signage.elements.javascript

Interface Layer

Layer

Javascript-to-Player interface representing a layer within a sign, as defined in SignStix Creator. It can be used as follows:

<script type="text/javascript">
// Access a SignStix layer by its name.
var priceLayer = SignStixGraphics.getLayerNamed('Price');

// Modify properties of that layer.
priceLayer.setText('£9.99!');
priceLayer.setFontSize(80);
priceLayer.setFontColour('#00FF00'); // Green

// Tell SignStix to update its graphics accordingly.
SignStixGraphics.updateDisplay();
</script>

Note that when dealing with layer coordinates, the origin (0, 0) is at the top left of the sign.

Function Summary

Functions

Modifier and Type	Function and Description
void	addCarouselImage(String fileRef, String newLayerName) Add an image to the end of the carousel layer's image list.
void	carouselShiftDown() Attempt to decrement this carousel layer's selection index and invoke animations on the carousel's images to reflect that change.
void	carouselShiftUp() Attempt to increment this carousel layer's selection index and invoke animations on the carousel's images which reflect that change.
void	clearCarousel() Remove any images from this carousel layer and set its selection index to 0.
String	getBlockColour() Find the colour of this block layer.
int	getCarouselSelectionIndex() Find the current selection index of this carousel layer.
String	getFontColour() Find the font colour of this text layer.
String	getFontFace() Find the font face name of this text layer.
int	getFontSize() Find the font size of this text layer.
String	getFontWeight() Find the weight of this text layer.
int	getId() Find the ID of this layer.
int	getLeft() Find the basic left coordinate of this layer within the sign.
String	getName() Find the name of this layer, if any.
int	getNumCarouselImages() Find the number of images in this carousel layer's image list.
String	getText() Find the current text in this text layer.
int	getTop() Find the basic top coordinate of this layer within the sign.
boolean	isSelected() Find out if this image layer is in the selected state.
void	setBlockColour(String htmlColour) Set the colour of this block layer to be the argument.
void	setCarouselSelectionIndex(int index) Attempt to set the selection index of this carousel layer, which may cause images to reposition accordingly.
void	setFontColour(String htmlColour) Set the font colour of this text layer to be the argument.
void	setFontFace(String fontName) Set the font face of this text layer to be the argument.
void	setFontSize(int size) Set the font size of this text layer to be the argument.
void	setFontWeight(String weight) Set the weight of this text layer to be the argument.
void	setImageFromFile(String fileRef) Set the image source of this image layer to be a specific file in the associated folder structure.
void	setImageFromLayerNamed(String layerName) Set the image source of this image layer to be the same as that of the argument image layer.
void	setImageFromUrl(String imageUrl, boolean forceNewDownload, String jsFunctionName) Set the image source of this layer to be the image file available at the argument URL.
void	setLeft(int left) Set the basic left coordinate of this layer within the sign.
void	setSelected(boolean selected) Set the selected state of this image layer.
void	setText(String text) Set the text on this layer.
void	setTextFromLayerNamed(String layerName) Set the text on this text layer to be the same as that of the argument text layer.
void	setTop(int top) Set the basic top coordinate of this layer within the sign.

Function Detail

getName

String getName()

Find the name of this layer, if any.

Returns:

the layer's name, or the empty string if it doesn't have a name.

getId

int getId()

Find the ID of this layer.

Returns:

the unique ID of this layer.

getLeft

int getLeft()

Find the basic left coordinate of this layer within the sign.

Returns:

the coordinate of the layer's left-most edge, ignoring any animations.

setLeft

void setLeft(int left)

Set the basic left coordinate of this layer within the sign. This has no effect on any animations.

Parameters:

left - - the new coordinate of the layer's left-most edge.

getTop

int getTop()

Find the basic top coordinate of this layer within the sign.

Returns:

the coordinate of the layer's top-most edge, ignoring any animations.

setTop

void setTop(int top)

Set the basic top coordinate of this layer within the sign. This has no effect on any animations.

Parameters:

top - - the new coordinate of the layer's top-most edge.

setText

void setText(String text)

Set the text on this layer. Note that this will not change the bounding box of the text layer, so a long piece of text may wrap or not be visible.

If the layer is not a text layer, this function will log an error and return.

Call SignStixGraphics.#updateDisplay() for the change to take effect.

Parameters:

text - - the new text to adopt. Must not be null.

getText

String getText()

Find the current text in this text layer.

If the layer is not a text layer, this function will log an error and return null.

Returns:

the current layer text, or null if this is not a text layer.

setFontSize

void setFontSize(int size)

Set the font size of this text layer to be the argument. If this layer is not a text layer, this function will log an error and return.

Parameters:

size - - must be in the range 1 to 10000.

getFontSize

int getFontSize()

Find the font size of this text layer. If this layer is not a text layer, the function will log an error and return 0.

Returns:

the current font size, or 0 if this is not a text layer.

setFontColour

void setFontColour(String htmlColour)

Set the font colour of this text layer to be the argument. If this layer is not a text layer, this function will log an error and return.

Parameters:

htmlColour - - font colour in HTML format e.g. '#FF0000' for red, '#00FF00' for green.

getFontColour

String getFontColour()

Find the font colour of this text layer. If this layer is not a text layer, the function will log an error and return null.

Returns:

the font colour in HTML format, or null if this is not a text layer.

setFontFace

void setFontFace(String fontName)

Set the font face of this text layer to be the argument. This will only succeed if the argument font is already known to the current sign. If this layer is not a text layer, the function will log an error and return.

Parameters:

fontName - - the name of the required font.

getFontFace

String getFontFace()

Find the font face name of this text layer. If the receiving layer is not a text layer, this function will log an error and return the empty string.

