kimgio generator: Make kexiv2 dependency optional

getting keviv2 to build on Android is hard (TM)

generators/CMakeLists.txt

@@ -109,9 +109,7 @@ if(LIBSPECTRE_FOUND)
   add_subdirectory(spectre)
 endif(LIBSPECTRE_FOUND)
 
-if(KF5KExiv2_FOUND)
-  add_subdirectory( kimgio )
-endif()
+add_subdirectory( kimgio )
 
 if(CHM_FOUND AND KF5KHtml_FOUND AND LIBZIP_FOUND)
   add_subdirectory( chm )

generators/kimgio/CMakeLists.txt

@@ -4,9 +4,14 @@ add_definitions(-DTRANSLATION_DOMAIN="okular_kimgio")
 ########### next target ###############
 
 okular_add_generator(okularGenerator_kimgio generator_kimgio.cpp)
-target_link_libraries(okularGenerator_kimgio okularcore KF5::KExiv2 KF5::I18n)
+target_link_libraries(okularGenerator_kimgio okularcore KF5::I18n)
 
-if(BUILD_TESTING AND BUILD_DESKTOP)
+if(KF5KExiv2_FOUND)
+    target_compile_definitions(okularGenerator_kimgio PRIVATE -DWITH_KEXIV=1)
+    target_link_libraries(okularGenerator_kimgio KF5::KExiv2)
+endif()
+
+if(BUILD_TESTING AND BUILD_DESKTOP AND KF5KExiv2_FOUND)
     add_definitions( -DKDESRCDIR="${CMAKE_CURRENT_SOURCE_DIR}/" )
     set( kimgiotest_SRCS tests/kimgiotest.cpp ${CMAKE_SOURCE_DIR}/part/pagepainter.cpp ${CMAKE_SOURCE_DIR}/part/guiutils.cpp ${CMAKE_SOURCE_DIR}/part/debug_ui.cpp )
     ecm_add_test(${kimgiotest_SRCS} TEST_NAME "kimgiotest" LINK_LIBRARIES okularcore okularpart Qt5::Svg Qt5::Test)

generators/kimgio/generator_kimgio.cpp

@@ -25,7 +25,9 @@
 #include <QAction>
 #include <QIcon>
 
+#ifdef WITH_KEXIV
 #include <kexiv2/kexiv2.h>
+#endif
 
 #include <core/page.h>
 
@@ -81,11 +83,13 @@ bool KIMGIOGenerator::loadDocumentInternal(const QByteArray &fileData, const QSt
     auto mime = db.mimeTypeForFileNameAndData(fileName, fileData);
     docInfo.set(Okular::DocumentInfo::MimeType, mime.name());
 
+#ifdef WITH_KEXIV
     // Apply transformations dictated by Exif metadata
     KExiv2Iface::KExiv2 exifMetadata;
     if (exifMetadata.loadFromData(fileData)) {
         exifMetadata.rotateExifQImage(m_img, exifMetadata.getImageOrientation());
     }
+#endif
 
     pagesVector.resize(1);