All your message need to tell the UI thread is that a new image is available. You don't have to pass the image as part of the message. Usually, the background thread would download the image and put it in memory (in a list or map for instance) and then simply tell the UI thread to refresh the UI. You can see such an implementation in Photostream and Panoramio at code.google.com/p/apps-for-android
On Sat, Dec 13, 2008 at 1:05 AM, DanG <[email protected]> wrote: > > Hello - > > I'm trying to figure out the best design pattern to use here. > > I have a list view, for which each row consists of some text and an > image. This content must be downloaded from the web. Currently, the > list view is using a custom adapter, and I implemented the getView() > method to dynamically download the image as it is needed (i.e. as the > row on which it should be displayed becomes visible). > > This is all happening in the main thread, and it's having an impact on > the user experience. So I'd like to move the downloading of the image > to the background thread. I know how to do this ... but my quandary is > then, how do I pass the image information back to the main UI thread. > AFAIK, the most convenient way to pass information between threads is > using Handler.sendMessage() and including a bundle with the message > containing any information. But I don't think it's possible to include > an Image as part of a bundle, because it's not serializable. > > Do I need to write the image to disk and pass a string containing the > file path? what are some other ways I could go about passing > information about a downloaded image from the non-UI background thread > to the ui thread? > > Thanks! > Dan > > > -- Romain Guy www.curious-creature.org --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~----------~----~----~----~------~----~------~--~---
