Add Harness::new_eframe and TestRenderer trait (#5539)

Co-authored-by: Andreas Reich <r_andreas2@web.de>

crates/egui_demo_app/src/apps/image_viewer.rs

@@ -54,8 +54,9 @@ impl eframe::App for ImageViewer {
     fn update(&mut self, ctx: &egui::Context, _: &mut eframe::Frame) {
         egui::TopBottomPanel::new(TopBottomSide::Top, "url bar").show(ctx, |ui| {
             ui.horizontal_centered(|ui| {
-                ui.label("URI:");
-                ui.text_edit_singleline(&mut self.uri_edit_text);
+                let label = ui.label("URI:");
+                ui.text_edit_singleline(&mut self.uri_edit_text)
+                    .labelled_by(label.id);
                 if ui.small_button("✔").clicked() {
                     ctx.forget_image(&self.current_uri);
                     self.uri_edit_text = self.uri_edit_text.trim().to_owned();

crates/egui_demo_app/src/lib.rs

@@ -6,7 +6,7 @@ mod backend_panel;
 mod frame_history;
 mod wrap_app;
 
-pub use wrap_app::WrapApp;
+pub use wrap_app::{Anchor, WrapApp};
 
 /// Time of day as seconds since midnight. Used for clock in demo app.
 pub(crate) fn seconds_since_midnight() -> f64 {

crates/egui_demo_app/src/wrap_app.rs

@@ -38,6 +38,7 @@ impl eframe::App for DemoApp {
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct FractalClockApp {
     fractal_clock: crate::apps::FractalClock,
+    pub mock_time: Option<f64>,
 }
 
 impl eframe::App for FractalClockApp {
@@ -46,7 +47,7 @@ impl eframe::App for FractalClockApp {
             .frame(egui::Frame::dark_canvas(&ctx.style()))
             .show(ctx, |ui| {
                 self.fractal_clock
-                    .ui(ui, Some(crate::seconds_since_midnight()));
+                    .ui(ui, self.mock_time.or(Some(crate::seconds_since_midnight())));
             });
     }
 }
@@ -77,7 +78,7 @@ impl eframe::App for ColorTestApp {
 
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
-enum Anchor {
+pub enum Anchor {
     Demo,
 
     EasyMarkEditor,
@@ -161,7 +162,7 @@ pub struct State {
     http: crate::apps::HttpApp,
     #[cfg(feature = "image_viewer")]
     image_viewer: crate::apps::ImageViewer,
-    clock: FractalClockApp,
+    pub clock: FractalClockApp,
     rendering_test: ColorTestApp,
 
     selected_anchor: Anchor,
@@ -170,7 +171,7 @@ pub struct State {
 
 /// Wraps many demo/test apps into one.
 pub struct WrapApp {
-    state: State,
+    pub state: State,
 
     #[cfg(any(feature = "glow", feature = "wgpu"))]
     custom3d: Option<crate::apps::Custom3d>,
@@ -203,7 +204,9 @@ impl WrapApp {
         slf
     }
 
-    fn apps_iter_mut(&mut self) -> impl Iterator<Item = (&str, Anchor, &mut dyn eframe::App)> {
+    pub fn apps_iter_mut(
+        &mut self,
+    ) -> impl Iterator<Item = (&'static str, Anchor, &mut dyn eframe::App)> {
         let mut vec = vec![
             (
                 "✨ Demos",