Fix: Use buffered backend to prevent flickering

This is reported to be occuring with the Cursive Termion backend as it redraws
the screen every time, resulting in flickering for some users.

Should be removed once Cursive has integrated this.

See also:
- https://github.com/gyscos/cursive/issues/142
- https://github.com/gyscos/cursive/issues/667

Fixes #934

Cargo.lock

@@ -537,6 +537,20 @@ dependencies = [
  "unicode-width",
 ]
 
+[[package]]
+name = "cursive_buffered_backend"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e902dfdc09ca6729606f45a5ce6ce4ef9637fc257e8b11ca7806fc9aabd03cf7"
+dependencies = [
+ "cursive_core",
+ "enumset",
+ "log",
+ "smallvec",
+ "unicode-segmentation",
+ "unicode-width",
+]
+
 [[package]]
 name = "cursive_core"
 version = "0.3.5"
@@ -1575,6 +1589,7 @@ dependencies = [
  "clipboard",
  "crossbeam-channel",
  "cursive",
+ "cursive_buffered_backend",
  "dbus",
  "dbus-tree",
  "fern",

Cargo.toml

@@ -45,6 +45,7 @@ tokio-stream = "0.1.9"
 toml = "0.5"
 unicode-width = "0.1.9"
 url = "2.2"
+cursive_buffered_backend = "0.6.1"
 [target.'cfg(target_os = "linux")'.dependencies]
 wl-clipboard-rs = {version = "0.6", optional = true}
 

src/main.rs

@@ -166,7 +166,10 @@ async fn main() -> Result<(), String> {
         credentials = credentials_prompt(Some(error_msg))?;
     }
 
-    let mut cursive = cursive::default().into_runner();
+    let backend = cursive::backends::try_default().map_err(|e| e.to_string())?;
+    let buffered_backend = Box::new(cursive_buffered_backend::BufferedBackend::new(backend));
+
+    let mut cursive = cursive::CursiveRunner::new(cursive::Cursive::new(), buffered_backend);
     cursive.set_window_title("ncspot");
 
     let theme = cfg.build_theme();