RFR: 8090547: Allow for transparent backgrounds in WebView [v4]

[Jose Pereda]

On Wed, 25 Aug 2021 23:49:10 GMT, Kevin Rushforth <kcr at openjdk.org> wrote:

>> Jose Pereda has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Update cssref.html
>
> modules/javafx.web/src/main/java/javafx/scene/web/WebView.java line 733:
> 
>> 731:                     Color color = get();
>> 732:                     page.setBackgroundColor(color != null ? color.hashCode() :
>> 733:                             DEFAULT_PAGE_FILL.hashCode());
> 
> This is relying on an undocumented, implementation detail. The current implementation of `Color::hashCode` happens to do what you want, but it is not specified. It seems safer to create a utility method to do this.

Yes, that makes total sense. 

In fact, there was also the need to add a new [method](https://github.com/openjdk/jfx/pull/563/files#diff-b80bc720bf639cde38c5197a7619561221abcd34fb9ff7a933f4b932a1f36735R2579) in `WebPage` to read back the color from the int value, so I was thinking that it would be better to add a new method to `WebPage` like:


public void setBackgroundColor(Color backgroundColor) {
     int int32Color = WebPage.getBackgroundInt32Color(backgroundColor);
     setBackgroundColor(int32Color);
}

private static int getBackgroundInt32Color(Color color) {
// implementation similar to Color::hashCode
}

and from webView we could simply do:

page.setBackgroundColor(color);


Thoughts?

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

PR: https://git.openjdk.java.net/jfx/pull/563