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TheEndless's avatar
TheEndless
Roku Guru
15 years ago

roGridScreen and SetContentListSubset example?

Any chance we could get an example of how to use the SetContentListSubset() method of the roGridScreen? I can't seem to wrap my head around how it would be used, but I suspect it would be beneficial from a performance standpoint. I think it must be something you'd call from the isListItemFocused() event, but I'm not sure how you'd do that effectively, particularly with the fast scrolling of the grid...

Thanks in advance!
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3 Replies

  • retrotom's avatar
    retrotom
    Visitor
    15 years ago
    I tried to do that also (that's what my post about the focused event returning wrong values was initially about). To be honest, it was easier to just load everything and let the grid load everything else (images, etc.) appropriately -- using whatever algorithm the developer(s) chose. The main disadvantage I noticed is that it's a little laggy to respond to the event and then try to load the data. As you said...the grid screen is fast. And trying to do it after an item is loaded makes it slow down noticeably in my experience.
  • destruk's avatar
    destruk
    Streaming Star
    15 years ago
    roGridScreen can be very fast if it doesn't need to grab much data from the internet. What I ended up doing last time is caching all the graphics, and handling the grid screen itself, and then using a poster screen to display and retrieve content lists. The fewer layers you use, or someone was saying by using multiple cavases, you can make it nearly as responsive as the default screen types, sans button sounds of course. Hopefully the gridscreen gets a few more upgrades/added flexibility in the future. I set the content manually, but I suppose it could just as easily be changed to dynamic and simply transferred before anything is displayed on the screen. Looking over the component spec, I don't think using that feature will allow you to keep up with a .125ms interval on responsiveness, but I'd also be happy to look at an example to see what it is supposed to do in a real life environment.
  • jbrave's avatar
    jbrave
    Channel Surfer
    15 years ago
    I'm playing with this now, not sure what to do after the screen finishes displaying - I used contentlistsubset to load the visible posters. However, it doesn't, as the reference seems to suggest, load the rest in the background, it only loads the ones you tell it to, and it doesn't seem any faster than setcontentlist.

    ...

    - Joel