Background-load symbol libraries and footprints

[Alessio Morale]

From EESchema when adding a new symbol "Choose symbol" forms takes a lot of time to show the first time.
Consider the possibility to preload symbols and footprints in background when the program starts, so that it may show up quickly.

[Nick Østergaard (nickoe)]

Please add version information.

I think this is dangerous, letting the user add symbols before they are loaded could probably lead to more problems that it solves.

[Wayne Stambaugh (stambaughw)]

@Nick, I think the submitter meant to load the contents of the library tables in the background possibly in a separate thread which has been discussed in the past. It's just a low priority.

[Alessio Morale (alessiomorale)]

Yes, as described by Wayne the idea is to spawn a task to asynchronously load library tables as soon as EESchema starts.
If a user tries to open the "Choose Symbol" window before they are loaded then a progress bar shall be shown and the user must wait until it is done.

Not sure whether it is still relevant, but below there is the version info:
Application: kicad
Version: (5.0.0), release build
Libraries:
    wxWidgets 3.0.3
    libcurl/7.54.1 OpenSSL/1.0.2l zlib/1.2.11 libssh2/1.8.0 nghttp2/1.23.1 librtmp/2.3
Platform: Windows 8 (build 9200), 64-bit edition, 64 bit, Little endian, wxMSW
Build Info:
    wxWidgets: 3.0.3 (wchar_t,wx containers,compatible with 2.8)
    Boost: 1.60.0
    OpenCASCADE Community Edition: 6.8.0
    Curl: 7.54.1
    Compiler: GCC 7.1.0 with C++ ABI 1011

Build settings:
    USE_WX_GRAPHICS_CONTEXT=OFF
    USE_WX_OVERLAY=OFF
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_ACTION_MENU=OFF
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON

[Fabián Inostroza (fabianinostroza)]

Maybe a cache of the information kicad is generating would also work. In my machine it takes aprox 30s to load the footprint editor for the first time.

[KiCad Janitor (kicad-janitor)]

KiCad bug tracker has moved to Gitlab. This report is now available here: https://gitlab.com/kicad/code/kicad/-/issues/2192