edouard@3925: Pages, Jumps and HMI_NODE relativity
edouard@3925: ====================================
edouard@3925: 
edouard@3925: Pages are full screen. Only one page is displayed at the same time.
edouard@3925: 
edouard@3925: Page change is triggered by ``HMI:Jump`` and ``HMI:Back``, or by changing ``/CURRENTPAGE_N``.
edouard@3925: 
edouard@3925: .. code-block:: text
edouard@3925: 
edouard@3925:     HMI:Page:PageName[@RootPath]
edouard@3925:     HMI:Jump:PageName[@RelativePath]
edouard@3925:     HMI:Back
edouard@3925: 
edouard@3925: Absolute and relative pages
edouard@3925: ---------------------------
edouard@3925: 
edouard@3925: When ``[@RootPath]`` is given, page is relative.
edouard@3925: 
edouard@3925: When using ``HMI:Jump`` to reach a relative page, a compatible
edouard@3925: ``[@RelativePath]`` may be provided.
edouard@3925: 
edouard@3925: To be compatible, ``RootPath`` and ``RelativePath`` must both point to
edouard@3925: HMI tree nodes of type ``HMI_NODE`` instanciated from same POU.
edouard@3925: 
edouard@3925: Every widget using a path descendant of ``RootPath`` in a relative
edouard@3925: page is relative. Relative widgets get the ``RootPath`` section of
edouard@3925: their path replaced by ``RelativePath``.
edouard@3925: 
edouard@3925: Relative page label::
edouard@3925: 
edouard@3925:     HMI:Page:PageName
edouard@3925: 
edouard@3925: Absolute page label::
edouard@3925: 
edouard@3925:     HMI:Page:PageName@RootPath
edouard@3925: 
edouard@3936: Example::
edouard@3936: 
edouard@3936:     HMI:Page:PumpControl@/PUMP0
edouard@3936: 
edouard@3925: .. image:: svghmi_relative.svg
edouard@3925: 
edouard@3925: 
edouard@3936: Jumps
edouard@3936: -----
edouard@3925: 
edouard@3925: 
edouard@3925: ``HMI:Jump`` can have ``inactive``, ``active`` and ``disabled`` labeled children:
edouard@3925: 
edouard@3925:     * ``inactive`` is shown when target page is not currently displayed
edouard@3925:     * ``active`` is shown when target page is currently displayed
edouard@3925:     * ``disabled`` is shown when relative page's RootPath is set to 0, disabling jump.
edouard@3925: 
edouard@3925: Relative page label::
edouard@3925: 
edouard@3936:     HMI:Jump:PageName@RelativePath
edouard@3925: 
edouard@3925: Absolute page label::
edouard@3925: 
edouard@3925:     HMI:Jump:PageName
edouard@3925: 
edouard@3936: Example::
edouard@3925: 
edouard@3936:     HMI:Jump:PumpControl@/PUMP7
edouard@3925: 
edouard@3925: 
edouard@3936: Back: Jump to previous page
edouard@3936: ----------------------------
edouard@3936: 
edouard@3936: ``HMI:Back`` takes no parameter and goes back one step in page change history when clicked.
edouard@3936: 
edouard@3936: 
edouard@3936: Special ``/CURRENT_PAGE_n`` variable
edouard@3925: -----------------------------------
edouard@3925: 
edouard@3936: Each SVGHMI instance have its own ``/CURRENT_PAGE_n``, with ``n`` being the position of SVGHMI instance in Configuration Tree.
edouard@3936: 
edouard@3936: By reading ``/CURRENT_PAGE_n`` value, PLC knows last page being displayed in HMI. Variable is of type STRING, and formatted as follows::
edouard@3936: 
edouard@3936:     PageName
edouard@3936: 
edouard@3936: 
edouard@3936: 
edouard@3925: ..
edouard@3925:     TODO
edouard@3925: 
edouard@3925: 
edouard@3925: Overlapping geometry
edouard@3925: --------------------
edouard@3925: 
edouard@3925: If widget's bounding box is included in page bounding box, then widget is part of page.
edouard@3925: 
edouard@3925: ..
edouard@3925:     TODO
edouard@3925: 
edouard@3936: Discarded element
edouard@3936: -----------------
edouard@3936: 
edouard@3925: 
edouard@3925: References frames
edouard@3925: -----------------
edouard@3925: 
edouard@3925: References frames help to unclutter page and widgets.
edouard@3925: 
edouard@3925: ..
edouard@3925:     TODO
edouard@3925: 
edouard@3925: Screensaver
edouard@3925: -----------
edouard@3925: 
edouard@3925: ..
edouard@3925:     TODO
edouard@3925: 
edouard@3925: Fading
edouard@3925: ------
edouard@3925: 
edouard@3925: ..
edouard@3925:     TODO
edouard@3929: 
edouard@3929: Go full screen
edouard@3929: --------------
edouard@3929: 
edouard@3929: ..
edouard@3929:     TODO