Maps API for JavaScript Developer's Guide

H.map.provider.TileProvider

Class Summary

Extends: H.map.provider.Provider

TileProvider is an abstract class to provide tile data.

[ For full details, see the Class Details ]

Property Summary

Table 1. Properties
Properties

requestTile : {}

This method requests data for a tile.

cancelTile : {}

This method cancels a tile request, using the caller-supplied tile coordinates.

cancelTileByKey : {}

This method cancels a tile request, using a tile key.

tileSize : {number}

This property holds the size of a tile representing edge length in pixels. Its value must be 2^n where n is in range [0 ... 30], default is 256.

uri : {string}

This property holds the provider's unique resource identifier. If it is not provided at construction time, it defaults to provider's uid.

min : {number}

This property holds a value indicating the minimum zoom level at which the given provider can serve data. The value is set at construction time.

max : {number}

This property holds a value indicating the maximum zoom level at which the given provider can server data. The value is set at construction time.

uid : {string}

This property holds the unique identifier for the provider instance. The value is generated at construction time.

Method Summary

Table 2. Methods
Methods

protected createTileInternal (x, y, z, data, opt_options) : {H.map.provider.Tile}

This method creates a tile object on the basis of the caller-supplied parameters.

getTileKey (x, y, z) : {string}

This method creates a tile key consisting of the provider's URI, and the x, y and z coordinates of the tile, seperated by underscores, for example "4711_7_42_23"

getCopyrights (bounds, level) : {?Array<H.map.ICopyright>}

This method retrieves the copyrights for the provided content for a certain geographical area and zoom level.

providesSpatials () : {boolean}

This method checks whether this provider currently provides spatial map objects. A concrete implementation of Provider must override it if it currently provides Spatials.

providesOverlays () : {boolean}

This method checks whether this provider currently provides overlay map objects. A concrete implementation of Provider must override it if it currently provides overlays.

providesMarkers () : {boolean}

This method checks whether this provider currently provides Marker map objects. A concrete implementation of Provider must override it if it currently provides Markers.

providesDomMarkers () : {boolean}

This method checks whether this provider currentky provides DomMarker map objects. A concrete implementation of Provider must override it if it currently provides Markers.

addEventListener (type, handler, opt_capture, opt_scope)

This method adds a listener for a specific event.

removeEventListener (type, handler, opt_capture, opt_scope)

This method removes a previously added listener from the EventTarget instance.

dispatchEvent (evt)

This method dispatches an event on the EventTarget object.

dispose ()

This method removes listeners from the given object. Classes that extend EventTarget may need to override this method in order to remove references to DOM Elements and additional listeners.

addOnDisposeCallback (callback, opt_scope)

This method adds a callback which is triggered when the EventTarget object is being disposed.

Events Summary

Table 3. Events
Events

update : {H.util.Event}

Event fired when this provider's data updates.

Class Description

TileProvider is an abstract class to provide tile data.

Constructor Details

H.map.provider.TileProvider(options)

Parameters:
 
options:
{H.map.provider.TileProvider.Options}
 
The options to instantiate the given TileProvider

Property Details

requestTile: {}

This method requests data for a tile.

cancelTile: {}

This method cancels a tile request, using the caller-supplied tile coordinates.

cancelTileByKey: {}

This method cancels a tile request, using a tile key.

tileSize: {number}

This property holds the size of a tile representing edge length in pixels. Its value must be 2^n where n is in range [0 ... 30], default is 256.

uri: {string}

This property holds the provider's unique resource identifier. If it is not provided at construction time, it defaults to provider's uid.

min: {number}

This property holds a value indicating the minimum zoom level at which the given provider can serve data. The value is set at construction time.

max: {number}

This property holds a value indicating the maximum zoom level at which the given provider can server data. The value is set at construction time.

uid: {string}

This property holds the unique identifier for the provider instance. The value is generated at construction time.

Method Details

protected createTileInternal (x, y, z, data, opt_options) : {H.map.provider.Tile}

This method creates a tile object on the basis of the caller-supplied parameters.

