Adds the `prompt` attribute to the `RichTextArea`, to be shown when the model
is `null` or empty.
To allow for greater flexibility, the type of this property is `Object`, and
there is an additional setter that accepts `Supplier<Object>`. The value of
the property, or the value provided by the `Supplier<Object>` is interpreted as
follows:
- `null`: the prompt is disabled
- `Node`: the node to be shown
- `String`: the text will be shown inside a `Label` with style `.prompt`
- `Object`: the toString() value will be shown similarly to the `String` value
The main idea is to have only one property and allow complex graphics to be
shown.
Example:
setPrompt("a");
setPrompt(this::getPrompt);
setPrompt(() -> new Object());
setPrompt(new Object());
setPrompt(null);
setPrompt((String)null);
setPrompt((Supplier)null);
---------
- [x] I confirm that I make this contribution in accordance with the [OpenJDK
Interim AI Policy](https://openjdk.org/legal/ai).
-------------
Commit messages:
- tests
- Merge branch 'master' into 8359862.prompt
- rich text area prompt
Changes: https://git.openjdk.org/jfx/pull/2237/files
Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=2237&range=00
Issue: https://bugs.openjdk.org/browse/JDK-8359862
Stats: 265 lines in 6 files changed: 262 ins; 1 del; 2 mod
Patch: https://git.openjdk.org/jfx/pull/2237.diff
Fetch: git fetch https://git.openjdk.org/jfx.git pull/2237/head:pull/2237
PR: https://git.openjdk.org/jfx/pull/2237
