ios/web/webui/crw_web_ui_page_builder.h

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef IOS_WEB_WEBUI_CRW_WEB_UI_PAGE_BUILDER_H_
   6 #define IOS_WEB_WEBUI_CRW_WEB_UI_PAGE_BUILDER_H_
   7
   8 #import <Foundation/Foundation.h>
   9
  10 #include "url/gurl.h"
  11
  12 namespace web {
  13 // Block type for WebUI page build completion callback.
  14 typedef void (^WebUIPageCompletion)(NSString*);
  15 // Block type for WebUI page builder delegate completion callback.
  16 typedef void (^WebUIDelegateCompletion)(NSString*, const GURL&);
  17 }  // namespace web
  18
  19 @class CRWWebUIPageBuilder;
  20
  21 // Delegate for CRWWebUIPageBuilder. Handles resource retrieval.
  22 @protocol CRWWebUIPageBuilderDelegate<NSObject>
  23 // Fetches resource for resourceURL and invokes completionHandler with the
  24 // result.
  25 - (void)webUIPageBuilder:(CRWWebUIPageBuilder*)webUIPageBuilder
  26     fetchResourceWithURL:(const GURL&)resourceURL
  27        completionHandler:(web::WebUIDelegateCompletion)completionHandler;
  28 @end
  29
  30 // Class for requesting and building WebUI HTML pages. Due to limitations on
  31 // custom network protocols for WKWebView, it is not possible to directly load
  32 // WebUI in WKWebView via the network stack. Instead, WebUI resources are
  33 // manually fetched from the network stack and then flattened and loaded into
  34 // the web view.
  35 //
  36 // To flatten the WebUI resources, tags for JS and CSS resources are replaced
  37 // with retrieved resources. For example, if a WebUI HTML resource looks like:
  38 // <html>
  39 //   <script src='chrome://javascript.js></script>
  40 //   <link rel="stylesheet" href="chrome://stylesheet.css">
  41 // </html>
  42 // the flattened version would look like:
  43 // <html>
  44 //   <script>[Content of chrome://javascript.js]</script>
  45 //   <style>[Content of chrome://stylesheet.css]</style>
  46 // </html>
  47 @interface CRWWebUIPageBuilder : NSObject
  48
  49 // Designated initializer.
  50 - (instancetype)initWithDelegate:(id<CRWWebUIPageBuilderDelegate>)delegate;
  51
  52 // Builds and flattens page for webUIURL, and invokes completionHandler with the
  53 // result.
  54 - (void)buildWebUIPageForURL:(const GURL&)webUIURL
  55            completionHandler:(web::WebUIPageCompletion)completionHandler;
  56
  57 @end
  58
  59 #endif  // IOS_WEB_WEBUI_CRW_WEB_UI_PAGE_BUILDER_H_