Refactor pagination code into separate file

src/ui/listview.rs

@@ -27,72 +27,9 @@ use crate::traits::{IntoBoxedViewExt, ListItem, ViewExt};
 use crate::ui::album::AlbumView;
 use crate::ui::artist::ArtistView;
 use crate::ui::contextmenu::ContextMenu;
+use crate::ui::pagination::Pagination;
 use crate::{album::Album, spotify::URIType, spotify_url::SpotifyURL};
 
-pub type Paginator<I> = Box<dyn Fn(Arc<RwLock<Vec<I>>>) + Send + Sync>;
-
-pub struct Pagination<I: ListItem> {
-    max_content: Arc<RwLock<Option<usize>>>,
-    callback: Arc<RwLock<Option<Paginator<I>>>>,
-    busy: Arc<RwLock<bool>>,
-}
-
-impl<I: ListItem> Default for Pagination<I> {
-    fn default() -> Self {
-        Pagination {
-            max_content: Arc::new(RwLock::new(None)),
-            callback: Arc::new(RwLock::new(None)),
-            busy: Arc::new(RwLock::new(false)),
-        }
-    }
-}
-
-// TODO: figure out why deriving Clone doesn't work
-impl<I: ListItem> Clone for Pagination<I> {
-    fn clone(&self) -> Self {
-        Pagination {
-            max_content: self.max_content.clone(),
-            callback: self.callback.clone(),
-            busy: self.busy.clone(),
-        }
-    }
-}
-
-impl<I: ListItem> Pagination<I> {
-    pub fn clear(&mut self) {
-        *self.max_content.write().unwrap() = None;
-        *self.callback.write().unwrap() = None;
-    }
-    pub fn set(&mut self, max_content: usize, callback: Paginator<I>) {
-        *self.max_content.write().unwrap() = Some(max_content);
-        *self.callback.write().unwrap() = Some(callback);
-    }
-
-    fn max_content(&self) -> Option<usize> {
-        *self.max_content.read().unwrap()
-    }
-
-    fn is_busy(&self) -> bool {
-        *self.busy.read().unwrap()
-    }
-
-    fn call(&self, content: &Arc<RwLock<Vec<I>>>) {
-        let pagination = self.clone();
-        let content = content.clone();
-        if !self.is_busy() {
-            *self.busy.write().unwrap() = true;
-            std::thread::spawn(move || {
-                let cb = pagination.callback.read().unwrap();
-                if let Some(ref cb) = *cb {
-                    debug!("calling paginator!");
-                    cb(content);
-                    *pagination.busy.write().unwrap() = false;
-                }
-            });
-        }
-    }
-}
-
 pub struct ListView<I: ListItem> {
     content: Arc<RwLock<Vec<I>>>,
     last_content_len: usize,