On Mon, 13 Dec 2021 19:46:27 GMT, Martin Fox <d...@openjdk.org> wrote:

> The algorithm in `KeyCharacterCombination.match` relies on the call 
> `Toolkit.getKeyCodeForChar` which is difficult to implement correctly. It 
> defies the way most keyboard API’s work and no platform has got it right yet. 
> In particular the Mac and Linux implementations have to resort to a 
> brute-force approach which monitors keystrokes to learn the relationship 
> between keys and characters.
> 
> This PR introduces an alternative mechanism which directly asks the platform 
> whether a given key can generate a specific character. It also allows the 
> platform to attach identifying key information to each KeyEvent to make it 
> easier to answer the question (much, much easier).
> 
> This is mostly dumb plumbing. On the front-end there’s a new call 
> `View.notifyKeyEx` that takes an additional platform-specific `hardwareCode` 
> parameter. It also returns a boolean indicating whether the event was 
> consumed or not so I can fix JDK-8087863. If you want to follow the path 
> visit the files in this order:
> 
>       View.java
>       GlassViewEventHandler.java
>       TKSceneListener.java
>       Scene.java
> 
> The `KeyEvent` class has been expanded with an additional `hardwareCode` 
> member that can only be accessed internally. See KeyEvent.java and 
> KeyEventHelper.java.
> 
> On the back-end `KeyCharacterCombination.match` calls a new routine 
> `Toolkit.getKeyCanGenerateCharacter` which unpacks the `KeyEvent` information 
> and sends it on to the Application. The default implementation falls back to 
> the old `getKeyCodeForChar` call but platform specific Applications can send 
> it on to the native glass code.
> 
>       KeyCharacterCombination.java
>       Toolkit.java
>       QuantumToolkit.java
>       Application.java
>       GtkApplication.java
> 
> The glass code can use the `hardwareCode` to answer the question directly. It 
> also has enough information to fall back on the old `getKeyCodeForChar` logic 
> while also enabling the keypad (a common complaint is that Ctrl+’+’ only 
> works on the main keyboard and not the keypad, see JDK-8090275).
> 
> This PR improves the situation for key events generated by keystrokes. 
> Manually constructed key events won’t work any better or worse than they 
> already do. Based on the bug database I don't think this is an issue.

This pull request has been closed without being integrated.

-------------

PR: https://git.openjdk.org/jfx/pull/694

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