The following questions are related to implementing the Smart Hub Preview feature.
Smart Hub Preview is a feature for Samsung Smart TVs that allows you to show content when the user hovers over your application icon in the launcher. The user can click the preview tile to open the content directly within the application. You can use the preview to promote new or personalized content to the user. For more information, see Smart Hub Preview.
#preview #launcher #personalized content
Make sure your JSON file URL and the defined tile image URLs are valid. Invalid tile image URLs can cause unexpected Smart Hub Preview behavior.
#tile image #preview tile
Smart Hub Preview is supported since 2016 TV models. It is also supported on the TV emulator since Tizen TV Extension 2.3.1.
#tv model #emulator #feature support
When implementing a personal preview, the background service application is required. While the foreground application performs the main application tasks, such as showing content, the background service application serves information to show in the preview. For more information on implementing a personal preview, including the background service application, see Implementing Personal Preview.
#personal preview #background service application
Smart Hub Preview tile images must be at least 250 px tall, with an aspect ratio of 16:9, 4:3, 1:1, or 2:3. Larger images are reduced to fit the specified aspect ratio. For more information, see Tile Element Specifications.
#tile #size #image #aspect ratio
Since languages can have different display character widths, there is no defined text length limit. However, long titles or subtitles can cause unintended Smart Hub Preview behavior.
#section title #tile title #tile subtitle #title length
The title and subtitle are only shown when the tile has focus. If you want to show text on the tile image even when it does not have focus, you can implement the text in the tile image itself.
#tile title #tile subtitle
You can define the JSON file as either "text/plain" or "application/json" type.
#json file #media type #mime type #content type
By default, the preview content is updated every 10 minutes and whenever the TV is switched on.
You can also define a specific update time with the expires property, and define a new update time in the updated feed. The minimum time between updates is 10 minutes. After the feed updates at the defined time, if no new expires property is specified, the preview content is updated every 10 minutes.
expires
#feed update #update interval #refresh interval
To show different content on Smart Hub Preview for specific model groups, such as 4K UHD video content on UHD TVs, you can implement a public preview. Create a separate application version that shows preview content from a different JSON file URL, and submit it for the applicable model groups.
Alternatively, you can implement a personal preview, which allows you to customize the preview content for the user. Use the ProductInfo API to retrieve the model information from the TV, and use the background service application to serve content based on the model information retrieved.
#public preview #private preview #model group #4k #uhd #productinfo api
If the application is installed from a USB removable drive on a 2017 or later TV model, Smart Hub Preview does not work. This is a known limitation.
#install #usb #missing tile #testing
The preview content is updated in the following scenarios:
To implement preview content updates:
use.preview
config.xml
ON-START()
onRequest()
getCurrentApplication().exit()
#background service application #application api #private preview #public preview
Before launching the background service application, make sure the TV supports it:
tizen.systeminfo.getCapability("http://tizen.org/feature/web.service");
When you use the launchControl() method to launch a background service application on a TV that does not support service applications, it causes unexpected behavior in the foreground application, such as missing images and corrupted video playback.
launchControl()
#background service application #launchcontrol #missing image #feature support