add the md files from the docs repo to start updating them to v8

docs/widgets/bar.md

@@ -0,0 +1,64 @@
+```eval_rst
+.. include:: /header.rst 
+:github_url: |github_link_base|/widgets/bar.md
+```
+# Bar (lv_bar)
+
+## Overview
+
+The bar object has a background and an indicator on it. The width of the indicator is set according to the current value of the bar. 
+
+Vertical bars can be created if the width of the object is smaller than its height.
+
+Not only end, but the start value of the bar can be set which changes the start position of the indicator.
+
+
+## Parts and Styles
+The Bar's main part is called `LV_BAR_PART_BG` and it uses the typical background style properties.
+
+`LV_BAR_PART_INDIC` is a virtual part which also uses all the typical background properties. 
+By default the indicator maximal size is the same as the background's size but setting positive padding values in `LV_BAR_PART_BG` will make the indicator smaller. (negative values will make it larger)
+If the *value* style property is used on the indicator the alignment will be calculated based on the current size of the indicator. 
+For example a center aligned value is always shown in the middle of the indicator regardless it's current size.
+
+## Usage
+
+### Value and range
+A new value can be set by `lv_bar_set_value(bar, new_value, LV_ANIM_ON/OFF)`.
+The value is interpreted in a range (minimum and maximum values) which can be modified with `lv_bar_set_range(bar, min, max)`.
+The default range is 1..100.
+
+The new value in `lv_bar_set_value` can be set with or without an animation depending on the last parameter (`LV_ANIM_ON/OFF`).
+The time of the animation can be adjusted by `lv_bar_set_anim_time(bar, 100)`. The time is in milliseconds unit.
+
+It's also possible to set the start value of the bar using `lv_bar_set_start_value(bar, new_value, LV_ANIM_ON/OFF)`
+
+### Modes
+The bar can be drawn symmetrical to zero (drawn from zero, left to right), if it's enabled with `lv_bar_set_type(bar, LV_BAR_TYPE_SYMMETRICAL)`.
+
+## Events
+Only the [Generic events](../overview/event.html#generic-events) are sent by the object type.
+
+Learn more about [Events](/overview/event).
+
+## Keys
+No *Keys* are processed by the object type.
+
+Learn more about [Keys](/overview/indev).
+
+## Example
+
+```eval_rst
+
+.. include:: /lv_examples/src/lv_ex_widgets/lv_ex_bar/index.rst
+
+```
+
+## API
+
+```eval_rst
+
+.. doxygenfile:: lv_bar.h
+  :project: lvgl
+
+```