Add some comments about the meaning of versions

refs lxqt/lxqt/issues/1236

CMakeLists.txt

@@ -6,8 +6,19 @@ set(QT_MINIMUM_VERSION "5.5.0")
 set(QTXDG_MINIMUM_VERSION "2.0.0")
 set(LXQTBT_MINIMUM_VERSION "0.3.1")
 
+# Major LXQt Version, belong to all components
 set(LXQT_MAJOR_VERSION 0)
+# Minor LXQt Version, belong to all components
 set(LXQT_MINOR_VERSION 11)
+#
+# Patch Version, belong *only* to the component
+# LXQt is 0.11 - liblxqt is at patch version 1
+# The official LXQt version will follow liblxqt.
+#
+# In a perfect world all components would have the same major- and minor- and
+# patch-version as liblxqt - in real life it will be fine if every component
+# has it's own patch version within a major/minor life cyle.
+#
 set(LXQT_PATCH_VERSION 1)
 set(LXQT_VERSION ${LXQT_MAJOR_VERSION}.${LXQT_MINOR_VERSION}.${LXQT_PATCH_VERSION})
 

cmake/lxqt-config.cmake.in

@@ -17,6 +17,18 @@ find_dependency(KF5WindowSystem)
 find_dependency(lxqt-build-tools @LXQTBT_MINIMUM_VERSION@)
 include(LXQtConfigVars)
 
+
+#  - Set version informations
+set(LXQT_MAJOR_VERSION      "@LXQT_MAJOR_VERSION@")
+set(LXQT_MINOR_VERSION      "@LXQT_MINOR_VERSION@")
+set(LXQT_PATCH_VERSION      "@LXQT_PATCH_VERSION@")
+set(LXQT_VERSION            "@LXQT_VERSION@")
+
+add_definitions("-DLXQT_MAJOR_VERSION=\"${LXQT_MAJOR_VERSION}\"")
+add_definitions("-DLXQT_MINOR_VERSION=\"${LXQT_MINOR_VERSION}\"")
+add_definitions("-DLXQT_PATCH_VERSION=\"${LXQT_PATCH_VERSION}\"")
+add_definitions("-DLXQT_VERSION=\"${LXQT_VERSION}\"")
+
 if (NOT TARGET @LXQT_LIBRARY_NAME@)
     if (POLICY CMP0024)
         cmake_policy(SET CMP0024 NEW)