* Performance Improvement for Xlsx Reader
Fix#3683. PR #3497 fixed a problem involving formulas and the quotePrefix style attribute. It did so by automatically turning off quotePrefix for any formulas encountered by Xlsx Reader. Under the right circumstances, it turns out that that change can cause a file read to take noticeably more time than previously. This change will turn off quotePrefix only if it is already on, and that appears to eliminate the performance problem while continuing to solve the original problem.
* Very Minor Improvement
* Update CHANGELOG.md
* Xlsx Support Flipping of Image
Fix#731. Opened over 5 years ago, probably the second oldest problem I've worked on. Images attached to an Xlsx spreadsheet can be rotated, which is supported by PhpSpreadsheet. They can also be flipped along their horizontal and/or vertical axes, and that has not been supported. This PR adds that support.
* Update CHANGELOG.md
* Sheet Background Images
Fix#1649, a 3-year-old issue long marked "stale". Excel supports background images on sheets; now PhpSpreadsheet will as well. Support is limited to Xlsx (read and write) and Html (write only). As far as I can tell, Excel Xml and Gnumeric do not support this, nor, of course, do Csv and Slk; Excel Xls does, but, as usual, how to handle it in BIFF format is a mystery; LibreOffice ODS supports it differently than Excel, and this is just another of many ODS style properties not currently supported by PhpSpreadsheet.
* Update CHANGELOG.md
* Two Problems with Html Chart Rendering - Minor Break
Several problems are noted in #3783. This PR addresses those problems which make the rendering unsatisfactory (see following paragraphs). It does not address some items where the rendering is IMO satisfactory although it doesn't match Excel. In particular, the use of a different color palette and the rotation of charts are not addressed. I will leave the issue open for now because of those.
As for the items which are addressed, in some cases the Html was omitting a chart altogether. This is because it had been extending the column range for charts only when it decided that extending the row range was needed. The code is changed to now extend the column range whenever the chart begins beyond the current column range of the sheet.
Also, the rendering always produced a fixed-size image, so saving as Html could result in charts overlaying each other or other parts of the spreadsheet. New properties `renderedWidth` and `renderedHeight` are added to Chart, along with setters and getters. Writer/Html is changed to set these values using the chart's top left and bottom right cells to try to determine the actual size that is needed. Users can also set these properties outside of Writer/Html if they wish. Thanks to @f1mishutka for determining the source of this problem and suggesting an approach to resolving it.
Because the size of the rendered image in Html/Pdf is changed, this could be considered a breaking change. To restore the prior behavior, do the following for all charts before saving as Html:
```php
$chart->setRenderedWidth(640.0);
$chart->setRenderedHeight(480.0);
```
* Update CHANGELOG.md
* Slk Shared Formulas
Fix#2267. The Slk format has a way to express a "shared formula", but the Slk reader does not yet understand it. Thanks to @SheetJSDev for documenting the problem and pointing the way towards a solution. It has taken a long time to get there. Part of the problem is that I have not been successful in getting Excel to use this type of construction when saving a Slk file. So I have resorted to saving a Slk file where shared formulas *could* be used, and then editing it by hand to actually use them. It would not surprise me in the least to have neglected one or more possible ways to specify a shared formula; but, at least the issue as documented is resolved, and if new issues arise, we'll probably be in better shape to deal with them.
* Update CHANGELOG.md
* Theme File Missing But Referenced in Spreadsheet
Fix#3770. A rels file points to a non-existent theme file in the spreadsheet. In other similar cases (e.g. PR #3771), Excel opens such a spreadsheet, but with an error pop-up. Not so with this file; it just opens the spreadsheet without the pop-up. PhpSpreadsheet will now account for this unusual situation as well.
* Update CHANGELOG.md
* Allow Users to Support Additional Tags in Helper/Html
Fix#3751. User wants to add bullets for list items, and possibly handle table rows and other currently unsupported tags where one size might not fit all.
* Update CHANGELOG.md
This is according to our formal, published, policy to only support
EOL PHP after 6 months.
See https://phpspreadsheet.readthedocs.io/en/latest/#php-version-support
Also share the exact same dev deps across all PHP version for GitHub
Actions so runs are faster, much most importantly they are stable and
predictable. And we decide manually when we want to migrate to PHPUnit
10.
Fixes#3634Closes#3710
* Use Column Style When Row Dimension Exists Without Style
Fix#3534. For new cells, style is set to Row Dimension Style when Row Dimension exists (even if Row Dimension Style does not exist), else Column Dimension Style when Column Dimension exists. However it should be set to Row Dimension Style when Row Dimension exists *and* Row Dimension Style exists, else ...
* Address Issue 3533
If cell is defined in xml, it uses neither row nor column style. If style is omitted in cell definition, default style is used.
* Update CHANGELOG.md
* 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.