used internally in the layer system, and their usage will break it. So do NOT touch the actual FeatureGroup object.

Every layer has its own menu which you can modify by using methods inherited from L.ALS.Widgetable.

Usage:

Set L.ALS.Layer#defaultName property to the default name of your layer.
Create wizard by extending L.ALS.Wizard.
Set L.ALS.Layer.wizard to an instance of your wizard.
If you need to implement settings for your layer, extend L.ALS.Settings and set L.ALS.Layer.settings to an instance of your settings.
Implement L.ALS.Layer#init method. It's used as a constructor.
Modify layer menu by using methods inherited from L.ALS.Widgetable.
Implement your own methods or extend current ones. Basically, make it work :D

Please, read the docs for each public method, you might need to (if not should) override most of them.

Important notes:

NEVER use L.LayerGroup because it breaks layer system!
Use L.ALS.Layer#addLayers and L.ALS.Layer#removeLayers to add and remove Leaflet layers.
To hide Leaflet layers from the map, use this.map.remove() and this.map.add().
Use L.ALS.Layer#addEventListenerTo and L.ALS.Layer#removeEventListenerFrom to add and remove event listeners from objects and map.
Use L.ALS.ControlManager methods to manage controls.
Unless your layer is super simple, you'll most likely need to implement custom serialization and deserialization mechanisms. Please, refer to the L.ALS.Serializable docs and example project for this.

Parameters:

Name	Type	Description
`wizardResults`	Object	Results compiled from the wizard. It is an object who's keys are IDs of your widgets and values are, well, their values.
`settings`	SettingsObject	Current layer settings.

Mixes In:

L.ALS.ControlManager

Extends

L.ALS.Widgetable

Members

<static> settings :L.ALS.Settings

Settings instance

Type:

L.ALS.Settings

<static> wizard :function

Wizard class which gives a layer its initial properties

Type:

function

<protected> constructorArguments :Array.<any>

Contains arguments passed to this constructor

Type:

Array.<any>

Inherited From:

L.ALS.Serializable#constructorArguments

container :HTMLDivElement

Container to add widgets to. This element must be added to the page.

Type:

HTMLDivElement

Inherited From:

L.ALS.Widgetable#container

creationCancelled

Whether creation of this layer has been cancelled at L.ALS.Layer#init by calling cancelCreation().

<readonly> defaultName :string

Name to be assigned to this layer by default. Set it to locale property to localize it.

Type:

string

<readonly> id :string

Unique ID of this layer

Type:

string

<readonly> isSelected :boolean

Indicates whether this layer is selected or not. Should not be modified!

Type:

boolean

<readonly> isShown :boolean

Indicates whether this layer is shown or not. Do NOT modify!

Type:

boolean

layerSystem :L.ALS.System

Layer system managing this layer

Type:

L.ALS.System

<protected> map :L.Map

Map on which this layer is being added

Type:

L.Map

pane :string

Pane name for this layer

Type:

string

paneElement :HTMLDivElement

Pane element for this layer

Type:

HTMLDivElement

<protected> serializationIgnoreList :Array.<string>

Contains properties that won't be serialized. Append your properties at the constructor.

Type:

Array.<string>

Inherited From:

L.ALS.Serializable#serializationIgnoreList

writeToHistoryOnInit

Whether ALS should write an entry to the history when this layer is created or duplicated, i.e. when L.ALS.Layer#init is called.

Setting it to false allows you to control when an action should be added to the history. Useful for things like dynamic content loading. You also may want to use L.ALS.operationsWindow to display loading text and animation.

You should always call L.ALS.Layer#writeToHistory when you're done!

You can always change the value of this property back to true to make ALS write to history automatically.

Example

Read file from a wizard asynchronously. Write to the history when file is read.
L.ALS.MyLayer = L.ALS.Layer.extend({
    writeToHistoryOnInit: false, // Disable writing to the history on initialization

    init: function (wizardResults, settings) {
         // Read a file from a wizard
         let file = wizardResults["fileWidget"][0], fileReader = new FileReader();
         fileReader.addEventListener("load", (event) => {
             // File reading logic here...

             writeToHistory(); // File is read, time to write layer creation to the history
         });
    }
});

Methods

<static> deserialize()

See:

L.ALS.Serializable.deserialize

<static> deserializeImportantProperties(serialized, instance)

Deserializes some important properties. Must be called at deserialize in any layer!

