> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/ios/changelogs/version-5/v5-8-1-14225.md).

# Version 5.8.1.14225

Explore the latest updates in PDFTron SDK 6.3.0, including new properties and selectors for enhanced functionality. Improve your PDF viewing experience with pinch zooming, document locking, form field

Release Date: 2012.06.20

## Changes to PDFViewCtrl:

* New property zoomEnabled to enabled/disable pinch zooming.
* New selectors LockDoc:, TryLockDoc, UnlockDoc to help with locking the document.
* New selector SetZoomMinimum:Maximum:Mode: to limit the zoom.
* New selector SetHighlightFields: to highlight form fields.
* New selector SetPathHinting: to turn path hinting on and off.
* New selector SetContentBufferSize: to control how much memory PDFViewControl allocates to its display buffer.
* New selector OpenUrl:WithPassword to open a PDF from an HTTP server.
* Improved font substitution on for PDF's that don't embed fonts.
* Now possible to write custom filters.
* Bug fixes

## Change to PDFDoc:

* New selector HasXFA that checks for the presence of XFA (dynamic) forms.

## Changes to Tools:

* Numerous improvements in the overall behaviour of the tools
* Bug fixes


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