I am developing Android app now where I need to store image Url in DB for each object and then load this image from the web (if connection is on) OR get it form cache (if not). Picasso seems to be best lib for handling images in Android, so I starter using it. But I can not get how do I use it properly for my case. Even more - Images strangely are loaded into views right after they are first time get from API but if user starts app again, we can see placeholder only (even with internet connection on). Can someone suggest a solution or at least any kind of idea of best way to do this?
My code in Adapter (is is also same in ShowActivity):
String img_url = item.getImage(); // img_url is valid image url
Picasso.with(mContext).load(img_url).placeholder(R.drawable.plchldr).fit().centerCrop().into(holder.image);
Finally got the problem - API is returning valid image url BUT actually it (image) is hosted on S3 cloud and it is expiring till the user loads application again. So, actually saving expiring image URL is useless in this situation. I am not sure what will I do here (it seems that the only way here is hard one - storing images on SD as Bitmap). But I just wanted to tell this for those who will get similar issue.