anim timeline example with callback setters

lv_example_anim_timeline_1.py

#!/opt/bin/lv_micropython -i

import sys
sys.path.append('') # See: https://github.com/micropython/micropython/issues/6419

import time
import lvgl as lv
import display_driver_utils

lv.init()
driver = display_driver_utils.driver()

def event_handler(e):
    # print("event_handler")

    obj = e.get_target()

    if obj == btn:
        playback = btn.has_state(lv.STATE.CHECKED)
        lv.anim_timeline_t.start(anim_timeline, playback)

    elif obj == slider:
        progress = slider.get_value()
        lv.anim_timeline_t.set_progress(anim_timeline, progress)
            
#
# Create an animation timeline
#
par = lv.scr_act()
par.set_flex_flow(lv.FLEX_FLOW.ROW)
par.set_flex_align(lv.FLEX_ALIGN.SPACE_AROUND, lv.FLEX_ALIGN.CENTER, lv.FLEX_ALIGN.CENTER)

btn = lv.btn(par)
btn.add_event_cb(event_handler, lv.EVENT.VALUE_CHANGED, None)
btn.add_flag(lv.obj.FLAG.IGNORE_LAYOUT)
btn.add_flag(lv.obj.FLAG.CHECKABLE)
btn.align(lv.ALIGN.BOTTOM_LEFT, 0, 0)

slider = lv.slider(par)
slider.add_event_cb(event_handler, lv.EVENT.VALUE_CHANGED, None)
slider.add_flag(lv.obj.FLAG.IGNORE_LAYOUT)
slider.align(lv.ALIGN.BOTTOM_RIGHT, -20, -20)
slider.set_range(0, 65535)

obj1 = lv.obj(par)
obj2 = lv.obj(par)
obj3 = lv.obj(par)

obj_width = obj1.get_style_width(0)
obj_height = obj1.get_style_height(0)

anim_timeline = [lv.anim_timeline_t({"start_time" : 0,
                    "var" : obj1,
                    # "exec_cb" : set_width,
                    "start_value" : 0,
                    "end_value" : obj_width,
                    "duration" : 300,
                    # "path_cb" : lv.anim_t.path_overshoot
                    }),
                 lv.anim_timeline_t({
                     "start_time" : 0,
                     "var" : obj1,
                     # "exec_cb" : set_height,
                     "start_value" : 0,
                     "end_value" : obj_height,
                     "duration" : 300,
                     # "path_cb" : lv.anim_t.path_ease_out
                     }),
                 lv.anim_timeline_t({
                     "start_time" : 200,
                     "var" : obj2,
                     # "exec_cb" :  set_width,
                     "start_value" : 0,
                     "end_value" : obj_width,
                     "duration" : 300,
                     # "path_cb" : lv.anim_t.path_overshoot
                     }),
                 lv.anim_timeline_t({
                     "start_time": 200,
                     "var" : obj2,
                     # "exec_cb" : set_height,
                     "start_value" : 0,
                     "end_value" : obj_height,
                     "duration" : 300,
                     # "path_cb" : lv.anim_t.path_ease_out
                     }),
                 lv.anim_timeline_t({
                     "start_time" : 400,
                     "var" : obj3,
                     # "exec_cb" : set_width,
                     "start_value" : 0,
                     "end_value" : obj_width,
                     "duration" :  300,
                     # "path_cb" :  lv.anim_t.path_overshoot
                     }),
                 lv.anim_timeline_t({
                     "start_time" : 400,
                     "var" : obj3,
                     # "exec_cb" :  set_height,
                     "start_value" : 0,
                     "end_value" : obj_height,
                     "duration" :  300,
                     # "path_cb" : lv.anim_t.path_ease_out
                     }),
                 lv.anim_timeline_t({
                     "start_time" : -1})]


anim_timeline[0].set_exec_cb(lambda a,v: obj1.set_width(v))
anim_timeline[0].set_path_cb(lv.anim_t.path_overshoot)
anim_timeline[1].set_exec_cb(lambda a,v: obj1.set_height(v))
anim_timeline[1].set_path_cb(lv.anim_t.path_ease_out)
anim_timeline[2].set_exec_cb(lambda a,v: obj2.set_width(v))
anim_timeline[2].set_path_cb(lv.anim_t.path_overshoot)
anim_timeline[3].set_exec_cb(lambda a,v: obj2.set_height(v))
anim_timeline[3].set_path_cb(lv.anim_t.path_ease_out)
anim_timeline[4].set_exec_cb(lambda a,v: obj3.set_width(v))
anim_timeline[4].set_path_cb(lv.anim_t.path_overshoot)
anim_timeline[5].set_exec_cb(lambda a,v: obj3.set_height(v))
anim_timeline[5].set_path_cb(lv.anim_t.path_ease_out)