how to get the group style

[skybook888]

i add same style on layer ，i can get the style on layer corectly
but if i add same style on a group,i can't get the style by get('objectEffects')

[LarryHangFan]

i add same style on layer ，i can get the style on layer corectly but if i add same style on a group,i can't get the style by get('objectEffects')
me too