Bug ID: JDK-8100148 Add RTL support to Text node

Type: Sub-task
Component: javafx
Sub-Component: graphics
Affected Version: 8

Priority: P2
Status: Closed
Resolution: Fixed

Submitted: 2012-11-09
Updated: 2015-06-16
Resolved: 2012-12-26

JDK 8
8Fixed

The Text class should override getEffectiveNodeOrientation() to return a value based on the content's natural direction (using BIDI algorithm), rather than assume LTR by default.  This assumes that getEffectiveNodeOrientation() can be made non-final -- or better yet, be turned into a read-only property so that text input controls can listen to changes that are triggered by user input.

If the content is empty or contains only direction-neutral characters, then the effective orientation should be based on the nodeOrientation property, but only then.

If it is absolutely necessary to let applications set the orientation explicitly, then Text would need the ability to track whether nodeOrientation is set explicitly on the node. This is not possible currently. Note that it would not be enough to rely on nodeOrientation being INHERIT as that could also be used as an explicit value.

Verified on 8.0b114
05-11-2013
http://jfxsrc.us.oracle.com/javafx/8.0/scrum/graphics/rt-closed/rev/8323a36cbdf1 fixing final part
26-12-2012
Text needs to map horizontal in/out values. Since Text does not mirror it has to translate the coordinates by itself, this should affect any x in or out relative to the node: caret shape, selection shape, hit test.
07-12-2012
fixed http://jfxsrc.us.oracle.com/javafx/8.0/scrum/graphics/rt-closed/rev/7fe4eda3c61c http://jfxsrc.us.oracle.com/javafx/8.0/scrum/graphics/rt/rev/ef5f81064000
29-11-2012
the first patch has a bug in TextLayout when orientation is changed dynamically. This patch fixes it.
21-11-2012
Thanks for reviewing I will wait for RT-26140 so I can push the code to without the impl_transformChanged hack. Note: I will need to put the same code in TextFlow.
21-11-2012
Patches look good.
21-11-2012
Temporary patch for rt.closed
21-11-2012
temporary patch for rt
21-11-2012
For the record, an application can add a bidi sniffer and change the nodeOrientation and/or textAlignment using something like the following. Note that this can be a bit heavy if the text string is large or if the content changes frequently. text.nodeOrientationProperty().bind(new ObjectBinding<NodeOrientation>() { { bind(text.textProperty()); } @Override protected NodeOrientation computeValue() { Bidi bidi = new Bidi(text.getText(), (textParent.getEffectiveNodeOrientation() == NodeOrientation.LEFT_TO_RIGHT) ? Bidi.DIRECTION_DEFAULT_LEFT_TO_RIGHT : Bidi.DIRECTION_DEFAULT_RIGHT_TO_LEFT); return (bidi.baseIsLeftToRight() ? NodeOrientation.LEFT_TO_RIGHT : NodeOrientation.RIGHT_TO_LEFT); } });
20-11-2012
The going to do the work part in scene, part in prism. I'll prepare a patch and send it to you for review hopefully today.
20-11-2012
That's fine. I think that all we need for now is to override isAutomaticallyMirrored() and to match textAlignment with nodeOrientation (using a listener, not a bind). I can take ownership of this if you want.
20-11-2012
My vote is don't sniff for now. Review sniffing in a later JIRA.
20-11-2012
Leif, have we decided how the Text node should work ? Always sniff Never sniff My take is to never sniff Whichever decide we can always add API in the future to customize this behavior if needed.
20-11-2012
See also RT-26140, RT-26141 and RT-26142.
12-11-2012
Filed RT-26215
12-11-2012
is that new ? Are we keeping all the API: effecitveOrientation(), isAutomaticallyMirrored(), getNodeOrientation(), and setNodeOrientation(). Can we just called isMirrored() ? can we remove effectiveOrientation() and (one day) replace it by generic version that can take any property, similar to javascript window.getComputedStyle, see https://developer.mozilla.org/en-US/docs/DOM/window.getComputedStyle
12-11-2012
Text should just implement the following to avoid mirroring: @Override public boolean isAutomaticallyMirrored() { return false; }
12-11-2012
Yes, that is correct, if the application sets orientation directly on text node that is what happen. The difference between Text and other Nodes is what happen when the orientation is not set on it directly. Other Nodes will inherit from the parent. Text will determine the orientation based on its current text content (text node orientation equals direction of the first char with strong directionality). If the text content is empty (or all neutral chars), the orientation is inherit from the parent. effective orientation is what it means to any other node. text alignments is based on the effective orientation and it is reversed for RTL. In the implementation the text node is never mirrored. Not sure how this can be implemented using current design. I suspect it can't because getEffectiveOrientation() down in Node is what is used to decide mirroring ?
12-11-2012
It was my understanding that the application program needs to say up front which text nodes are expected to be handling RTL data. Is this wrong?
12-11-2012

Blocks :	JDK-8100130 - Add RTL support to Label / Labeled
Blocks :	JDK-8102169 - Node Orientation - API issue: Should effective orientation be a property?
Blocks :	JDK-8125260 - ScrollPane RTL orientation, Text in the ScrollPane got mirrored.
Relates :	JDK-8100141 - Add RTL support to TextField / TextArea / PasswordField
Relates :	JDK-8116555 - Node Orientation - API issue: Should isAutomaticallyMirrored() be protected?
Relates :	JDK-8099289 - Support component orientation in common UI controls
Relates :	JDK-8102424 - Node Orientation - API issue: Is isAutomaticallyMirrored() named properly?
Relates :	JDK-8119721 - Node Orientation - TextArea doesn't scroll "right" properly