添加图片库、封装

keyBoard/Class/Categories/KBWebImageManager.m

@@ -0,0 +1,51 @@
+//
+//  KBWebImageManager.m
+//  keyBoard
+//
+
+#import "KBWebImageManager.h"
+#import <SDWebImage/SDWebImage.h>
+
+static inline NSURL *_KBURL(id url) {
+    if (!url) return nil;
+    if ([url isKindOfClass:NSURL.class]) return url;
+    if ([url isKindOfClass:NSString.class]) return [NSURL URLWithString:(NSString *)url];
+    return nil;
+}
+
+@implementation KBWebImageManager
+
++ (void)prefetchURLs:(NSArray<id> *)urlList
+            progress:(void(^)(NSUInteger finished, NSUInteger total))progress
+           completed:(void(^)(NSUInteger finished, NSUInteger skipped))completed {
+    NSMutableArray<NSURL *> *urls = [NSMutableArray arrayWithCapacity:urlList.count];
+    for (id u in urlList) { NSURL *nu = _KBURL(u); if (nu) [urls addObject:nu]; }
+    [[SDWebImagePrefetcher sharedImagePrefetcher] prefetchURLs:urls progress:^(NSUInteger noOfFinishedUrls, NSUInteger noOfTotalUrls) {
+        if (progress) progress(noOfFinishedUrls, noOfTotalUrls);
+    } completed:^(NSUInteger finishedCount, NSUInteger skippedCount) {
+        if (completed) completed(finishedCount, skippedCount);
+    }];
+}
+
++ (void)calculateDiskSize:(void(^)(NSUInteger bytes))completion {
+    [[SDImageCache sharedImageCache] calculateSizeWithCompletionBlock:^(NSUInteger fileCount, NSUInteger totalSize) {
+        if (completion) completion(totalSize);
+    }];
+}
+
++ (void)clearAllCache:(void(^)(void))completion {
+    SDImageCache *cache = SDImageCache.sharedImageCache;
+    [cache clearMemory];
+    [cache clearDiskOnCompletion:^{ if (completion) completion(); }];
+}
+
++ (void)setHTTPHeaderValue:(NSString *)value forKey:(NSString *)field {
+    if (value.length == 0) {
+        [[SDWebImageDownloader sharedDownloader] setValue:nil forHTTPHeaderField:field];
+    } else {
+        [[SDWebImageDownloader sharedDownloader] setValue:value forHTTPHeaderField:field];
+    }
+}
+
+@end
+