Summary:
This diff implement the CSS z-index for React Native iOS views. We've had numerous pull request for this feature, but they've all attempted to use the `layer.zPosition` property, which is problematic for two reasons:
1. zPosition only affects rendering order, not event processing order. Views with a higher zPosition will appear in front of others in the hierarchy, but won't be the first to receive touch events, and may be blocked by views that are visually behind them.
2. when using a perspective transform matrix, views with a nonzero zPosition will be rendered in a different position due to parallax, which probably isn't desirable.
See https://github.com/facebook/react-native/pull/7825 for further discussion of this problem.
So instead of using `layer.zPosition`, I've implemented this by actually adjusting the order of the subviews within their parent based on the zIndex. This can't be done on the JS side because it would affect layout, which is order-dependent, so I'm doing it inside the view itself.
It works as follows:
1. The `reactSubviews` array is set, whose order matches the order of the JS components and shadowView components, as specified by the UIManager.
2. `didUpdateReactSubviews` is called, which in turn calls `sortedSubviews` (which lazily generates a sorted array of `reactSubviews` by zIndex) and inserts the result into the view.
3. If a subview is added or removed, or the zIndex of any subview is changed, the previous `sortedSubviews` array is cleared and `didUpdateReactSubviews` is called again.
To demonstrate it working, I've modified the UIExplorer example from https://github.com/facebook/react-native/pull/7825
Reviewed By: javache
Differential Revision: D3365717
fbshipit-source-id: b34aa8bfad577bce023f8af5414f9b974aafd8aa
Summary:New prop `hitSlop` allows extending the touch area of Touchable components. This makes it easier to touch small buttons without needing to change your styles.
It takes `top`, `bottom`, `left`, and `right` same as the `pressRetentionOffset` prop. When a touch is moved, `hitSlop` is combined with `pressRetentionOffset` to determine how far the touch can move off the button before deactivating the button.
On Android I had to add a new file `ids.xml` to generate a unique ID to use for the tag where I store the `hitSlop` state. The iOS side is more straightforward.
terribleben worked on the iOS and JS parts of this diff.
Fixes#110
Closes https://github.com/facebook/react-native/pull/5720
Differential Revision: D2941671
Pulled By: androidtrunkagent
fb-gh-sync-id: 07e3eb8b6a36eebf76968fdaac3c6ac335603194
shipit-source-id: 07e3eb8b6a36eebf76968fdaac3c6ac335603194
Summary:
Currently, the system for mapping JS event handlers to blocks is quite clean on the JS side, but is clunky on the native side. The event property is passed as a boolean, which can then be checked by the native side, and if true, the native side is supposed to send an event via the event dispatcher.
This diff adds the facility to declare the property as a block instead. This means that the event side can simply call the block, and it will automatically send the event. Because the blocks for bubbling and direct events are named differently, we can also use this to generate the event registration data and get rid of the arrays of event names.
The name of the event is inferred from the property name, which means that the property for an event called "load" must be called `onLoad` or the mapping won't work. This can be optionally remapped to a different property name on the view itself if necessary, e.g.
RCT_REMAP_VIEW_PROPERTY(onLoad, loadEventBlock, RCTDirectEventBlock)
If you don't want to use this mechanism then for now it is still possible to declare the property as a BOOL instead and use the old mechanism (this approach is now deprecated however, and may eventually be removed altogether).
Summary:
RCTCache had really bad insertion performance when the cache was full due to having to LRU-sort the entries. This was making color
animations very slow.
I've fixed this in two ways:
1) by removing the sort and doing a linear search to remove old entries, which changes insertion perf to O(n) in the worst case instead of O(n log n) or even (n2).
2) by reducing the size of the color cache to 128 from 1024, which should be fine for normal use, without penalising animation performance.
Separately, border colors were not being retained, which caused crashes when the color cache was cleared. I've fixed that by retaining the border colors inside RCTView.
Nick Lockwood
Jesse Ruder
David Aurelio
Georgiy Kassabli
Alex Akers
Tadeu Zagallo