shouldStartLoadWithRequest：不需要圖像

我有一個UIWebView，我使它加載一個HTML字符串。該字符串包含圖像的http url。圖像被加載，但不調用shouldStartLoadWithRequest:方法。它只被調用一次，對於about : blank。但是，所有圖像請求都成功傳遞到我的NSURLCache子類中，轉換爲cachedResponseForRequest:方法。但我想處理shouldStartLoadWithRequest:方法中的請求。可以做任何事情嗎？我怎樣才能讓這些請求進入委託方法？shouldStartLoadWithRequest：不需要圖像

下面是代碼：

@interface URLCache : NSURLCache 

@end 

@implementation URLCache 

- (NSCachedURLResponse *)cachedResponseForRequest:(NSURLRequest *)request 
{ 
    NSLog(@"REQUEST = %@", request.URL); 

    return [super cachedResponseForRequest:request]; 
} 

@end 

@interface ViewController()<UIWebViewDelegate> 

@end 

@implementation ViewController 

- (void)viewDidLoad { 
    [super viewDidLoad]; 

    [NSURLCache setSharedURLCache:[URLCache new]]; 

    NSString* path = [[NSBundle mainBundle] pathForResource:@"test" ofType:@"html"]; 
    NSString* html = [NSString stringWithContentsOfFile:path 
              encoding:NSUTF8StringEncoding 
               error:nil]; 

    self.webView.delegate = self; 

    [self.webView loadHTMLString:html baseURL:nil]; 
} 

- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType 
{ 
    NSLog(@"URL = %@", request.URL); 

    return YES; 
} 

@end

來源

2017-06-21 Andrey Chernukha