APL Image (APL 1.5)
(This is not the most recent version of APL. Use the Other Versions option to see the documentation for the most recent version of APL)
An Image
component draws a bitmap image on the screen. Don't use animated .gif files in your skills. Although these images may appear animated in the simulator, their behavior on screen devices with Alexa might be different.
Properties
The Image component has the following properties in addition to the base component properties. See the meaning of the columns.
The "auto" value is not supported for dimension-related properties on Image
. If you use "auto", the image might not render.
Property | Type | Default | Styled | Dynamic | Description |
---|---|---|---|---|---|
|
One of: |
|
Yes |
No |
Alignment of the image within the containing box. |
|
Non-negative Absolute dimension |
0 |
Yes |
No |
Clipping radius for the image. |
|
Array of filters |
[ ] |
No |
No |
Filters to apply to the image. |
|
none |
Yes |
Yes |
If set, a theme-appropriate scrim is overlaid on the image. This ensures text placed on the image is legible. | |
|
none |
Yes |
No |
A colored gradient that overlays the image. | |
|
Scale |
|
Yes |
No |
How the image will be resized to fit in the bounding box. |
|
URL or array of URLs |
none |
No |
Yes |
The URL or URLs to download the image from. |
All images must specify a width and a height value. To minimize errors, the width and height of an Image
component default to 100dp.
The source
/ sources
property of the Image
component is an array of one or more image URLs. The Image
component doesn't render until after all of the URLs have been loaded. After all URLs load, the component applies any filters defined in the filters
property. When the filters
property is empty or not provided, the component renders the last image in the sources
array.
Filters modify, augment, and merge images from the image array. The result of filter processing is a single image. The image that results from filter processing can be further modified by the overlayColor
and overlayGradient
properties.
For details about image filters, see Filters.
When the Image
is the source or target of an event, the following values are reported in event.source
or event.target
:
{
// Image-specific values
"type": "Image",
"url": URL, // The URL of the image. Contains an array if multiple images are provided
// General component values
"bind": Map, // Access to component data-binding context
"checked": Boolean, // Checked state
"disabled": Boolean, // Disabled state
"focused": Boolean, // Focused state
"height": Number, // Height of the component, in dp (includes the padding)
"id": ID, // ID of the component
"opacity": Number, // Opacity of the component [0-1]
"pressed": Boolean, // Pressed state
"uid": UID, // Runtime-generated unique ID of the component
"width": Number // Width of the component, in dp (includes the padding)
}
align
Positions the image within the container.
Name | Description |
---|---|
|
Align to the bottom and center horizontally |
|
Align the bottom-left corners |
|
Align the bottom-right corners |
|
Center horizontally and vertically |
|
Align to the left side and center vertically |
|
Align to the right side and center vertically |
|
Align to the top and center horizontally |
|
Align the top-left corners |
|
Align the top-right corners |
borderRadius
A uniform clipping radius to be set on the corners of the image. Setting the borderRadius to a large number will create a circular clip.
filter, filters
One or more filtering operations to apply to the image. See Filters.
overlayColor
A color applied as a scrim across the image. The color must have a transparent component for the image to show. For instance, you could set overlayColor
to rgba(white,0.3)
to overlay the image with white at 30% opacity.
Note that overlayColor
is a convenience name for a filter that overlays the image with a single color. The overlayColor
filter is applied after any filters defined by the filter property.
The scrim applies only to the drawn area of the image, not the padding or any blank space left over after image scaling and alignment.
overlayGradient
A gradient applied as a scrim across the image. The gradient must have a transparent component for the image to show. An overlayGradient
is equivalent to a filter that overlays the image with a named gradient. The overlayGradient
filter is applied after any filters defined by the filter
property and after the overlayColor
property.
The gradient applies only to the drawn area of the image, not the padding or any blank space left over after image scaling and alignment.
scale
Scales the image within the container.
Name | Description |
---|---|
|
Doesn't scale the image. The |
|
Scales the image non-uniformly so that the width matches the bounding box width and the height matches the bounding box height. |
|
Scales the image uniformly up or down so that the bounding box is completely covered. The |
|
Scales the image uniformly up or down so that the entire image fits within the bounding box. The |
|
Scales the image uniformly as per |
source, sources
The URL of the image to download and display.
Use https
instead of http
for image source URLs. Many Alexa devices don't support the http
scheme in skill APL documents for security reasons.
You can set this property to an array of URLs instead of a single string. When the filters
property is empty, the component displays the last image in the array. When the filters
property contains one or more filters, the filter determines which image or images to use in the array. For details about filters, see Filters
Manage alignment, scaling, and sizing of images
Image alignment and scaling can be complex. Images must have a specified height and width. The actual image must then be clipped, scaled, and positioned within the bounding box of the Image component.
The scale
mode controls how the image size is adjusted to fit the bounding box.
The align
mode controls how the image (after scaling) is positioned in the box.
Any clipping is always applied to the bounding box, not to the scaled image.
Sample image
{
"type": "Image",
"source": "https://images.example.com/image/foo.png",
"scale": "fill",
"width": 300,
"height": 300
}
In this case, the image fills a 300x300 box on the screen.
Last updated: Nov 28, 2023