Summary:
public
I was looking into the missing panels at the bottom of the <ListView> - Grid Layout example, and found that it was caused by several problems, some in the example and some in ListView itself.
The first problem seemed to be a bug in the `_getDistanceFromEnd()` method, which calculates whether the ListView needs to load more content based on the distance of the visible content from the bottom of the scrollview. This was previously using the function
Math.max(scrollProperties.contentLength, scrollProperties.visibleLength) - scrollProperties.visibleLength - scrollProperties.offset
to calculate the amount the user could scroll before they run out of content. This sort-of works in most cases because `scrollProperties.contentLength` is usually longer than `scrollProperties.visibleLength`, so this would generally evaluate to
scrollProperties.contentLength - scrollProperties.visibleLength - scrollProperties.offset
which meant that it would be positive as long as there was content still to be displayed offscreen, and negative when you reached the end of the content. This logic breaks down if `contentLength` is less than `visibleLength`, however. For example, if you have 300pts of content loaded, and your scrollView is 500pts tall, and your scroll position is zero, this evaluates to
Math.max(300, 500) - 500 - 0 = 0
In other words, the algorithm is saying that you have zero pts of scroll content remaining before you need to reload. But actually, the bottom 200pts of the screen are empty, so you're really 200pts in debt, and need to load extra rows to fill that space. The correct algorithm is simply to get rid of the `Math.max` and just use
scrollProperties.contentLength - scrollProperties.visibleLength - scrollProperties.offset
I originally thought that this was the cause of the gap, but it isn't, because ListView has `DEFAULT_SCROLL_RENDER_AHEAD = 1000`, which means that it tries to load at least 1000pts more content than is currently visible, to avoid gaps. This masked the bug, so in practice it wasn't causing an issue.
The next problem I found was that there is an implict assumption in ListView that the first page of content you load is sufficient to cover the screen, or rather, that the first _ second page is sufficient. The constants `DEFAULT_INITIAL_ROWS = 10` and `DEFAULT_PAGE_SIZE = 1`, mean that when the ListView first loads, the following happens:
1. It loads 10 rows of content.
2. It checks if `_getDistanceFromEnd() < DEFAULT_SCROLL_RENDER_AHEAD` (1000).
3. If it is, it loads another `DEFAULT_PAGE_SIZE` rows of content, then stops.
In the case of the ListView Grid Layout example, this meant that it first loaded 10 cells, then loaded another 1, for a total of 11. The problem was that going from 10 to 11 cells isn't sufficient to fill the visible scroll area, and it doesn't change the `contentSize` (since the cells wrap onto the same line), and since ListView doesn't try to load any more until the `contentSize` or `scrollOffset ` changes, it stops loading new rows at that point.
I tried fixing this by calling `_renderMoreRowsIfNeeded()` after `_pageInNewRows()` so that it will continue to fetch new rows until the `_getDistanceFromEnd()` is less than the threshold, rather than stopping after the first page and waiting until the `contentSize` or `scrollOffset` change, but although this solves the problem for the Grid Layout example, it leads to over-fetching in the more common case of a standard row-based ListView.
In the end, I just increased the `pageSize` to 3 for the Grid Layout example, which makes more sense anyway since loading a page that is not a multiple of the number of cells per row confuses the `_renderMoreRowsIfNeeded` algorithm, and leads to gaps at the bottom of the view.
This solved the problem, however there was still a "pop-in" effect, where the additional rows were paged in after the ListView appeared. This was simply a misconfiguration in the example itself: The default of 10 rows was insufficient to fill the screen, so I changed the `initialListSize` prop to `20`.
Reviewed By: javache
Differential Revision: D2911690
fb-gh-sync-id: 8d6bd78843335fb091e7e24f7c2e6a416b0321d3
shipit-source-id: 8d6bd78843335fb091e7e24f7c2e6a416b0321d3
Summary:
The THUMB_URLS is following the older syntax.
Fixed THUMBNAILS to follows require Syntax. And now you see the thumbnails appearing in the Sample app.
Closes https://github.com/facebook/react-native/pull/4995
Reviewed By: svcscm
Differential Revision: D2796019
Pulled By: nicklockwood
fb-gh-sync-id: c7be50d4dea73fc383db1c6b5a6afa7444505889
Summary: Fixed THUMB_URLS in examples. Have kept a local copy of images as decided. Refer #4159 for more details.
