Develop Reference

Profile Image Uploader and Load it with Picasso

I have an android app which has profile image.
The user can edit his/her profile image.
I'm using Picasso to load images, but every time I load profile image, Picasso loads old image.
When I upload profile image I don't change it's url, so profile image url for every user is constant.
First question: should I change profile image url every time user change profile image?
Second question: When user change his/her profile image I invalidate Picasso to load new image using this code:
picassoInstance.load(url)
.networkPolicy(NetworkPolicy.NO_CACHE)
.transform(new CircleTransform())
.placeholder(dr)
.into(imageView);
But Picasso show me the old one.
And one more thing:
I load image url into imageView without calling networkPolicy method at first.
How should I handle this problem?

Every Image has different name, whenever new image uploaded you have to update your image Url
Eg. current url : https://photographylife.com/nikon-d810-high-resolution-image-samples
where Image name is : nikon-d810-high-resolution-image-samples
and after uploaded new image, name will be different for example : image-sample
so you need to update that image Url : https://photographylife.com/image-sample with new name
try this, i telling you cause im doing the same hope this will help you!

So lets just discuss one by one:
Should I change profile image url every time user change profile
image?
No. You might think of other ways around. In my case, I download the picture each time the url changes with a specific name of the user (as we're considering profile picture). So when I loaded the image with Picasso I passed the file path instead of the URL so that, it won't fetch from the URL each time. Picasso doesn't do that either actually. It maintains a cache. If the file doesn't exist, just put a placeholder.
When user change his/her profile image I invalidate Picasso to load
new image using this code:
I don't see any invalidate code here in your code. I would refer to this link to see how they've solved the cache problem.
I load image url into imageView without calling networkPolicy method
at first.
So if you fetch the image from the external storage, I don't think there's a necessity to do so.
And another suggestion is to use Glide in these cases. This is almost the same thing as Picasso, but personally I like to use Glide instead of Picasso.
Hope that helps.

Using Glide instead of Picasso because Glide recommended by google
http://inthecheesefactory.com/blog/get-to-know-glide-recommended-by-google/en
Preventing for caching in Glide
Glide.with(DemoActivity.this)
.load(Uri.parse("file://" + imagePath))
.diskCacheStrategy(DiskCacheStrategy.NONE)
.skipMemoryCache(true)
.into(mImage);

Add this class to the com.squareup.picasso package.
package com.squareup.picasso;
public class PicassoTools {
public static void clearCache (Picasso p) {
p.cache.clear();
}
}
Because cache has package visibility, this util class can clear the cache for you. You just have to call it:
PicassoTools.clearCache(Picasso.with(context));

I find where problem is:
I turned down disk cache but not memory cache. I should use this code:
picassoInstance.load(url)
.networkPolicy(NetworkPolicy.NO_CACHE)
.memoryPolicy(MemoryPolicy.NO_CACHE)
.transform(new CircleTransform())
.placeholder(dr)
.into(imageView);
I use this link to:
picasso-influencing-image-caching
Thanks everybody

You need to invalidate the file before loading use the code given below:
Picasso.with(getActivity()).invalidate(file);
To know more details kindly study the Picasso documentation from their website.

Android - use picasso to load image without storing it in cache

I want to use picasso to load an image from a url into a placeholder, but not store that image in cache - in other words, I want the image to be downloaded from the net directly to disk and then loaded from disk when needed. I understand there's a class called RequestCreator where you can specify memory policy - does anyone have an example of using picasso/requestcreator to do something like this?
So.. something like:
RequestCreator requestCreator = new RequestCreator();
requestCreator.memoryPolicy(MemoryPolicy.NO_CACHE);
....
merged with:
Picasso.with(context).load(someurl).fit().placeholder(someplaceholder).into(sometarget)..

Picasso supports this by it's skipMemoryCache() in the Picasso builder. An example is shown below.
Picasso.with(context).load(imageUrl)
.error(R.drawable.error)
.placeholder(R.drawable.placeholder)
.skipMemoryCache()
.into(imageView);
With the new API you should use it like this so that it skips looking for it and storing it in the cache:
Picasso.with(context).load(imageUrl)
.error(R.drawable.error)
.placeholder(R.drawable.placeholder)
.memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE)
.into(imageView);
NO_CACHE
Skips memory cache lookup when processing a request.
NO_STORE
Skips storing the final result into memory cache. Useful for one-off requests to avoid evicting other bitmaps from the cache.

