Follow App Store submit rule, upgrade the min Xcode version to Xcode 9.0

Using `@available` and `API_AVAILABLE` to check API availability

Examples/SDWebImage Demo/LaunchScreen.storyboard

@@ -1,8 +1,12 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="10117" systemVersion="16C67" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" useTraitCollections="YES" initialViewController="01J-lp-oVM">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="14113" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" useTraitCollections="YES" colorMatched="YES" initialViewController="01J-lp-oVM">
+    <device id="retina4_7" orientation="portrait">
+        <adaptation id="fullscreen"/>
+    </device>
     <dependencies>
         <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="10085"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="14088"/>
+        <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
     <scenes>
         <!--View Controller-->
@@ -14,9 +18,9 @@
                         <viewControllerLayoutGuide type="bottom" id="xb3-aO-Qok"/>
                     </layoutGuides>
                     <view key="view" contentMode="scaleToFill" id="Ze5-6b-2t3">
-                        <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                        <rect key="frame" x="0.0" y="0.0" width="375" height="667"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
-                        <color key="backgroundColor" white="1" alpha="1" colorSpace="custom" customColorSpace="calibratedWhite"/>
+                        <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                     </view>
                 </viewController>
                 <placeholder placeholderIdentifier="IBFirstResponder" id="iYj-Kq-Ea1" userLabel="First Responder" sceneMemberID="firstResponder"/>

README.md

@@ -37,7 +37,7 @@ This library provides an async image downloader with cache support. For convenie
 - tvOS 9.0 or later
 - watchOS 2.0 or later
 - macOS 10.10 or later
-- Xcode 7.3 or later
+- Xcode 9.0 or later
 
 #### Backwards compatibility
 

SDWebImage/SDImageCoderHelper.m

@@ -203,20 +203,15 @@ static const CGFloat kDestSeemOverlap = 2.0f;   // the numbers of pixels to over
     static CGColorSpaceRef colorSpace;
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wunguarded-availability"
-        BOOL shouldUseSRGB = NO;
 #if SD_UIKIT
-        NSProcessInfo *processInfo = [NSProcessInfo processInfo];
-        shouldUseSRGB = processInfo.operatingSystemVersion.majorVersion >= 9;
-#endif
-        if (shouldUseSRGB) {
-            // This is what iOS/tvOS device used colorspace, combined with right bitmapInfo, even without decode, can still avoid extra CA::Render::copy_image(which marked `Color Copied Images` from Instruments)
+        if (@available(iOS 9.0, tvOS 9.0, *)) {
             colorSpace = CGColorSpaceCreateWithName(kCGColorSpaceSRGB);
         } else {
             colorSpace = CGColorSpaceCreateDeviceRGB();
         }
-#pragma clang diagnostic pop
+#else
+        colorSpace = CGColorSpaceCreateDeviceRGB();
+#endif
     });
     return colorSpace;
 }

SDWebImage/SDImageIOCoder.m

@@ -240,28 +240,15 @@
     static BOOL canDecode = NO;
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wunguarded-availability"
 #if TARGET_OS_SIMULATOR || SD_WATCH
         canDecode = NO;
-#elif SD_MAC
-        NSProcessInfo *processInfo = [NSProcessInfo processInfo];
-        if ([processInfo respondsToSelector:@selector(operatingSystemVersion)]) {
-            // macOS 10.13+
-            canDecode = processInfo.operatingSystemVersion.minorVersion >= 13;
-        } else {
-            canDecode = NO;
-        }
-#elif SD_UIKIT
-        NSProcessInfo *processInfo = [NSProcessInfo processInfo];
-        if ([processInfo respondsToSelector:@selector(operatingSystemVersion)]) {
-            // iOS 11+ && tvOS 11+
-            canDecode = processInfo.operatingSystemVersion.majorVersion >= 11;
+#else
+        if (@available(iOS 11.0, tvOS 11.0, macOS 10.13, *)) {
+            canDecode = YES;
         } else {
             canDecode = NO;
         }
 #endif
-#pragma clang diagnostic pop
     });
     return canDecode;
 }

SDWebImage/SDWebImageCompat.h

@@ -63,10 +63,6 @@
         #define UIColor NSColor
     #endif
 #else
-    #if __IPHONE_OS_VERSION_MIN_REQUIRED != 20000 && __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_5_0
-        #error SDWebImage doesn't support Deployment Target version < 5.0
-    #endif
-
     #if SD_UIKIT
         #import <UIKit/UIKit.h>
     #endif

SDWebImage/SDWebImageTransition.h

@@ -41,7 +41,7 @@ typedef void (^SDWebImageTransitionCompletionBlock)(BOOL finished);
 /**
  The timing function used for all animations within this transition animation (macOS).
  */
-@property (nonatomic, strong, nullable) CAMediaTimingFunction *timingFunction NS_AVAILABLE_MAC(10_7);
+@property (nonatomic, strong, nullable) CAMediaTimingFunction *timingFunction API_UNAVAILABLE(ios, tvos, watchos);
 /**
  A mask of options indicating how you want to perform the animations.
  */