java - Setting key for picasso for S3 Amazon -

-

i trying use amazon s3 client files uploading , downloading. caching trying use picasso right now.

there few points note. 1- in s3, there no single link file. have randomly generate url each image. url expire in 1 min or can set expire in 1 hour.

in oncreateview of adapter calling this

string url = getamazontempurl()

2- each file name same can modified on server. e.g abc.png file name , can 1mb today , tomorrow there 1 more image there.

now want ask how can picasso handle key such scenario. url changing time in single scroll. name same. not want picasso check name , don't download new updated file.

what want keep cache of generated urls in hashmap, , if there no value key, generate url getamazontempurl() , store in cache.

if set url expiry time hour can record activity load time variable, , check if has been longer hour. if so, clear cache.

what can do callback picasso in case image fails , recreate url:

picasso.with(this).load(imageurl).into(imgaeview, new callback() {                 @override                 public void onsuccess() {                  }                  @override                 public void onerror() {                     //recreate url here , store in cache                 }             }     );

edit:

so in case persist above cache , load next time app started. deal image changing under same url can try dirty way or clean way.

the clean way change url image if can. if that's not option - can perhaps check image's last modified date , append timestamp on url. e.g http://www.sample.com/image.jpg?14869246263 - works fine picasso's cache long the url same.

the dirty way load cached version , after force-reload same image around cache (used done skipcache() believe, deprecated in favour of somethingcachepolicy).


Comments

Post a Comment

Popular posts from this blog

how to do line continuation in perl debugger for entering raw multi-line text (EOT)? -

-
i learning perl. trying in debugger define variable, here-document. not know how enter same code in perl script, in debugger. due new lines present inside eot, makes hard in interactive debugger. here small example. have script: >cat ex1.perl #!/usr/bin/perl -w $s =<<'eot'; first line second line eot print $s now run , gives expected output: >perl ex1.perl first line second line now want same in debugger. tried this: >perl -de0 loading db routines perl5db.pl version 1.39_10 db<1> $s =<<'eot';\ cont: first line\ cont: second line\ cont: eot can't find string terminator "eot" anywhere before eof @ (eval 6) [/usr/share/perl/5.18/perl5db.pl:732] line 2. @ (eval 6)[/usr/share/perl/5.18/perl5db.pl:732] line 2. eval 'no strict; ($@, $!, $^e, $,, $/, $\\, $^w) = @db::saved;package main; $^d = $^d | $db::db_stop; $s =<<\'eot\'; first line second line eot; ' called @ /usr/share/perl...
Read more

android - Linear layout children not scrolling -

-
i'm trying add image views linear layout @ runtime. <linearlayout android:id="@+id/llfolderlayout" android:layout_width="match_parent" android:layout_height="0dp" android:layout_weight=".65" android:orientation="horizontal" android:scrollbars="horizontal" > </linearlayout> linearlayout llfoldertabs = (linearlayout) myfolder.findviewbyid(r.id.llfolderlayout); imageview imgtab = new imageview(activity); imgtab.setid(i); imgtab.settag(i); imgtab.setimagedrawable( mcontext.getresources().getdrawable(r.drawable.icon_folder_inactive)); if (i == 0) { imgtab.setimagedrawable( mcontext.getresources().getdrawable(r.drawable.icon_folder_active)); // imgtab.setpadding(10, 0, 4, 0); linearlayout.layoutparams lp = new linearlayout.layoutparams( 74, layoutparams.match_parent); lp.setmargins(15, 0, 0, 0); imgtab.setlayoutparams(lp); } else { // imgtab....
Read more

javascript - Create websocket without connecting -

-
is there way create websocket without connecting right away? far think var ws = new websocket("ws://ws.my.url.com"); creates , connects right away. i'd create socket, define callbacks, , connect once user clicks connect button. thanks no. creating websocket means you've created connection server (or started process of connecting). there no such thing creating websocket isn't connecting yet. you create object store configuration parameters , tell object connect when wanted to, though i'm not sure why that's better creating actual websocket when connect made. or create function setup work , call function later when user clicks connect button.
Read more