Files
PhpSpreadsheet/samples/templates/32readwriteLineChart6.xlsx
oleibman 0e6866d6f0 Font/Effects/Theme Support for Chart Data Labels and Axis (#3476)
* Font and Effects Support for Chart Data Labels and Axis

Addresses some remaining issues with 32readwriteLineChart5 (see issue #1797). Font size is covered. So are effects, although the results are a bit odd. For the new spreadsheet 32readwriteLineChart6, the Axis labels have a yellow-ish glow, but reading and writing the spreadsheet in PhpSpreadsheet gives them a purple-ish glow. Nevertheless, the new test shows that the output file uses schemeClr accent4, as does the input file. So the effect is handled correctly, but it seems there is likely to be a difference between theme colors (Writer/Xlsx/Theme appears to write hard-coded color schemes, and, in any case, Reader/Xlsx does not appear to handle schemeClr). Fixing that will be a great deal more difficult, with a large chance of regression, and will need to happen in a separate PR (one that I am not currently investigating, but I will open a new issue). Effects using srgbClr (and probably sysclr) should be okay.

* Better Theme Support

When reading Xlsx, the theme colors will now also be used for writing. This means that a file can be loaded and saved and its chart colors will now be preserved. If the spreadsheet is created new, Excel 2007-2010 colors are used. The writer is currently hard-coded to use them, so this avoids making this a breaking change. The theme colors can be explicitly changed if desired, and Excel 2013+ colors can be introduced very easily.
```php
$spreadsheet->getTheme()
    ->setThemeColorName(Theme::COLOR_SCHEME_2013_PLUS_NAME);
```
Likewise, if the old behavior of changing to the 2007-2010 scheme rather than using the input values is desired, that is easy to achieve after the load has taken place.
```php
$spreadsheet->getTheme()
    ->setThemeColorName(Theme::COLOR_SCHEME_2007_2010_NAME);
```
The new Theme class introduced by this change can easily be extended to include Fonts and Effects. Unlike Colors, I am unsure what the practical effects of changing those to, say, the 2013+ defaults would be.

* Scrutinizer

Use an alias in a use statement.

* Update Change Log

Due to potential behavior change.
2023-03-26 03:19:34 -07:00

13 KiB