1163713bca
The previous command was not working, because of the lack of absolute path and also the wrong path to the test document. This should be fixed now. Change-Id: I2230041e17e4b6b33cfd44e5f15a5fce086a5f1c Reviewed-on: https://gerrit.libreoffice.org/c/core/+/176764 Tested-by: Jenkins Reviewed-by: Hossein <hossein@libreoffice.org> |
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qa | ||
source/gtk | ||
CppunitTest_libreofficekit_checkapi.mk | ||
CppunitTest_libreofficekit_tiledrendering.mk | ||
Executable_gtktiledviewer.mk | ||
Executable_tilebench.mk | ||
IwyuFilter_libreofficekit.yaml | ||
Library_libreofficekitgtk.mk | ||
Makefile | ||
Module_libreofficekit.mk | ||
Package_selectionhandles.mk | ||
README.md | ||
UIConfig_libreofficekit.mk | ||
UnoCommands.txt |
LibreOfficeKit
LibreOfficeKit can be used for accessing LibreOffice functionality through C/C++, without any need to use UNO.
For now it only offers document conversion (in addition to an experimental tiled rendering API).
Integrating LOK Into Other Software
LOK functionality can be accessed by including LibreOfficeKit.h[xx]
in your
program.
LOK initialisation (lok_init
) requires the inclusion of LibreOfficeKitInit.h
in
your program. If you use the C++ LibreOfficeKit.hxx
header, it already includes
LibreOfficeKitInit.h
for you.
(LibreOfficeKit.hxx
is a simple and fully inlined C++ wrapper for the same
functionality as in LibreOfficeKit.h
.)
An example program can be seen on: https://gitlab.com/ojwb/lloconv
Tiled Rendering
To use LOK Tiled Rendering you will need the following before the LOK includes:
#define LOK_USE_UNSTABLE_API
(This must be define before ANY LOK header, i.e. including the Init header.)
Currently only bitmap-buffer rendering is supported, with a 32-bit BGRA colorspace (further alternatives could feasibly be implemented as needed). Scanlines are ordered top-down (whereas LibreOffice will internally default to bottom-up).
Tiled Editing
On top of the tiled rendering API, a set of new methods have been added to the
lok::Document
class to allow basic editing, too. Communication between the LOK
client and LibreOffice is a two-way channel. The client can initiate an action
by calling the above mentioned methods. The most important methods for the
client -> LibreOffice communication are:
initializeForRendering()
, expected to be called right afterlok::Office::documentLoad()
returned alok::Document*
.postKeyEvent()
, expected to be called when the user provides input on the (soft-)keyboard.postMouseEvent()
, expected to be called when the user generated a touch or mouse event.
In general, all coordinates are always in absolute twips (20th of a point, or:
1" = 1440 twips). See lok::Document
in LibreOfficeKit.hxx
for a full list of
methods and their documentation.
The other way around (LibreOffice -> LOK client) is implemented using a
callback. A LOK client can register a callback using the registerCallback()
method. Whenever editing requires some action on the client side, a callback
event is emitted. The callback types are described using the
LibreOfficeKitCallbackType
enumeration in LibreOfficeKitEnums.h
, the callback
function signature itself is provided by the LibreOfficeKitCallback typedef in
LibreOfficeKitTypes.h
. The most important callback types:
LOK_CALLBACK_INVALIDATE_TILES
: drop all tiles cached on client-side that intersect with the provided rectangleLOK_CALLBACK_INVALIDATE_VISIBLE_CURSOR
: need to set the position and/or the size of the cursorLOK_CALLBACK_TEXT_SELECTION
: need to adjust the selection overlay provided by the client as the set of rectangles describing the selection overlay changed
There are currently two known LOK clients supporting tiled editing:
gtktiledviewer
(see below), which allows testing the LOK core implementation on (desktop) Linux- (LibreOffice on) Android
Core has next to no idea what is the LOK client, so for effective development,
it's recommended that the core part is developed against gtktiledviewer
, and
once a feature works there, then implement the Android part, with its slower
development iteration (slow uploading to the device, the need to link all
object files into a single .so
, etc).
LOK API guidelines
Introducing explicit new API under include/LibreOfficeKit/
adds type safety but listing each &
every micro-feature in those headers don't scale. Before extending those headers, consider using one
of the following alternatives, which require no changes to these headers:
- LOK client → core direction: use
postUnoCommand()
to dispatch an UNO command, optionally with parameters. - core → LOK client direction:
- Use
getCommandValues()
when this is initiated by the LOK client. - Use
LOK_CALLBACK_STATE_CHANGED
with a JSON payload when this is initiated by core.
- Use
It's useful to stick to these if possible, only add new C++ API when these are not a good fit.
- Debugging with gdb and
gtktiledviewer
To run gtktiledviewer
:
bin/run gtktiledviewer --lo-path=$PWD/instdir/program path/to/test.odt
To receive all incoming events from core use G_MESSAGES_DEBUG=all
G_MESSAGES_DEBUG=all bin/run gtktiledviewer --lo-path=$PWD/instdir/program ../test.odt
To debug with gdb
:
export LO_TRACE='gdb --tui --args'
before bin/run
, this will run gtktiledviewer in the debugger instead.
Building and running gtktiledviewer on Windows
A pre-requisite is pre-built GTK3 libraries. See official GTK documentation. Building of gtktiledviewer on Windows is enabled by passing
--with-gtk3-build=<path/to/GTK3/build/directory>
to configure.
Running the compiled executable requires GTK's bin in PATH:
PATH=${PATH}:/cygdrive/c/gtk-build/gtk/x64/release/bin bin/run gtktiledviewer --lo-path=$(cygpath -am $PWD/instdir/program) ../test.odt
LibreOfficeKitGtk
Currently consists of only a very basic GTK document viewer widget.
The widget uses g_info()
instead of SAL_INFO()
, use the G_MESSAGES_DEBUG=all
environment variable to display those messages.