Parameters:

Name	Type	Description
`serialized`	Object	Serialized object
`instance`	L.ALS.Layer \| Object	New instance of your layer

<protected> _onDeselect()

Called whenever user deselects this layer.

<protected> _onSelect()

Called whenever user selects this layer.

addEventListenerTo(object, type, handler)

Adds event listener (handler) to the object. Use it instead of object.on().

Note: we use object's methods as handlers to be able to save and restore them when user saves the project.

Parameters:

Name	Type	Description
`object`	Object	Object to add listener to
`type`	string	Event type, string in format used by Leaflet
`handler`	string	Your object's method that will handle this event

addLayers(layers)

Adds Leaflet layers to this layer.

Do NOT override!

Parameters:

Name	Type	Description
`layers`	L.Layer	Layers to add

addWidget(widget)

Adds widget to this widgetable

Parameters:

Name	Type	Description
`widget`	L.ALS.Widgets.BaseWidget	Widget to add

Inherited From:

L.ALS.Widgetable#addWidget

Returns:

This

Type: L.ALS.Widgetable

addWidgets(widgets)

Adds all widgets to this widgetable

Parameters:

Name	Type	Description
`widgets`	L.ALS.Widgets.BaseWidget	Widgets to add

Inherited From:

L.ALS.Widgetable#addWidgets

Returns:

This

Type: L.ALS.Widgetable

applyNewSettings(settings)

Called whenever user updates the settings. Use it to update your layer depending on changed settings.

Parameters:

Name	Type	Description
`settings`	SettingsObject	Same as settings passed to `L.ALS.Layer#init`

<protected> copySettingsToThis(settings)

Copies settings to this layer as properties

Parameters:

Name	Type	Description
`settings`	SettingsObject	`settings` argument passed to `L.ALS.Layer#init`

deleteLayer(shouldAskUser, writeToHistory)

Deletes this layer

Parameters:

Name	Type	Description
`shouldAskUser`	boolean	If set to true, the message asking if user wants to delete selected layer will be displayed. Otherwise, layer will be silently deleted.
`writeToHistory`	boolean	If true, will write deletion to the history

deserializeWidgets(serializedWidgets, seenObjects)

Deserializes widgets and adds them to this object. Removes all previously added widgets. Use this if you want to deserialize only widgets in your own Widgetable.

Parameters:

Name	Type	Description
`serializedWidgets`	Object	Result of `L.ALS.Widgetable#serializeWidgets`
`seenObjects`	Object	Already seen objects' ids. Intended only for internal use.

Inherited From:

L.ALS.Widgetable#deserializeWidgets

eachLayer()

See:

FeatureGroup.eachLayer

Returns:

this

Type: L.ALS.Layer

getBounds()

See:

FeatureGroup.getBounds

getName()

Returns:

Name of this layer

Type: string

getObjectToSerializeTo(newObject, seenObjects)

Registers this object for serialization and deserialization. Returns an object to serialize custom properties to.

Call it first, if you implement your own algrorithm, and serialize to the returned object!

Parameters:

Name	Type	Description
`newObject`	Object	Object to where you'll serialize
`seenObjects`	Object	Already seen objects

Inherited From:

L.ALS.Serializable#getObjectToSerializeTo

Overrides:

L.ALS.Widgetable#getObjectToSerializeTo

Returns:

Object to serialize to.

Type: Object

getWidgetById(id)

Finds widget by ID

Parameters:

Name	Type	Description
`id`	string	ID of a control to find

Inherited From:

L.ALS.Widgetable#getWidgetById

Returns:

Widget with given ID.

