Fix test

lvgl/src/input_device.rs

@@ -123,7 +123,7 @@ where
 #[cfg(test)]
 mod test {
     use super::*;
-    use crate::{Color, UI};
+    use crate::UI;
     use core::marker::PhantomData;
     use embedded_graphics::drawable::Pixel;
     use embedded_graphics::geometry::Size;
@@ -133,14 +133,14 @@ mod test {
 
     struct FakeDisplay<C>
     where
-        C: PixelColor + From<Color>,
+        C: PixelColor,
     {
         p: PhantomData<C>,
     }
 
     impl<C> DrawTarget<C> for FakeDisplay<C>
     where
-        C: PixelColor + From<Color>,
+        C: PixelColor,
     {
         type Error = ();
 
@@ -161,14 +161,13 @@ mod test {
 
         let disp: FakeDisplay<Rgb565> = FakeDisplay { p: PhantomData };
 
-        ui.disp_drv_register(disp);
+        ui.disp_drv_register(disp)?;
 
-        fn read_touchpad_device() -> Point {
-            Point::new(120, 23)
+        fn read_touchpad_device() -> BufferStatus {
+            InputData::Touch(Point::new(120, 23)).pressed().once()
         }
 
-        let mut touch_screen =
-            Pointer::new(|| InputData::Touch(read_touchpad_device()).pressed().once());
+        let mut touch_screen = Pointer::new(|| read_touchpad_device());
 
         ui.indev_drv_register(&mut touch_screen)?;
 

lvgl/src/ui.rs

@@ -58,6 +58,18 @@ where
     }
 
     pub fn indev_drv_register(&mut self, input_device: &mut Pointer) -> LvResult<()> {
+        if self.display_data.is_none() {
+            // TODO: Better yet would be to create a display struct that one register the
+            // input device in that instance. Represents better the LVGL correct usage. Also it's
+            // inline with unrepresentable invalid states using Rust type system.
+            // ```rust
+            // let disp = ui.disp_drv_register(embed_graph_disp)?;
+            // disp.indev_drv_register(disp);
+            // ...
+            // window.update(&disp)
+            // ```
+            return Err(LvError::Uninitialized);
+        }
         unsafe {
             let descr = lvgl_sys::lv_indev_drv_register(&mut input_device.driver as *mut _);
             input_device.set_descriptor(descr)?;