About lvgl-Animation can't operate successfully

Description

when I operate the lvgl demo it made some problem

What MCU/Processor/Board and compiler are you using?

ESP32 board and use the PlatformIo to programming

What LVGL version are you using?

LVGL-V8.1

What do you want to achieve?

I wanna the animation can be used

What have you tried so far?

I had made it to strong conversion, but it also reported problem

Code to reproduce

Add a code snippet which can run in the simulator. It should contain only the relevant code that compiles without errors when separated from your main code base.

The code block(s) should be formatted like:
The following is the error report

Compiling .pio\build\esp32dev\src\main.cpp.o
src\main.cpp: In function 'void anim_x_cb(void*, int32_t)':
src\main.cpp:72:27: error: invalid conversion from 'void*' to '_lv_obj_t*' [-fpermissive]
         lv_obj_set_x(var,v);
                           ^
In file included from .pio\libdeps\esp32dev\lvgl/src/core/lv_obj.h:131:0,
                 from .pio\libdeps\esp32dev\lvgl/lvgl.h:35,
                 from src\Init.h:3,
                 from src\main.cpp:1:
.pio\libdeps\esp32dev\lvgl/src/core/lv_obj_pos.h:50:6: note:   initializing argument 1 of 'void lv_obj_set_x(_lv_obj_t*, lv_coord_t)'
 void lv_obj_set_x(struct _lv_obj_t * obj, lv_coord_t x);
      ^
Compiling .pio\build\esp32dev\lib756\lvgl\core\lv_obj_class.c.o
Compiling .pio\build\esp32dev\lib756\lvgl\core\lv_obj_draw.c.o
Compiling .pio\build\esp32dev\lib756\lvgl\core\lv_obj_pos.c.o
Compiling .pio\build\esp32dev\lib756\lvgl\core\lv_obj_scroll.c.o
Compiling .pio\build\esp32dev\lib756\lvgl\core\lv_obj_style.c.o
Compiling .pio\build\esp32dev\lib756\lvgl\core\lv_obj_style_gen.c.o
Compiling .pio\build\esp32dev\lib756\lvgl\core\lv_obj_tree.c.o
Compiling .pio\build\esp32dev\lib756\lvgl\core\lv_refr.c.o
Compiling .pio\build\esp32dev\lib756\lvgl\core\lv_theme.c.o
Compiling .pio\build\esp32dev\lib756\lvgl\draw\lv_draw_arc.c.o
*** [.pio\build\esp32dev\src\main.cpp.o] Error 1
Compiling .pio\build\esp32dev\lib756\lvgl\draw\lv_draw_blend.c.o

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static void anim_x_cb(void * var,int32_t v )

{

    lv_obj_set_x((lv_obj_t *)var,v);

}