There is very simple and usefull and free plugin.
The Bitnami Redmine plugins are in installdir/apps/redmine/htdocs/plugins
Before install you should execute installdir/use_redmine
Then change cur dir to installdir/apps/redmine/htdocs and start migration
bundle exec rake redmine:plugins NAME=redmine_checklists RAILS_ENV=production
My site uses Twenty Fourteen theme. But the theme is very narrow.
Actually, the loading images from URL to ImageView (ImageView itself is in GridView or ListView) is not a simple task. You should provide memory and disk caching to avoid reload image again and again.
The simpliest way to show progress in ActionBar is
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
setContentView(R.layout.activity_main);