Closes https://github.com/facebook/react-native/pull/4178
Reviewed By: svcscm
Differential Revision: D2663613
Pulled By: nicklockwood
fb-gh-sync-id: f2410c4a5df1736bb12afa393539b00e8dc5dbbf
Summary:
Because we don't want to integrate Animated inside of the core of React, we can only pass Animated.Value to styles of <Animated.View>. TouchableOpacity unfortunately used cloneElement. This means that we should have asked every single call site to replace their children to Animated.View. This isn't great.
The other solution is to stop using cloneElement and instead wrap the children inside of an <Animated.View>. This has many advantages:
- We no longer use cloneElement so we're no longer messing up with elements that are not our own.
- Refs are now working correctly for children elements
- No longer need to enforce that there's only one child and that this child is a native element
The downside is that we're introducing a <View> into the hierarchy. Sadly with CSS there is no way to have a View that doesn't affect layout. What we need to do is to remove the inner <View> and transfer all the styles to the TouchableOpacity. It is annoying but fortunately a pretty mechanical process.
I think that having a wrapper is the best solution. I will investigate to see if we can make wrappers on TouchableHighliht and TouchableWithoutFeedback as well.
**Upgrade Path:**
If the child is a View, move the style of the View to TouchableOpacity and remove the View itself.
```
<TouchableOpacity onPress={...}>
<View style={...}>
...
</View>
</TouchableOpacity>
-->
<TouchableOpacity onPress={...} style={...}>
...
</TouchableOpacity>
```
If the child is an Image or Text, on all the examples at Facebook it worked without any change. But it is a great idea to double check them anyway.
- [Touchable] Change default `activeOpacity` to 0.2 to match iOS | James Ide
- [ReactNative] Normalize name for examples | Christopher Chedeau
- [ReactNative] Added support for 3 digit hex colors | Arthur Lee
- [react-packager] Fix EISDIR error | Amjad Masad
- make renderError and renderLoading props optional for WebView | Don Yu
- [ReactNative] Clean up no longer needed reference to NavigationBarClass | Philipp von Weitershausen
- [TextInput] returnKeyType, enablesReturnKeyAutomatically, secureTextEntry, more keyboardTypes | Tadeu Zagallo
- [ReactNative] PropTypes for NavigationBars | Philipp von Weitershausen
- Changed LayoutAnimation to use ms instead of seconds for consistency | Nick Lockwood
- Better date support | Nick Lockwood
- Renamed throttleScrollCallbackMS to scrollEventThrottle | Nick Lockwood
- Fixed threading issues in RCTImageDownloader | Nick Lockwood
- [iOS][Assets]: Cleaning up more 1x png from Libraries | Radu Marin
- [ReactNative][docs] LinkingIOS | Tadeu Zagallo
- Fixing TouchableOpacity and TouchableHighlight documentation | Ben Alpert
- [react-native] Add React.addons.createFragment | Ben Alpert
- [ReactNative] Use deprecated ix in TabBarExample | Amjad Masad
- [ReactNative] Expanded license on obj-c files | Christopher Chedeau
- [ReactNative] Expanded license on js files | Christopher Chedeau
- [ReactNative] Fix React Devtools integration | Alex Kotliarskyi
- [Text] Account for font leading so descenders are not clipped | James Ide
- [ReactNative] Expanded license on js packager files | Christopher Chedeau
- more UIExplorer flow | Basil Hosmer
- [react-packager] Pick up package changes while running | Amjad Masad
- Added a graph view and a ReactNative metric that displays current queue and execution time for the JS thread. | Bryce Redd
- [ReactNative] Add NativeModules and DeviceEventEmitter to react-native exports | Alex Kotliarskyi
- [ReactNative] Fix throttle warning and warn in callback instead of render | Christopher Chedeau
- [react-packager][streamline oss] Remove react-page-middleware | Amjad Masad
- [ReactNative] Turn on perf measurement around a group feed load | Jing Chen
- Implemented Layout animations | Nick Lockwood
- [ReactNative] Revert D1815137 - avoid dropping touch start on missing target | Eric Vicenti
- Moved RKPOPAnimationManager into FBReactKitComponents | Nick Lockwood
- Extracted RKAnimationManager | Nick Lockwood
Nick Lockwood
Satvik Jagannath
Olivier Notteghem
Der-Nien Lee
Christopher Chedeau
Spencer Ahrens
Tadeu Zagallo