Implement 'reload' and 'stopLoading' methods

Summary:
@public

This diff implements the `reload` and `stopLoading` methods for `WKWebView`. Their functionality is self-explanatory.

Reviewed By: shergin

Differential Revision: D6369292

fbshipit-source-id: ba176f4406e0a67606406f36dd66f7615f4796c3

React/Views/RCTWKWebView.h

@@ -27,5 +27,7 @@
 - (void)injectJavaScript:(NSString *)script;
 - (void)goForward;
 - (void)goBack;
+- (void)reload;
+- (void)stopLoading;
 
 @end

React/Views/RCTWKWebView.m

@@ -270,4 +270,24 @@ - (void)goBack
   [_webView goBack];
 }
 
+- (void)reload
+{
+  /**
+   * When the initial load fails due to network connectivity issues,
+   * [_webView reload] doesn't reload the webpage. Therefore, we must
+   * manually call [_webView loadRequest:request].
+   */
+  NSURLRequest *request = [RCTConvert NSURLRequest:self.source];
+  if (request.URL && !_webView.URL.absoluteString.length) {
+    [_webView loadRequest:request];
+  }
+  else {
+    [_webView reload];
+  }
+}
+
+- (void)stopLoading
+{
+  [_webView stopLoading];
+}
 @end

React/Views/RCTWKWebViewManager.m

@@ -81,4 +81,28 @@ - (UIView *)view
   }];
 }
 
+RCT_EXPORT_METHOD(reload:(nonnull NSNumber *)reactTag)
+{
+  [self.bridge.uiManager addUIBlock:^(__unused RCTUIManager *uiManager, NSDictionary<NSNumber *, RCTWKWebView *> *viewRegistry) {
+    RCTWKWebView *view = viewRegistry[reactTag];
+    if (![view isKindOfClass:[RCTWKWebView class]]) {
+      RCTLogError(@"Invalid view returned from registry, expecting RCTWebView, got: %@", view);
+    } else {
+      [view reload];
+    }
+  }];
+}
+
+RCT_EXPORT_METHOD(stopLoading:(nonnull NSNumber *)reactTag)
+{
+  [self.bridge.uiManager addUIBlock:^(__unused RCTUIManager *uiManager, NSDictionary<NSNumber *, RCTWKWebView *> *viewRegistry) {
+    RCTWKWebView *view = viewRegistry[reactTag];
+    if (![view isKindOfClass:[RCTWKWebView class]]) {
+      RCTLogError(@"Invalid view returned from registry, expecting RCTWebView, got: %@", view);
+    } else {
+      [view stopLoading];
+    }
+  }];
+}
+
 @end