Returns:

the current font face.

setFontWeight

void setFontWeight(String weight)

Set the weight of this text layer to be the argument. If this layer is not a text layer, or the weight is not recognised, the function will log an error and return.

Parameters:

weight - - one of {"normal", "bold"}.

getFontWeight

String getFontWeight()

Find the weight of this text layer. If this layer is not a text layer, or the weight is not recognised, the function will log an error and return the empty string.

Returns:

one of {"normal", "bold"}.

setImageFromLayerNamed

void setImageFromLayerNamed(String layerName)

Set the image source of this image layer to be the same as that of the argument image layer. For example, this can be used to populate a template layer with a given image, in response to a touch.

If the receiving layer is not an image layer, or the argument does not identify an image layer, this function will log an error and return.

Call SignStixGraphics.#updateDisplay() for the change to take effect.

Parameters:

layerName - - the name of an image layer.

setImageFromUrl

void setImageFromUrl(String imageUrl,
                   boolean forceNewDownload,
                   String jsFunctionName)

Set the image source of this layer to be the image file available at the argument URL. This will download the image (subject to the rules below) and set it to be the layer's source.

On completion, a callback function will be invoked to indicate success (or otherwise). On success, call SignStixGraphics.#updateDisplay() for the change to take effect.

Reasons for failure may include:

• The receiving layer is not an image layer.
• The imageUrl is not a valid URL.
• The image could not be downloaded.
• The storage usage of the device is already over a threshold so further downloads will not be attempted.

In the case of failure, the details of the problem will be logged, and the success parameter of the callback will be set to false.

Note that if the sign is restarted (e.g. as a result of a content re-deployment, or a device or application restart), the layer will revert to its original image.

Parameters:

imageUrl - - URL of the image file to download (must be a PNG or JPEG file).

forceNewDownload - - when true, this will force a new download even if the file from a previous download for this URL is still available. When false, this will attempt to re-use a previously downloaded file, if there is one available.

jsFunctionName - - the name of a Javascript callback function that will be called on completion. It must take parameters as follows:

1. String layerName - this layer's name.
2. int layerId - this layer's ID.
3. String imageUrl - the URL passed in originally.
4. boolean success - true if the image was successfully downloaded (if appropriate) and incorporated into the layer.

setImageFromFile

void setImageFromFile(String fileRef)

Set the image source of this image layer to be a specific file in the associated folder structure.

If the receiving layer is not an image layer, or the parameter does not resolve to a known file, this function will log an error and return false.

Call SignStixGraphics.#updateDisplay() for the change to take effect.

Parameters:

fileRef - - file reference (produced by SignStixFiles) identifying an image file within the associated folder structure.

setTextFromLayerNamed

void setTextFromLayerNamed(String layerName)

Set the text on this text layer to be the same as that of the argument text layer. For example, this can be used to populate a template layer with some given text content, in response to a touch.

Note that this will not change the bounding box of the text layer, so a long piece of text may wrap or not be visible.

If the receiving layer is not a text layer, or the argument does not identify a text layer, this function will log an error and return.

Call SignStixGraphics.#updateDisplay() for the change to take effect.

Parameters:

layerName -

setBlockColour

void setBlockColour(String htmlColour)

Set the colour of this block layer to be the argument. If this layer is not a block layer, this function will log an error and return.

Parameters:

htmlColour - - block colour in HTML format e.g. '#FF0000' for red, '#00FF00' for green.

getBlockColour

String getBlockColour()

Find the colour of this block layer. If this layer is not a block layer, the function will log an error and return null.

Returns:

the block colour in HTML format, or null if this is not a block layer.

isSelected

boolean isSelected()

Find out if this image layer is in the selected state. If the receiving layer is not an image layer, this function will return false.

Returns:

true if the layer is an image layer and is selected.

setSelected

void setSelected(boolean selected)

Set the selected state of this image layer. If the receiving layer is not an image layer, nothing will happen.

Parameters:

selected -

clearCarousel

void clearCarousel()

Remove any images from this carousel layer and set its selection index to 0.

If the receiving layer is not a carousel layer, this function will log an error and return.

addCarouselImage

void addCarouselImage(String fileRef,
                    String newLayerName)

Add an image to the end of the carousel layer's image list.

If the receiving layer is not a carousel layer, this function will log an error and return.

Parameters:

fileRef - - reference to an image file looked-up via SignStixFiles.

newLayerName - - the layer name to use when a layer is created for this image.

getNumCarouselImages

int getNumCarouselImages()

Find the number of images in this carousel layer's image list.

If the receiving layer is not a carousel layer, this function will log an error and return 0.

Returns:

the number of images available to the carousel.

getCarouselSelectionIndex

int getCarouselSelectionIndex()

Find the current selection index of this carousel layer.

If the receiving layer is not a carousel layer, this function will log an error and return -1.

Returns:

the selection index (from 0).

setCarouselSelectionIndex

void setCarouselSelectionIndex(int index)

Attempt to set the selection index of this carousel layer, which may cause images to reposition accordingly. An error will be logged if the index is outside the allowed range.

If the receiving layer is not a carousel layer, this function will log an error and return -1.

Parameters:

index - - the index in the image list to become selected (from 0 to the number of images).

carouselShiftUp

void carouselShiftUp()

Attempt to increment this carousel layer's selection index and invoke animations on the carousel's images which reflect that change.

If the receiving layer is not a carousel layer, this function will log an error and return false.

carouselShiftDown

void carouselShiftDown()

Attempt to decrement this carousel layer's selection index and invoke animations on the carousel's images to reflect that change.

If the receiving layer is not a carousel layer, this function will log an error and return false.