status-im/react-native
2
0
Fork 0
mirror of https://github.com/status-im/react-native.git synced 2025-01-26 17:30:25 +00:00
Code Issues Projects Releases Wiki Activity

Fix deltatime calculation.

Browse Source 
Summary:
This is necessary to fix an extraneous warning when a VirtualizedList is constructed on the first frame.

On the first frame, the dt is huge (ie, time since epoch).
On the second frame (which may legitimately be slow as a result of a lot to render), it will then assume there were two consecutive slow frames, and print a warning:
  "VirtualizedList: You have a large list that is slow to update..."
Closes https://github.com/facebook/react-native/pull/14393

Differential Revision: D5210467

Pulled By: sahrens

fbshipit-source-id: 2e79218c3d66a4a9df4884f328a125047ef264ed
This commit is contained in:
Mike Lambert 2017-06-08 12:14:12 -07:00 committed by Facebook Github Bot
parent 62b20ce582
commit 5840a9051d
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
Libraries/Lists/VirtualizedList.js
View File

@ -734,7 +734,9 @@ class VirtualizedList extends React.PureComponent<OptionalProps, Props, State> {
const visibleLength = this._selectLength(e.nativeEvent.layoutMeasurement);
const contentLength = this._selectLength(e.nativeEvent.contentSize);
const offset = this._selectOffset(e.nativeEvent.contentOffset);
const dt = Math.max(1, timestamp - this._scrollMetrics.timestamp);
const dt = this._scrollMetrics.timestamp
? Math.max(1, timestamp - this._scrollMetrics.timestamp)
: 1;
if (dt > 500 && this._scrollMetrics.dt > 500 && (contentLength > (5 * visibleLength)) &&
!this._hasWarned.perf) {
infoLog(