docs: fix links, add references, rename files (#5138)

docs/widgets/canvas.rst

@@ -1,19 +1,26 @@
+.. _lv_canvas:
+
+==================
 Canvas (lv_canvas)
 ==================
 
 Overview
 ********
 
-A Canvas inherits from `Image </widgets/img>`__ where the user can draw
+A Canvas inherits from :ref:`Image <lv_image>` where the user can draw
 anything. Rectangles, texts, images, lines, arcs can be drawn here using
 lvgl's drawing engine.
 
+.. _lv_canvas_parts_and_styles:
+
 Parts and Styles
 ****************
 
 :cpp:enumerator:`LV_PART_MAIN` Uses the typical rectangle style properties and image
 style properties.
 
+.. _lv_canvas_usage:
+
 Usage
 *****
 
@@ -32,8 +39,7 @@ Or you can use
 
 The canvas supports all the color formats like
 :cpp:enumerator:`LV_COLOR_FORMAT_ARGB8888` or :cpp:enumerator:`LV_COLOR_FORMAT_I2`. See the full
-list in the `Color formats </overview/image.html#color-formats>`__
-section.
+list in the :ref:`Color formats <overview_image_color_formats>` section.
 
 Indexed colors
 --------------
@@ -67,6 +73,7 @@ The draw function can draw to any color format to which LVGL can render. Typical
 :cpp:enumerator:`LV_COLOR_FORMAT_RGB565`, :cpp:enumerator:`LV_COLOR_FORMAT_RGB888`,
 :cpp:enumerator:`LV_COLOR_FORMAT_XRGB888`, and :cpp:enumerator:`LV_COLOR_FORMAT_ARGB8888`.
 
+.. _lv_canvas_events:
 
 Events
 ******
@@ -74,10 +81,12 @@ Events
 No special events are sent by canvas objects. The same events are sent
 as for the
 
-See the events of the `Images </widgets/img>`__ too.
+See the events of the :ref:`lv_image` too.
 
 Learn more about :ref:`events`.
 
+.. _lv_canvas_keys:
+
 Keys
 ****
 
@@ -85,10 +94,14 @@ No *Keys* are processed by the object type.
 
 Learn more about :ref:`indev_keys`.
 
+.. _lv_canvas_example:
+
 Example
 *******
 
 .. include:: ../examples/widgets/canvas/index.rst
 
+.. _lv_canvas_api:
+
 API
 ***