This way it works out of the box.

CMakeLists.txt

@@ -70,6 +70,43 @@ add_executable(flattests ${FlatBuffers_Tests_SRCS})
 add_executable(flatsamplebinary ${FlatBuffers_Sample_Binary_SRCS})
 add_executable(flatsampletext ${FlatBuffers_Sample_Text_SRCS})
 
+#----------------------------------------------------------------------------
+# Copy all example files to the build directory. Important for 
+# out of place builds. The progem flatsampletext requires that monster.fbs
+# and monsterdata.json be in the directory ./samples
+#
+set(NEEDED_FILES
+   monster.fbs
+   monsterdata.json
+)
+
+foreach(NEEDED_ ${NEEDED_FILES})
+  configure_file(
+    ${PROJECT_SOURCE_DIR}/samples/${NEEDED_}
+    ${PROJECT_BINARY_DIR}/samples/${NEEDED_}
+    COPYONLY
+    )
+endforeach()
+
+#----------------------------------------------------------------------------
+# Copy all example files to the build directory. Important for 
+# out of place builds. The progem flattests requires that monster_test.fbs
+# and monsterdata_test.json be in the directory ./test
+#
+set(NEEDED_FILES
+   monster_test.fbs
+   monsterdata_test.json
+)
+
+foreach(NEEDED_ ${NEEDED_FILES})
+  configure_file(
+    ${PROJECT_SOURCE_DIR}/tests/${NEEDED_}
+    ${PROJECT_BINARY_DIR}/tests/${NEEDED_}
+    COPYONLY
+    )
+endforeach()
+
+#----------------------------------------------------------------------------
 add_test(NAME flattest
          CONFIGURATIONS Debug
          WORKING_DIRECTORY tests

build/Xcode/FlatBuffers.xcodeproj/project.pbxproj

@@ -338,6 +338,7 @@
 		02575EDE5A1349C9A3584E32 /* RelWithDebInfo */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				CONFIGURATION_BUILD_DIR = .;
 				ONLY_ACTIVE_ARCH = YES;
 				SDKROOT = /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk;
 				SYMROOT = build;
@@ -758,6 +759,7 @@
 		60917B4900A4484898ED29EF /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				CONFIGURATION_BUILD_DIR = .;
 				ONLY_ACTIVE_ARCH = YES;
 				SDKROOT = /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk;
 				SYMROOT = build;
@@ -767,6 +769,7 @@
 		65B8F01CB7E6407CB262E6B6 /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				CONFIGURATION_BUILD_DIR = .;
 				ONLY_ACTIVE_ARCH = YES;
 				SDKROOT = /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk;
 				SYMROOT = build;
@@ -926,6 +929,7 @@
 		C839EDC9489F432994623A13 /* MinSizeRel */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				CONFIGURATION_BUILD_DIR = .;
 				ONLY_ACTIVE_ARCH = YES;
 				SDKROOT = /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk;
 				SYMROOT = build;