Added fix to error on close.

Cargo.lock

@@ -497,6 +497,7 @@ dependencies = [
  "bytemuck",
  "kayak_core",
  "kayak_font",
+ "log",
  "serde",
  "serde_json",
  "serde_path_to_error",

bevy_kayak_ui/Cargo.toml

@@ -11,6 +11,7 @@ bevy_kayak_renderer = { path = "../bevy_kayak_renderer" }
 serde = "1.0"
 serde_json = "1.0"
 serde_path_to_error = "0.1"
+log = "0.4"
 
 [dependencies.bevy]
 version = "0.8.0"

bevy_kayak_ui/src/lib.rs

@@ -63,10 +63,12 @@ pub fn process_events(world: &mut World) {
         if let Some(window) = windows.get_primary() {
             Vec2::new(window.width(), window.height())
         } else {
-            panic!("Couldn't find primary window!");
+            log::warn!("Couldn't find primiary window!");
+            return;
         }
     } else {
-        panic!("Couldn't find primary window!");
+        log::warn!("Couldn't find primiary window!");
+        return;
     };
 
     if let Some(bevy_context) = world.remove_resource::<BevyContext>() {

examples/nine_patch.rs

 use bevy::{
     prelude::{App as BevyApp, AssetServer, Commands, Handle, Res, ResMut},
+    render::texture::ImageSettings,
     window::WindowDescriptor,
     DefaultPlugins,
 };
@@ -72,6 +73,7 @@ fn main() {
             title: String::from("UI Example"),
             ..Default::default()
         })
+        .insert_resource(ImageSettings::default_nearest())
         .add_plugins(DefaultPlugins)
         .add_plugin(BevyKayakUIPlugin)
         .add_startup_system(startup)