how to show text

src/debug_view.rs

@@ -0,0 +1,61 @@
+use bevy::prelude::*;
+
+const DEBUG_PINK: Color = Color::rgb(0.8, 0.2, 0.2);
+
+#[derive(Component)]
+struct DebugView;
+
+pub struct DebugViewPlugin;
+
+impl Plugin for DebugViewPlugin {
+    fn build(&self, app: &mut App) {
+        info!("setting up the DebugView plugin");
+        app
+            .add_startup_system(init_view)
+            .add_system(debug_input);
+    }
+}
+
+fn init_view(mut commands: Commands, asset_server: Res<AssetServer>) {
+    let mut root = commands.spawn();
+
+    root.insert(DebugView);
+    root.insert_bundle(NodeBundle{
+        visibility: Visibility{is_visible: false},
+        style: Style{
+            size: Size::new(Val::Percent(100.0), Val::Percent(100.0)),
+            ..default()
+        },
+        color: Color::NONE.into(),
+        ..default()
+    });
+
+    root.with_children(|parent| {
+        let textStyle = TextStyle{
+            font: asset_server.load("fonts/FiraSans-Bold.ttf"),
+            font_size: 20.0,
+            color: DEBUG_PINK,
+        };
+        let textBundle = TextBundle::from_section("fart", textStyle)
+            .with_text_alignment(TextAlignment::TOP_RIGHT)
+            .with_style(Style{
+                align_self: AlignSelf::FlexEnd,
+                position_type: PositionType::Absolute,
+                position: UiRect {
+                    top: Val::Px(5.0),
+                    right: Val::Px(5.0),
+                    ..default()
+                },
+                ..default()
+            });
+        parent.spawn_bundle(textBundle);
+    });
+}
+
+fn debug_input(now: Res<Input<KeyCode>>, mut query: Query<&mut Visibility, With<DebugView>>) {
+    let mut visibility = query.single_mut();
+
+    if now.just_pressed(KeyCode::F10) {
+        visibility.is_visible = !visibility.is_visible;
+    }
+}

src/main.rs

@@ -1,11 +1,13 @@
 mod input;
+mod debug_view;
 
 use bevy::{
     input::{keyboard::KeyCode, Input},
     prelude::*,
 };
 
-use input::{PlayerInput, ButtonState};
+use input::PlayerInput;
+use debug_view::DebugViewPlugin;
 
 #[derive(Component)]
 struct Player;
@@ -60,9 +62,6 @@ fn player_keyboard_input(now: Res<Input<KeyCode>>, mut input_state: ResMut<Playe
     input_state.update(&now);
 }
 
-fn debug_input(now: Res<Input<KeyCode>>, mut debug_state: ResMut<DebugView>) {
-}
-
 fn player_movement(
     mut query: Query<&mut Transform, With<Player>>,
     input_state: Res<PlayerInput>,
@@ -75,17 +74,18 @@ fn player_movement(
     if input_state.right.pressed { player_t.translation.x += tile.width as f32; }
 }
 
-#[derive(Default, Debug)]
-struct DebugView {
-    enabled: bool,
-}
-
 fn main() {
     App::new()
+        .insert_resource(bevy::log::LogSettings{
+            // set to TRACE|DEBUG|INFO|WARN|ERROR to change log verbosity.
+            // INFO is the default level.
+            level: bevy::log::Level::INFO,
+            ..default()
+        })
         .add_plugins(DefaultPlugins)
+        .add_plugin(DebugViewPlugin)
         .insert_resource(ClearColor(BACKGROUND_COLOR))
         .insert_resource(PlayerInput::default())
-        .insert_resource(DebugView::default())
         .insert_resource(TileSize{width: TILE_WIDTH, height: TILE_HEIGHT})
         .add_startup_system(setup)
         .add_system(player_keyboard_input)