Implementing Public Preview
This topic describes how to implement a public preview for the Smart Hub Preview feature. A public preview shows the same preview content to all users.
Related Info
Samples
Public preview content is defined by a remotely-hosted JSON file. You can configure the JSON file to expire and refresh at a specific time. The public preview generation process is shown in the following figure.
- The URL of the remote JSON file is defined in the application's "config.xml" file.
- The preview is generated and shown based on the JSON data.
- The user clicks a preview tile.
- The JSON
action_data
value corresponding to the selected tile is sent to the application. - The application parses the
action_data
value and shows the detail page.
Prerequisites
To enable your application to use the public preview functionality:
-
Define the remote JSON file URL in the "config.xml" file:
<tizen:metadata key='http://samsung.com/tv/metadata/use.preview' value='endpoint_URL=http://yourServer/JSONfile.json'></tizen:metadata>
-
Disable reloading the application main page when it receives an application control request. This allows your application, if it is already running, to receive the
action_data
information without reloading.<tizen:app-control> <tizen:src name='index.html' reload='disable'></tizen:src> <tizen:operation name='http://samsung.com/appcontrol/operation/eden_resume'></tizen:operation> </tizen:app-control>
-
If you want the application to support 2015 TV models, set the
required_version
attribute to "2.3" and the development API version meta data attribute to "2.4" in the "config.xml" file:<tizen:application ... required_version='2.3'></tizen:application> <tizen:metadata key='http://samsung.com/tv/metadata/devel.api.version' value='2.4'></tizen:metadata>
Configuring Public Preview Data
The preview content is defined in JSON format. The application can only use 1 preview content JSON file at a time.
The following table lists the structure and parameters for the preview content JSON data.
Parameter | Type | Mandatory | Description | ||
---|---|---|---|---|---|
expires
|
UNIX timestamp | false | For public preview only If specified, the time at which the preview content is updated. The time is at most 1 week into the future. By default, the preview content is updated every 10 minutes, whenever the TV is switched on, or the JSON file changes. |
||
expires_only
|
Boolean | For public preview only If this value is "true", the preview content is updated only at the time specified by the expires parameter. The default value is "false". It is supported in 2018 TV models and newer.
|
|||
sections
|
Array | true | Preview sections | ||
title
|
String | false | Section title | ||
position
|
Integer | Section position If specified, sections are shown in ascending position order. |
|||
title_display_mode
|
String | The following three values are supported:
|
|||
subtitle_display_mode |
String | The following three values are supported:
|
|||
tiles
|
Array | true | Tiles within the section | ||
title
|
String | false | Tile title | ||
subtitle
|
Tile subtitle | ||||
image_url
|
true | Thumbnail image URL | |||
image_ratio
|
Thumbnail image aspect ratio:
|
||||
action_data
|
Data to send to the application when the tile is clicked | ||||
is_playable
|
If "true", a "Play" icon is shown over the thumbnail image | ||||
display_from |
UNIX timestamp | false | Time to begin showing the tile | ||
display_until
|
Time to stop showing the tile | ||||
position
|
Integer | Section position If specified, sections are shown in an ascending order by the position value. |
Table 1. Preview JSON parameters
For an example of a preview content JSON file, see sampleJSON.
The JSON parameters title_display_mode
and subtitle_display_mode
for displaying title and subtitle of tiles, respectively, support the following options:
AlwaysOn
- If this option is enabled, the title or subtitle is always displayed when the preview is visible.
HighlightedOnly
- This is the default option, which shows the title or subtitle when the tile is in focus.
AccessibilityOnly
- If this option is enabled, the title or subtitle is not displayed. There is only a Voice Guide when the accessibility setting is set to ON and the preview tile is in focus.
Please note that this behavior is an accessibility feature to assist users, and it should comply with the policies of the countries the application is released in.
If only the preview tile image is to be shown to user, and the title and subtitle are required to be hidden, add the title and subtitle values to the JSON file, and set the
AccessibilityOnly
value for both properties. This ensures that the title and subtitle will not be visible to user, but are read out loud when the tile is in focus.When the preview system requests JSON data from your server, TV information is sent in the HTTP header. You can serve different preview content depending on TV information, such as the language, and application version.
The following table lists the HTTP header fields that contain TV information.
Field | Description |
---|---|
ACCEPT-LANGUAGE
|
TV language setting, such as 'en-US' |
X-SAMSUNG-APP-VERSION
|
Application version |
X-SAMSUNG-COUNTRY-CODE
|
TV Smarthub country setting, such as 'US' in ISO 3166-1 Alpha 2 Format |
Table 2. HTTP header fields
Implementing Public Preview Deep Links
When a tile is clicked, its associated action_data
value is converted to an ApplicationControlData
object with the PAYLOAD
key:
{
"key": "PAYLOAD",
"value": ["{\"values\": \"{\\\"videoIdx\\\": 1}\"}"]
}
For more information on ApplicationControlData
objects, see the Application API.
To implement deep-linking:
-
To receive
action_data
information when the application is already running, add an event listener for theappcontrol
event to theonload
property:window.addEventListener('appcontrol', deepLink);
-
In the
onload
property, receive and parse thePAYLOAD
key value, using thegetCurrentApplication().getRequestedAppControl()
method:function deepLink() { var requestedAppControl = tizen.application.getCurrentApplication().getRequestedAppControl(); var appControlData; var actionData; var videoIdx; var pictureIdx; if (requestedAppControl) { appControlData = requestedAppControl.appControl.data; for (var i = 0; i < appControlData.length; i++) { if (appControlData[i].key == 'PAYLOAD') { actionData = JSON.parse(appControlData[i].value[0]).values; if (JSON.parse(actionData).videoIdx) { videoIdx = JSON.parse(actionData).videoIdx; console.log(videoIdx); } else if (JSON.parse(actionData).pictureIdx) { pictureIdx = JSON.parse(actionData).pictureIdx; console.log(pictureIdx); } } } } else { console.log("no req app control"); } }