On Wed, 15 Nov 2023 18:20:14 GMT, Marius Hanl <mh...@openjdk.org> wrote:
>> The change listener on caretPositionProperty() was not getting invoked on
>> replacing the content with same text as there was no change in caret
>> position. Since the textProperty invalidation sets the forward bias to true
>> by default, incorrect caret position was calculated when the same text was
>> replaced after clicking on the trailing edge of last character or empty
>> space in the TextField.
>>
>> Since caretShapeProperty invalidation listener gets invoked without changing
>> the caret position, updating the caretBiasProperty on this listener solves
>> the issue.
>>
>> Since the caret position value will be same when the caret is present after
>> the last character or before the last character, it can not be validated
>> using unit test.
>> The fix can be validated using MonkeyTester.
>> Steps to select TextField option in Monkey Tester.
>>
>> - Open the MonkeyTester app and select TextField from the left option pane.
>> - Select Short from Text selection option and click on the TextField to
>> bring it into focus.
>> - Select all using cmd(ctrl) + a and copy using cmd(ctrl) + c
>> - Click on empty space in the TextField after the present content.
>> - Select all again using the keyboard shortcut and paste using cmd(ctrl) + v
>> - The caret should be displayed after the last character. Without the fix
>> caret gets displayed before the last character.
>
> modules/javafx.controls/src/main/java/javafx/scene/control/skin/TextFieldSkin.java
> line 248:
>
>> 246: textNode.caretShapeProperty().addListener(observable -> {
>> 247:
>> caretPath.getElements().setAll(textNode.caretShapeProperty().get());
>> 248: if (caretPath.getElements().size() == 0 ||
>> caretPath.getElements().size() != 4) {
>
> I think this can be simplified to:
>
>
> if (caretPath.getElements().size() != 4) {
> // The caret pos is invalid.
> updateTextNodeCaretPos(control.getCaretPosition());
> } else {
> caretWidth = Math.round(caretPath.getLayoutBounds().getWidth());
> }
this might be problematic, as it uses undocumented aspect of
Text/Flow.caretShape(). the current implementation returns either a single
line, or two lines (moveto,lineto,moveto,lineto) in the case of split/dual
caret. But this may not be true in the future! If we add a directional
indicator to the caret this logic will break.
What we may need is to invent a new API possibly that gives us more information
about the caret - whether it's a single or split one, or whether it has a
directionality indicator, information about the adjacent text segments
(rtl,ltr), etc.
We can keep this logic for now, to be fixed once (and if) we add the more
detailed caret API.
-------------
PR Review Comment: https://git.openjdk.org/jfx/pull/1287#discussion_r1394656378
