android在设备上加载和保存图像

Question

I am building the application that will load list of news from the website. Each news/headline has an image. I want to save/cash the images so user does not has to download them again.

Q: In your opinion, what would be a better/more sufficient way: Loading images and saving them on the device or use the CacheManager? At the moment I am using the first solution and everything works fine. However, the website has many categories and even more news per category therefore there are lot of images saved on the device. Is it normal in this type of applications to save the images on the device?

Thanks for your help, marqs

Answer 1

I didn't find a reason to use CacheManager. I used getCacheDir and stored everything on file. I have two levels of cache. First when I fetch it, I store in memory and disk. When in memory gets bigger than 30 objects, I started clearing the memory to make some room for the new images coming. However, I still keep the images around on disk and bring in to memory as needed. I found this to give me the smoothest scrolling. After about an hour, I start expiring the image on disk too.

Answer 2

I don't think you should save the images on the device, because of many reasons:

1. Why wasting the device space on news images? All the user wants is to read the news and thats it. (In your case maybe open it later, but still - not forever)
2. You can save it on the device and make the app. delete those files after lets say 24 hours..
3. The main issue is the privacy issue, when the user is deleting the cache files he thinks all the webs he visited has wiped from the device, but in this case they aren't..

Maybe you can just add a "Clean Cache" button in the app. but after all I wrote I think using the Cache-manager is the best way - just because it was meant for those things exactly..

:)

Rotem