Update drawing on demand if properties change and not on every drawing cycle. This should reduce the overhead to access properties from the view / layer for the drawing parameters.
- Add locking to _linkAttributeValueAtPoint:attributeName:range:inAdditionalTruncationMessage:forHighlighting: as we access the attributed text in there
- Add locking to touchesBegan:withEvent: as we are accessing the [ASTextKitRenderer firstVisibleRange]
- Add locking for highlightStyle
- Move accessing delegate property access to instance variable access
The crash happens in the placeholderImage of ASTextNode. The node is not visible in the time it try to get the `placeholderImage` and so the `visibleRange` has count 0 and a crash happens while accessing the first object of an empty array.
- Deprecate attributedString in ASTextNode in favor of attributedText to be aligned with UILabel
- Deprecate truncationAttributedString in ASTextNode in favor of truncationAttributedText to be aligned with attributedText
- Refactor naming of ASEnvironmentCollection to ASEnvironmentState
- Remove struct pointers
- Move ASEnvironmentStatePropagation to a enum class
- Move merge functions to pure functions
- Move ASLayoutOptionsForwarding and ASLayoutableExtensibility into ASLayoutSpec and ASDisplayNode
- Remove ASLayoutableSetValuesForLayoutable and move into explicit classes (ASDisplayNode, ASTextNode)
1) cache the scale in the font adjuster. The adjuster will be dealloc'ed when the renderer that owns it is dealloc'ed (or invalidated). Until that time we can trust the scale that the adjuster has computed.
2) When measuring line count, make sure that we are not bounding the height of the container's size. This will cause the wrong number of lines to be returned.
3) Instead of setting the ascender/descender on an ASTextNode when an attributed string is added, wait until after the renderer calculates size. This way, if there is any need to scale the font to fit we can apply that scale to the ascender/descender.
A text node's renderer is often invalidated. Save the renderer's constrained size locally so we can use it when creating a new renderer after invalidation.
Was running into issues where the scale factor would get cleared when setting a new atributedString on a textNode.
I was clearing out the currentScaleFactor when setting an attributedString into a textNode. It appears that `_calculateSize` isn't always called when setting a new string into a ASTextNode. It can be the case that only `drawInContext:bounds:` is called. With _currentScaleFactor cleared out the renderer that calls`drawInContext...` was being called with a scaleFactor of 0.
It could be the case that the fix could be to remove the clearing of `currentScaleFactor` from `setAttributedString`, but this seems like a safer fix to me. It does, however, require an extra run through the font adjuster when enabled.
* Added a member to `ASTextKitAttributes` that is an optional delegate to the struct's NSLayoutManager.
* Changed ASTextNode to set this delegate to an instance of ASTextNodeWordKerner.
* Updated init method of `ASTextKitContext` to take an optional NSLayoutManager delegate
* Added the files in TextKit folder to the public headers (so we can include ASTextNodeTypes.h)
This patch switches to instance methods of draw and display for
ASTextNode and ASImageNode to attempt to increase their performance.
It also fixes some thread safety issues in ASImageNode which appear
to have been regressions (though probably not hit very often).
And it sets up work for allowing modification of CGContexts before
and after a node's contents are drawn.
Actually it is possible that truncated string is longer then original
string.
For example, original string:
```
hello
this is
very long
message here
and there
```
with maximumNumberOfLines=4, truncationAttributedString = ' ...' and
additionalTruncationMessage = 'read more'
will give
```
hello
this is
very long
message here ... read more
```
So `[attributedString attribute:attributeName atIndex:characterIndex
longestEffectiveRange:&range inRange:visibleRange]` will crash.
