Initial UI hint that tells a viewer which side panel to show when the document opens (ISO 32000-1 §7.7.2 Table 28, /PageMode).
/PageMode
The "Use*" naming preserves the spec's PDF-name values verbatim.
No panel: page area only (default).
Show the bookmarks (outlines) panel.
Show the thumbnails panel.
Full-screen mode, no menu bar / window controls / panel.
Show the optional-content (layers) panel. Added in PDF 1.5.
Show the attachments panel. Added in PDF 1.6.
A /PageMode value we don't recognise.
Returns a representation of an immutable list of all enum entries, in the order they're declared.
Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
Returns an array containing the constants of this enum type, in the order they're declared.