Use guard for QT5/XCB also for cmake build.

See commit d4428ceb81d12dde60102ad0bb3d1503efc54eda
from Enrico Forestieri

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 43a0345c0e69a8b60a2ca6175703faa2b489308f..33daf5b699a493a2184a2fe5c812ba17b1a2dd38 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -588,7 +588,9 @@ if(LYX_XMINGW)
        list(APPEND CMAKE_FIND_ROOT_PATH ${GNUWIN32_DIR})
 endif()
 
+set(QPA_XCB)
 if(LYX_USE_QT MATCHES "QT5")
+       # set QPA_XCB if QT uses X11
        find_package(Qt5Core REQUIRED)
        if (Qt5Core_FOUND)
                find_package(Qt5Widgets REQUIRED)
@@ -596,6 +598,9 @@ if(LYX_USE_QT MATCHES "QT5")
                        find_package(Qt5MacExtras REQUIRED)
                endif()
                find_package(Qt5X11Extras QUIET)
+               if(Qt5X11Extras_FOUND)
+                 set(QPA_XCB 1)
+               endif()
                find_package(Qt5WinExtras QUIET)
                set(QTVERSION ${Qt5Core_VERSION})
                macro (qt_use_modules)