This attribute is written by Xlsx Writer, using the `tooltip` attribute, introduced by PR #904 in 2019. It is ignored by Excel, but may be used by Google Sheets (see issue #807). If it is used by anyone, it should be supported by Xlsx Reader, and exist as its own attribute in the `Hyperlink` class. Writer will continue to use tooltip if the new attribute isn't set.
Theme colors subject to tints occur in the wild, and should not be targeted by this PR. Our use case is an unmodified Theme color. There is probably a decent case to be made for adding a Tint property to Color, but that can come later if desired.
`Color::setHyperlinkTheme` will now try to fill in `rgb` as well as `theme` if it can locate an appropriate value in the Spreadsheet Theme. This will permit non-Xlsx formats to at least duplicate the color that Xlsx uses for hyperlinks.
Setting `Color::rgb\argb` will reset `theme` to none. If you want to use both, do rgb first, then theme. This will, I hope, avoid surpises for end-users.
Fix#1632. Excel automatically supplies a style for cells which contain hyperlinks (e.g. underlined, and blue text changing to purple after the link has been followed). PhpSpreadsheet cannot handle the style automatically. The user can, with some effort, specify a style for the cell which mimics Excel's choice (except for the color change after following).
Examining a sheet with a hyperlink created through Excel, it appears that Excel creates 3 different entries in styles.xml, one for cellStyleXfs, one for cellXfs, and one for cellStyles. It is difficult for me to figure out how they interrelate. This is especially so since PhpSpreadsheet outputs only 1 entry (for the default style) for each of cellStyles and cellStyleXfs. However, it appears that only the cellXfs entry is required, and, when it specifies a font whose color specifies `theme="10"` rather than an rgb value, the style works as expected.
In order to implement this, it is necessary to add a `theme` property, with setter and getter, to Style/Color. There are 12 possible values for theme, 0-11 representing 0=dk1 1=lt1 2=dk2 3=lt2 4-9=accent1-6 10=hlink 11=folHlink. This PR is mainly to allow the use of hlink, but the others are also usable if a use case arises for them. If a theme is set for Color, Xlsx Writer will use the theme rather than rgb when generating the color xml. Other writers will continue to use rgb rather than theme, so there is a use case for setting both if you want to generate both Xlsx and some other format.
The `theme` property will, for now, be ignored except for Font. There is probably a case to be made for using it for Fill, and maybe for Border and other areas that I haven't yet considered. I will wait for someone to make that case before adding those.
In order to make it as easy as possible to use this, a method `setHyperlinkTheme` is added to both Style/Color and Style/Font. The one in Color sets `theme` to the appropriate value. The one in Font calls the one in Color, and also sets `underline` on (this will be honored by other writers in addition to Xlsx).
Samples which use hyperlinks are updated to use `setHyperlinkTheme`. So is `Reader\Xlsx\HyperlinkTest`, with appropriate tests added.
While we might never be able to have 100% of our code strict, we can at
the very least do it for all of our tests. This ensures that our tests
are using our API with the types as intended by the test author, and not
silently be cast to what our API requires.
Fix#2389. Hyperlinks referring to cells in the spreadsheet itself are not being handled properly. This is the first namespacing regression identified for release 19. Usual cause and fix - need to take greater care with attributes than was previously the case.
oleibman
Adrien Crivelli
oleibman