Hello everyone, I have an integration in Libre Office in C++ that creates a custom toolbar, created following the example from the official Libre Office Github. I needed to change the icons as the application loaded, I tried many different methods, but in the end I came to the editing configuration method (.xcu), my method for editing icons in the configuration looks like this:
void BaseDispatch::ChangeIcon(OUString addinPath, OUString oldIconName, OUString newIconName) {
auto access = configuration::ReadWriteAccess::create(mxContext, OUString("*"));
Any userDefImgAny;
userDefImgAny = access->getByHierarchicalName(
OUString("/org.openoffice.Office.Addons/AddonUI/Images/['vnd.demo.complextoolbarcontrols.") + oldIconName + "']/UserDefinedImages");
Reference<XInterface> userDefImg = *(XInterface**)userDefImgAny.getValue();
Reference<XPropertySet> userDefImgProperties(userDefImg, UNO_QUERY);
userDefImgProperties->setPropertyValue("ImageSmallURL", Any(addinPath + OUString("/Icons/16x16/") + newIconName + OUString(".png")));
userDefImgProperties->setPropertyValue("ImageBigURL", Any(addinPath + OUString("/Icons/26x26/") + newIconName + OUString(".png")));
access->commitChanges();
}
this method is called when creating the BaseDispatch class (analogous to the class from [https://github.com/LibreOffice/core/blob/master/odk/examples/cpp/complextoolbarcontrols/MyProtocolHandler.h](complextoolbarcontrols sample))
however, when you open LibreOffice for the first time, text appears in place of the new icons. I checked with a debugger all the paths to the icons and the feasibility of the functions - everything is correct. I checked if the main configuration file (registrymodifications.xcu) is being changed - the paths to the new icons are there, and I feel that the changes are simply not being applied. I spent a lot of time looking for a solution, please help me! 
P.S. when you open Libre Office for the second time, new icons are displayed correctly.