mistakes were fixed and sins were committed

src/core/ptr.rs

@@ -12,11 +12,19 @@ impl Widget for WidgetPtr {
         }
     }
 
-    fn desired_size(&mut self, ctx: &mut SizeCtx) -> Size {
+    fn desired_width(&mut self, ctx: &mut SizeCtx) -> Len {
         if let Some(id) = &self.inner {
-            ctx.size(id)
+            ctx.width(id)
         } else {
-            Size::ZERO
+            Len::ZERO
+        }
+    }
+
+    fn desired_height(&mut self, ctx: &mut SizeCtx) -> Len {
+        if let Some(id) = &self.inner {
+            ctx.height(id)
+        } else {
+            Len::ZERO
         }
     }
 }