image hierarchy issue in UGUI

Hi guys, I am newbie to Unity.

I created two empty sprites in hierarchy window under canvas One assign image by add “image component”, the other by script to add a mesh render.

No matter how I adjust the layer or hierarchy. The result is the “add image component” one always in front of the other. I can’t find the way to make the hierarchy right.

Thanks for the help.

another example of hierarchy issue is:

Gameobject player_red1 is always behind the white circle.
However, Gameobject player_red2 use the same adding component - “image”, assign image source method, has no issue to show in front.