Add the ability to navigate with swipe gesture (#757)

* Add the ability to navigate with swipe gesture

On macOS, add an API to enable or disable
backward and forward navigation gestures.

For details, see <https://developer.apple.com/documentation/webkit/wkwebview/1414995-allowsbackforwardnavigationgestu>

Signed-off-by: pan93412 <pan93412@gmail.com>

* Update .changes/allow-back-forward-gesture.md

Signed-off-by: pan93412 <pan93412@gmail.com>

.changes/allow-back-forward-gesture.md

@@ -0,0 +1,5 @@
+---
+"wry": minor
+---
+
+On macOS, add an API to enable or disable backward and forward navigation gestures.

src/webview/mod.rs

@@ -215,6 +215,14 @@ pub struct WebViewAttributes {
   ///
   /// This configuration only impacts macOS.
   pub accept_first_mouse: bool,
+
+  /// Indicates whether horizontal swipe gestures trigger backward and forward page navigation.
+  ///
+  /// ## Platform-specific
+  ///
+  /// This configuration only impacts macOS.
+  /// [Documentation](https://developer.apple.com/documentation/webkit/wkwebview/1414995-allowsbackforwardnavigationgestu).
+  pub back_forward_navigation_gestures: bool,
 }
 
 impl Default for WebViewAttributes {
@@ -241,6 +249,7 @@ impl Default for WebViewAttributes {
       devtools: false,
       zoom_hotkeys_enabled: false,
       accept_first_mouse: false,
+      back_forward_navigation_gestures: false,
     }
   }
 }
@@ -295,6 +304,17 @@ impl<'a> WebViewBuilder<'a> {
     })
   }
 
+  /// Indicates whether horizontal swipe gestures trigger backward and forward page navigation.
+  ///
+  /// ## Platform-specific
+  ///
+  /// This configuration only impacts macOS.
+  /// [Documentation](https://developer.apple.com/documentation/webkit/wkwebview/1414995-allowsbackforwardnavigationgestu).
+  pub fn with_back_forward_navigation_gestures(mut self, gesture: bool) -> Self {
+    self.webview.back_forward_navigation_gestures = gesture;
+    self
+  }
+
   /// Sets whether the WebView should be transparent.
   ///
   /// ## Platform-specific:

src/webview/wkwebview/mod.rs

@@ -343,6 +343,13 @@ impl InnerWebView {
         let _: () = msg_send![webview, initWithFrame:frame configuration:config];
       }
 
+      // allowsBackForwardNavigation
+      #[cfg(target_os = "macos")]
+      {
+        let value = attributes.back_forward_navigation_gestures;
+        let _: () = msg_send![webview, setAllowsBackForwardNavigationGestures: value];
+      }
+
       // Message handler
       let ipc_handler_ptr = if let Some(ipc_handler) = attributes.ipc_handler {
         let cls = ClassDecl::new("WebViewDelegate", class!(NSObject));