使用PanResponder向上滑动时使View呈现

Question

I am able to change the position (swipe up) of my View accordingly with PanResPonder. The problem is during the swipe motion, the content of the View being dragged for the swipe do not render.

I tried using flexGrow:1 and flex:1 so as the View enlarge with the swipe, the View would be getting filled by content.

I know there a few libraries out there for swipes but I think this is fairly doable without library. Thanks in advance cheers.

Answer 1

It really depends on your approach there. First things first.

You have to understand about JS Bridge and Native on react-native. The JSBridge is single-treaded and all the fired renders go through there. It means you can easily get dropped on FPS if you do not take it into account. The Native, well, is native code running, thats all.

To have performant app, you have to keep the passes over the bridge to a minimun.

The PanResponder touches happen on the native side, while the component renders use the bridge. You should put some code there, but i would bet that the problem is with too many renders happening and the JS Bridge gets overloaded.

Also try to use Direct Manipulation ( https://facebook.github.io/react-native/docs/direct-manipulation.html ) to avoit rendering one entire tree and perform it on the native side.