I read something about this issues but I didnt understand as well:
1: if I .resize(x,y) an image in my code, then Picasso caches only the original size or the resized one too?
2: memory and disk cache are storing with different cache-key?
Yes and no.
Picasso caches resized images. If you call resize(50, 50) on a URL twice the second request will use the resized image which was cached in memory. The HTTP client will never see the URL a second time in this case.
The HTTP client that Picasso uses will cache the original image (if configured to do so and the headers allow it). If you call resize(50, 50) on a URL the original will be cached on disk by the HTTP client so that if you call resize(100, 100) on that URL the HTTP client does not need to fetch the image again.
The HTTP client cache is completely opaque to Picasso. It doesn't see or control its contents. Picasso makes an HTTP request for every URL that isn't available in the memory cache and whether the HTTP client downloads it or serves it from the local cache is completely controlled inside the HTTP client.
1 - Yes, picasso only caches the original size.
2 - Yes.
The global default Picasso instance returned from with() is automatically initialized with defaults that are suitable to most implementations.
LRU memory cache of 15% the available application RAM
Disk cache of 2% storage space up to 50MB but no less than 5MB.
More information about caching in Picasso.
How do I use disk caching in Picasso?
Comparission with glide (also have infomation about caching)
http://inthecheesefactory.com/blog/get-to-know-glide-recommended-by-google/en
Related
I implemented a routine which saves data from a json into database and after that if user gets offline, he can see all data. but picasso doesn't load the images after the first run. but when i run the application twice in online mode, after that picasso can load the images from cache in offline mode.
(it should cache images on the first run but it's not working)
appreciate any suggestion
https://stackoverflow.com/a/23281195/3664628
Picasso doesn't have a disk cache. It delegates to whatever HTTP client you are using for that functionality (relying on HTTP cache semantics for cache control). Because of this, the behavior you seek comes for free...
The main reason may be other images are evicting the older ones from the cache due to their size. You can load smaller versions or increase the size of the memory cache like this
Picasso p = new Picasso.Builder(context)
.memoryCache(new LruCache(Size))
.build();
If you don't want to save in cache, You can Additionally exclude that too using Memory Policy.
Picasso attempts to get the requested image from the memory first. If you would like Picasso to skip this step, you can call memoryPolicy(MemoryPolicy policy, MemoryPolicy... additional) on your Picasso request creator. MemoryPolicy is a simple enum with two values: NO_CACHE and NO_STORE. like this
Picasso
.with(context)
.load(UsageExampleListViewAdapter.eatFoodyImages[1])
.memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE)
.into(imageViewFromDisk);
Additional Source : futurestud.io
I'm trying to a load bigger size image (in some hundreds of KB's) using Picasso in Android. But it seems the image is loaded every time from internet and fails to load (or retrieve) from disk cache (if unavailable in main memory).
I think it may be due to the following problem.
The image size is huge (100KB-300KB).
The Cache-Control property is not defined in HTTP Response Header.
So my question is
Is there any limitation for image size in disk caching? What if the image size is huge and How does Picasso caching mechanism works in such cases?
Is it mandatory to set Cache-Control property in Response Header? How does Picasso consider this for caching mechanism?
If anything else is behind this mechanism as a reason, please explain.
I have activity in which there is a dialog window with some images. I want to download these images into cache when my activity starts and load them from cache when dialog window appears.
My activity code:
for(int i=0; i<avataritemlist.size();i++){
Picasso.with(activity_context)
.load(item.getpath())
.noFade();
}
Dialog adapter code:
Picasso.with(mContext)
.load(item.getpath())
.noFade()
.into(holder.imageView);
I expect to cache the image in my activty and then in dialog adapter load in from cache, but in my case it downloads it again in adapter. I want to emphasize that activity_context and mContext is the same. What am I doing wrong?
Default Picasso instance returned by Picasso.with uses an automatic memory and disk caching. It is initialized with default values:
• LRU memory cache of 15% the available application RAM
• Disk cache of 2% storage space up to 50MB but no less than 5MB. (Note: this is only available on API 14+ or if you are using a standalone library that provides a disk cache on all API levels like OkHttp)
• Three download threads for disk and network access.
How default Picasso instance does LRU memory cache is something you might not be able to know, all you know is it is a memory cache which uses a least-recently used eviction policy.
However you can create a Picasso instance using Picasso.Builder that gives you a better control over image caching (over disk). Check more on this stackoverflow post on how to set up http request header property Cache-Control with max-age and Jake Wharton's answer too
Also you may also want to try out Glide which syntactically is very similar to Picasso
Before I had worked on Volley and I have used the DiskLruCache [link] with Volley to cache images on disk.
Now I have been working with app that is using Picasso.
I would like to know whether Picasso supports disk caching.
If it supports how can I fix the cache size.
Which will be useful when loading images from remote with disk caching?
Picasso supports disk caching, and it's relying on the HTTP client for this.
If you're using it with OkHttp, the default size for the disk cache will be around 50 MB (2% of total space, max 50MB, min 5MB).
If this doesn't meet your needs, you can either implement your own disk cache or manually initialise the OkHttpDownloader with a larger disk cache size when you initialise your Picasso using the Picasso.Builder.
I would recommend the latter, it should look something like
new Picasso.Builder(context).downloader(new OkHttpDownloader(MAX_CACHE_SIZE)).build();
I am using Picasso to load images in a container. I want to cache in memory and cache in disk.
What is the best way to cache a image in disk? What http client is the best option?
These are my requirements:
First check cache in memory
Check cache in disk
Get the image from the server.
If the image is on disk -> check cache interval(max-age) and validate with server if the image is stale. The server needs in the header if_none_match: eTag.
I've read that this feature is built in the OkHttp api, but I don't know how to use it. Please I would appreciate somebody to send me some link, documentation or if any other different way of doing this that you could consider.