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.
-------------
Commit messages:
- New KeyCharacterCombination implementation
Changes: https://git.openjdk.java.net/jfx/pull/694/files
Webrev: https://webrevs.openjdk.java.net/?repo=jfx&pr=694&range=00
Issue: https://bugs.openjdk.java.net/browse/JDK-8273743
Stats: 290 lines in 16 files changed: 243 ins; 10 del; 37 mod
Patch: https://git.openjdk.java.net/jfx/pull/694.diff
Fetch: git fetch https://git.openjdk.java.net/jfx pull/694/head:pull/694
PR: https://git.openjdk.java.net/jfx/pull/694
