keepAtBottom doesn't work if the size of the inner element doesn't change

Scenario: I have a chatcomponent that shows only the latest 50 chats in a conversation. If all my chat lines have the same height and a new line is added (which causes the previous line 0 to disappear and adds a new line on index 49), the component doesn’t scroll down.

I’ve tried editing this line so that it compares this.props.children with prevProps.children, but doesn’t always work because for some reason the reachedBottomOnCurrentRender evaluates to false…

Any idea?

Currently I just copied your code and removed the reachedBottomOnCurrentRender which still makes the component behave as expected, so not sure what the use of that check is?

[Neglexis]

@rommguy Consider it done!

[rommguy]

@Neglexis Thanks for showing me this bug. The fix is in version 2.0.2 I’ve added a failing test, you are welcome to review it.

I used your code to fix the issue with one change - I think comparing props.children isn’t the best way to check what we need - if the render is a result of an external change or not. Someone could cache the props from outside, and pass the same reference to them, and this will fail. Instead I created a variable called “externalRender”, assigned true in willReceiveProps (only invoked when render is caused by external action), and assigned false at the end of didUpdate This way I can enforce the bottom position as long as the render is a result of an external change, regardless of size changes in the content.