For picasso:2.71828 or above version use the following for skipping using disk cache networkPolicy(NetworkPolicy.NO_CACHE) :
Picasso.get()
.load(camera_url)
.placeholder(R.drawable.loader2)
.networkPolicy(NetworkPolicy.NO_CACHE, NetworkPolicy.NO_STORE)
.into(img_cam_view);

Picasso 2.5.0
If you are using Picasso to load image from Internet, you have to use NetworkPolicy attribute.
.networkPolicy(NetworkPolicy.NO_STORE)
but live memory cache (Not disk cache) is useful, you might want to keep it.

just append this at the end of url.
"?=" + System.currentTimeMillis();

Android Ion Cache Refresh

I'm using a specific url to obtain an image online, but the url itself automatically changes every few minutes.
I'm using ION library from Here
The problem I'm having is when I refresh the page, the page itself looks like it is refreshing but the exact same picture is appearing.
I'm assuming its a cached image? If I reinstall the application, then it obtains the correct image again.
This is how I'm using ION where imageID2[position] is just a typical url to a jpg.
Ion.with(imageView)
.placeholder(R.drawable.ic_launcher)
.error(R.drawable.ic_launcher)
.load(imageId2[position]);
Is there anyway I can disable the cache or just make it refind the images again?

Use .noCache() to bypass caches.

As per documentation here, use the "long" way to build an ImageView request so that you can add headers, noCache, etc.
Change your original request from this:
Ion.with(imageView)
.placeholder(R.drawable.ic_launcher)
.error(R.drawable.ic_launcher)
.load(urlString);
To this:
Ion.with(context)
.load(urlString)
.noCache()
.withBitmap()
.placeholder(R.drawable.ic_launcher)
.error(R.drawable.ic_launcher)
.intoImageView(imageView);

You can append a unique string to your url for example a current timestamp in order to force Ion to treat each request as unique.

How to inform Picasso that the image in the link changed?

im using picasso library to load images.
However in my application, users can have profile pictures and the link for the image is constant... Picasso has no clue that the image has changed...
I tried using : .skipMemoryCache() but it wasn't an ideal solution...
Is there a way to check if there's a new picture in the same link using picasso? Thanks!

Apparently, there is no API in the current (2.3.2) version of Picasso to achieve this (but it is a work in progress - see this bug).
That aside, if you have control of the server side, you may want to think about your design decision to provide the changing profile picture at a constant URL.
An alternative would be: Include the current profile picture URL in the profile information you retrieve. This way, your cache can use the cached image - and as soon as the profile information provides a new URL, Picasso will fetch it. In all other cases, Picasso can leverage the cache.

I got the answer from this link
change your URL as shown below:
String imageurl = url + "?time=" + System.currentTimeMillis();
Picasso.with(getContext()).load(imageurl).into(imageView);
this worked for me. thanks

Picasso.with(context)
.load(url)
.memoryPolicy(MemoryPolicy.NO_CACHE)
.networkPolicy(NetworkPolicy.NO_CACHE)
.fit()
.placeholder(YOUR PLACE HOLDER RESOURCE)
.centerCrop()
.into(imageView);

One solution is to invalidate the cache like so
Picasso.with(context).invalidate(imagePath);
The other way to force download the image which then is cached for subsequent use as mentioned in the code.
Picasso.with(context)
.load(imagePath)
.networkPolicy(NetworkPolicy.NO_CACHE)
.into(userAvatar);

(Glide) Getting image from cache if it exists

I have trouble when I'm using Glide in my app. As I've understood, if image was downloaded once and I request image from cache from other activity, Glide must show image quick. And I got this behavior, but not in my app. Image loads very slow (about 3 seconds), although in another app it was about 0.4 second.
My code with calling Glide:
Glide.with(this)
.load(url)
.signature(new StringSignature(url))
.diskCacheStrategy(DiskCacheStrategy.ALL)
.into(mHeader);
And in other activity code are same.
May you help me?
Thanks

You don't need the signature(url) part, the model (url String in your case) is already a part of the cache key.
The problem may be that your header changes size. The view size (= resulting Bitmap size) needs to be constant for a cache hit. However since you're doing ALL caching the load should still be fast. Is there anything changing in the url maybe, like a sessionid or similar? That would make the cache miss.
If the url you're loading is an animated GIF RESULT caching can be the culprit, here's a reference.