Parameters:
 
x:
{number}
 
The x tile coordinate (row)
y:
{number}
 
The y tile coordinate (column)
z:
{number}
 
The tile zoom level
data:
{(HTMLImageElement | HTMLCanvasElement)}
 
An object containing the data for the tile
opt_options:
{Object<string, *>=} [optional]
 
An object containing initialization options to be used in tile-specific rendering
Returns:
 
{H.map.provider.Tile}
An object representing the newly created tile

getTileKey (x, y, z) : {string}

This method creates a tile key consisting of the provider's URI, and the x, y and z coordinates of the tile, seperated by underscores, for example "4711_7_42_23"

Parameters:
 
x:
{number}
 
The x tile coordinate (column)
y:
{number}
 
The y tile coordinate (row)
z:
{number}
 
The tile zoom level
Returns:
 
{string}
A string containing the tile key

getCopyrights (bounds, level) : {?Array<H.map.ICopyright>}

This method retrieves the copyrights for the provided content for a certain geographical area and zoom level.

Note: This function may be overridden by H.map.provider.Provider.Options.getCopyrights property. The default implementation returns null.

Parameters:
 
bounds:
{H.geo.Rect}
 
The bounding area for which to retrieve the copyright information
level:
{number}
 
The zoom level for which to retrieve the copyright information
Returns:
 
{?Array<H.map.ICopyright>}
A list of copyright information objects for the provided area and zoom level

providesSpatials () : {boolean}

This method checks whether this provider currently provides spatial map objects. A concrete implementation of Provider must override it if it currently provides Spatials.

Returns:
 
{boolean}
A value indicating whether the provider provides map objects (true) or not (false)

providesOverlays () : {boolean}

This method checks whether this provider currently provides overlay map objects. A concrete implementation of Provider must override it if it currently provides overlays.

Returns:
 
{boolean}
true if the provider provides overlays, otherwse false

providesMarkers () : {boolean}

This method checks whether this provider currently provides Marker map objects. A concrete implementation of Provider must override it if it currently provides Markers.

Returns:
 
{boolean}
A value indicating if the given provider provides Markers (true) or not (false)

providesDomMarkers () : {boolean}

This method checks whether this provider currentky provides DomMarker map objects. A concrete implementation of Provider must override it if it currently provides Markers.

Returns:
 
{boolean}
A value indicating if the given provider provides Markers (true) or not (false)

addEventListener (type, handler, opt_capture, opt_scope)

This method adds a listener for a specific event.

Note that to prevent potential memory leaks, you must either call removeEventListener or dispose on the given object when you no longer need it.

Parameters:
 
type:
{string}
 
The name of the event
handler:
{!Function}
 
An event handler function
opt_capture:
{boolean=} [optional]
 
true indicates that the method should listen in the capture phase (bubble otherwise)
opt_scope:
{Object=} [optional]
 
An object defining the scope for the handler function

removeEventListener (type, handler, opt_capture, opt_scope)

This method removes a previously added listener from the EventTarget instance.

Parameters:
 
type:
{string}
 
The name of the event
handler:
{!Function}
 
A previously added event handler
opt_capture:
{boolean=} [optional]
 
true indicates that the method should listen in the capture phase (bubble otherwise)
opt_scope:
{Object=} [optional]
 
An oject defining the scope for the handler function

dispatchEvent (evt)

This method dispatches an event on the EventTarget object.

Parameters:
 
evt:
{(H.util.Event | string)}
 
An object representing the event or a string with the event name

dispose ()

This method removes listeners from the given object. Classes that extend EventTarget may need to override this method in order to remove references to DOM Elements and additional listeners.

addOnDisposeCallback (callback, opt_scope)

This method adds a callback which is triggered when the EventTarget object is being disposed.

Parameters:
 
callback:
{!Function}
 
The callback function.
opt_scope:
{Object=} [optional]
 
An optional scope for the callback function

Event Details

update: {H.util.Event}

Event fired when this provider's data updates.