Examples: Downgrading projects to xcode 9.2 (maybe 8.0) (#2134)

* example_apple_opengl2: The deployment target was set to 10.12 from XCode 9.2.
* imgui_impl_metal: header not found by XCode 9.2.
* example_apple_metal: The deployment target was set to 10.12 from XCode 9.2.

examples/example_apple_metal/example_apple_metal.xcodeproj/project.pbxproj

@@ -231,14 +231,16 @@
 				TargetAttributes = {
 					8307E7C320E9F9C900473790 = {
 						CreatedOnToolsVersion = 9.4.1;
+						ProvisioningStyle = Automatic;
 					};
 					8307E7D920E9F9C900473790 = {
 						CreatedOnToolsVersion = 9.4.1;
+						ProvisioningStyle = Automatic;
 					};
 				};
 			};
 			buildConfigurationList = 8307E7B920E9F9C700473790 /* Build configuration list for PBXProject "example_apple_metal" */;
-			compatibilityVersion = "Xcode 9.3";
+			compatibilityVersion = "Xcode 8.0";
 			developmentRegion = en;
 			hasScannedForEncodings = 0;
 			knownRegions = (
@@ -444,10 +446,7 @@
 				DEVELOPMENT_TEAM = "";
 				INFOPLIST_FILE = "$(SRCROOT)/iOS/Info-iOS.plist";
 				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
-				LD_RUNPATH_SEARCH_PATHS = (
-					"$(inherited)",
-					"@executable_path/Frameworks",
-				);
+				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "org.imgui.example.apple-metal-ios";
 				PRODUCT_NAME = example_apple_metal;
 				SDKROOT = iphoneos;
@@ -463,10 +462,7 @@
 				DEVELOPMENT_TEAM = "";
 				INFOPLIST_FILE = "$(SRCROOT)/iOS/Info-iOS.plist";
 				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
-				LD_RUNPATH_SEARCH_PATHS = (
-					"$(inherited)",
-					"@executable_path/Frameworks",
-				);
+				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "org.imgui.example.apple-metal-ios";
 				PRODUCT_NAME = example_apple_metal;
 				SDKROOT = iphoneos;
@@ -483,11 +479,8 @@
 				COMBINE_HIDPI_IMAGES = YES;
 				DEVELOPMENT_TEAM = "";
 				INFOPLIST_FILE = "$(SRCROOT)/macOS/Info-macOS.plist";
-				LD_RUNPATH_SEARCH_PATHS = (
-					"$(inherited)",
-					"@executable_path/../Frameworks",
-				);
-				MACOSX_DEPLOYMENT_TARGET = 10.13;
+				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/../Frameworks";
+				MACOSX_DEPLOYMENT_TARGET = 10.12;
 				PRODUCT_BUNDLE_IDENTIFIER = "org.imgui.example.apple-metal-macos";
 				PRODUCT_NAME = example_apple_metal;
 				SDKROOT = macosx;
@@ -502,11 +495,8 @@
 				COMBINE_HIDPI_IMAGES = YES;
 				DEVELOPMENT_TEAM = "";
 				INFOPLIST_FILE = "$(SRCROOT)/macOS/Info-macOS.plist";
-				LD_RUNPATH_SEARCH_PATHS = (
-					"$(inherited)",
-					"@executable_path/../Frameworks",
-				);
-				MACOSX_DEPLOYMENT_TARGET = 10.13;
+				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/../Frameworks";
+				MACOSX_DEPLOYMENT_TARGET = 10.12;
 				PRODUCT_BUNDLE_IDENTIFIER = "org.imgui.example.apple-metal-macos";
 				PRODUCT_NAME = example_apple_metal;
 				SDKROOT = macosx;

examples/example_apple_opengl2/example_apple_opengl2.xcodeproj/project.pbxproj

@@ -135,11 +135,12 @@
 				TargetAttributes = {
 					4080A96A20B029B00036BA46 = {
 						CreatedOnToolsVersion = 9.3.1;
+						ProvisioningStyle = Automatic;
 					};
 				};
 			};
 			buildConfigurationList = 4080A96620B029B00036BA46 /* Build configuration list for PBXProject "example_apple_opengl2" */;
-			compatibilityVersion = "Xcode 9.3";
+			compatibilityVersion = "Xcode 8.0";
 			developmentRegion = en;
 			hasScannedForEncodings = 0;
 			knownRegions = (
@@ -286,6 +287,7 @@
 			isa = XCBuildConfiguration;
 			buildSettings = {
 				CODE_SIGN_STYLE = Automatic;
+				MACOSX_DEPLOYMENT_TARGET = 10.12;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SYSTEM_HEADER_SEARCH_PATHS = ../libs/gl3w;
 				USER_HEADER_SEARCH_PATHS = ../..;
@@ -296,6 +298,7 @@
 			isa = XCBuildConfiguration;
 			buildSettings = {
 				CODE_SIGN_STYLE = Automatic;
+				MACOSX_DEPLOYMENT_TARGET = 10.12;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SYSTEM_HEADER_SEARCH_PATHS = ../libs/gl3w;
 				USER_HEADER_SEARCH_PATHS = ../..;

examples/imgui_impl_metal.mm

@@ -17,7 +17,7 @@
 #include "imgui_impl_metal.h"
 
 #import <Metal/Metal.h>
-#import <QuartzCore/CAMetalLayer.h>
+// #import <QuartzCore/CAMetalLayer.h> // Not suported in XCode 9.2. Maybe a macro to detect the SDK version can be used (something like #if MACOS_SDK >= 10.13 ...)
 #import <simd/simd.h>
 
 #pragma mark - Support classes