Type: L.ALS.Widgets.BaseWidget

init(wizardResults, settings, cancelCreation)

Use this method instead of L.ALS.Layer#initialize

Parameters:

Name	Type	Description
`wizardResults`	Object	Results compiled from the wizard. It is an object who's keys are IDs of your controls and values are values of your controls.
`settings`	SettingsObject	Current layer settings and both default and custom general settings.
`cancelCreation`	function	A function that will safely cancel creation of this layer. If your initialization calls other layer methods, consider using `L.ALS.Layer#creationCancelled` property to detect whether creation has been cancelled and to avoid getting errors. You should call this function only in synchronous code, only at `L.ALS.Layer#init` and only before adding any widgets!

onDelete()

Called upon deletion. Here you can clean up everything you've done which can't be undone by the system (i.e., layers added directly to the map or created elements on the page)

onDeselect()

Called whenever user deselects this layer.

onHide()

Called whenever layer is being hidden

onNameChange()

Called whenever user changes this layer's name

onSelect()

Called whenever user selects this layer.

onShow()

Called whenever layer is being shown

removeAllWidgets()

Removes all widgets from the container

Inherited From:

L.ALS.Widgetable#removeAllWidgets

Returns:

This

Type: L.ALS.Widgetable

removeEventListenerFrom(object, type, handler)

Removes event listener (handler) to the specified event type from the object. Use it instead object.off().

Parameters:

Name	Type	Description
`object`	object	Object to remove event listener from
`type`	string	Event type
`handler`	string	Event listener (handler) to remove

See:

Layer.addEventListenerTo For more information

removeLayers(layers)

Removes added Leaflet layers with its event handlers.

Parameters:

Name	Type	Description
`layers`	L.Layer	Layers to remove. If layer extends LayerGroup, will also remove Leaflet layers contained in it.

removeWidget(id)

Removes widget from the container

Parameters:

Name	Type	Description
`id`	string	ID of a widget to remove

Inherited From:

L.ALS.Widgetable#removeWidget

Returns:

This

Type: L.ALS.Widgetable

serialize(seenObjects)

Serializes this layer.

Default implementation is:

let serialized = L.ALS.Widgetable.prototype.serialize.call(this, seenObjects);
this.serializeImportantProperties(serialized);
return serialized;

Parameters:

Name	Type	Description
`seenObjects`	Object	Already seen objects

Overrides:

L.ALS.Widgetable#serialize

Returns:

Type: Object

serializeConstructorArguments()

Serializes constructor arguments. If your constructor is not empty, result of this method MUST be added to json at L.ALS.Serializable#serialize as "_construtorArgs" property.

Deprecated in favor of L.ALS.Serializable#getObjectFromSerialized which uses this function under-the-hood.

Inherited From:

L.ALS.Serializable#serializeConstructorArguments

Deprecated:

Returns:

Serialized constructor arguments

Type: Array

serializeImportantProperties(serialized)

Serializes some important properties. Must be called at L.ALS.Layer#serialize in any layer!

Deprecated in favor of L.ALS.Serializable.getObjectFromSerialized which uses this function under-the-hood.

Parameters:

Name	Type	Description
`serialized`	Object	Your serialized object

Deprecated:

serializeWidgets(seenObjects)

Serializes widgets.

If you're serializing L.ALS.Layer, you don't need to call this method, L.ALS.Layer#getObjectToSerializeTo already does that.

Parameters:

Name	Type	Description
`seenObjects`	Object	Already seen objects' ids. Intended only for internal use.

Inherited From:

L.ALS.Widgetable#serializeWidgets

Returns:

Object where keys are widget's ids and values are serialized widgets themselves

Type: Object

setConstructorArguments(args)

Sets constructor arguments for serialization

Parameters:

Name	Type	Description
`args`		Arguments to set

Inherited From:

L.ALS.Serializable#setConstructorArguments

setName(name)

Sets name of this layer

Parameters:

Name	Type	Description
`name`	string	Name to set

setStyle()

See:

FeatureGroup.setStyle

Returns:

this

Type: L.ALS.Layer

toGeoJSON()

Called when layer is being exported. If you want to export more than only geometry, override this method.

Default implementation is:

return this._leafletLayers.toGeoJSON();

See:

L.FeatureGroup.toGeoJSON

writeToHistory()

Writes a record to the history. Call it at the end of each action.

This method interferes with serialization and deserialization. It won't do anything, if called when serialization or deserialization hasn't finished, for example, when restoring from history.

Basically, an alias for L.ALS.System#writeToHistory.