KOffice allows developers to create third party plugins which can be distributed and built separately from the main KOffice distribution.
To build a custom docker you must have both "cmake" (the build system used by KDE and KDE applications), and the include files for the KOffice libraries installed. The include files are usually installed alongside the KOffice development libraries, which are usually either packaged with KOffice or in a separate "koffice-devel" package.
Installing the docker plugin is actually very simple. Download and untar the plugin source code. Then change to the source code directory and type:
mkdir build && cd build
To create the appropriate makefile, you should now use cmake:
cmake -DCMAKE_INSTALL_DIR=/usr ..
Instead of /usr, you should use $KDEDIR, the root directory under which your local KDE installation has been placed. You can usually figure out what this directory is by typingkde4-config --prefix (or kde-config --prefix) at the command line.
Now you are ready to build the project.
Type make and hit enter.
When the build finishes, become root (or use sudo) to execute:
make install
If you fire up a KOffice application (such as KWord), you should now be able to go to select
to enable the new plugin.
Writing your own docker plugin is much easier than it sounds. There are good intructions at techbase.
KDE UserBase Wiki 