问题
I was searching for method similar to OnBecameVisible for Canvas UI. MonoBehaviour.OnBecameVisible()
So that I can load and unload image resources based on requirements. But I can't able to find anything useful in this. I have this kind of page exist which contains 250+ flowers information so I have to manage my texture resources for this.
If I disable Image component then page loaded correctly in game otherwise game get crashed in iPhone device when I load this page because of too much graphics memory requirements.
So for managing resources loading and unloading, I need some way.
回答1:
There is no direct solution provided by Unity at the moment. But since the visible area is rectangular and related to screen space, you can easily check if your element contained in it.
Here is some post from forums about a helper script and its usage about this situation which should be able to solve your problem: https://forum.unity.com/threads/test-if-ui-element-is-visible-on-screen.276549/#post-2978773
来源：https://stackoverflow.com/questions/47314314/onbecomevisible-for-canvas-ui-objects