fix(event): clear residual js listeners (#8916 )

.changes/fix-clear-residual-listeners.md

@@ -0,0 +1,6 @@
+---
+"tauri": patch:bug
+---
+
+Adds the `unlisten_all_js` method to struct `Webview` and calls it in on_page_load_handler when the corresponding webview window is refreshed.
+This will only clean up all `js_listeners` for the window that was refreshed, and will not affect other windows.

core/tauri/src/event/listener.rs

@@ -271,6 +271,18 @@ impl Listeners {
     }
   }
 
+  pub(crate) fn unlisten_all_js(&self, source_webview_label: &str) {
+    let inner_listeners = self.inner.as_ref();
+    let mut js_listeners = inner_listeners.js_event_listeners.lock().unwrap();
+    js_listeners
+      .iter_mut()
+      .for_each(|(webview_label, listener)| {
+        if webview_label == source_webview_label {
+          listener.clear()
+        }
+      })
+  }
+
   pub(crate) fn has_js_listener<F: Fn(&EventTarget) -> bool>(
     &self,
     event: &str,

core/tauri/src/event/mod.rs

@@ -230,6 +230,24 @@ pub fn unlisten_js_script(
   )
 }
 
+pub fn unlisten_all_js_script(listeners_object_name: &str) -> String {
+  format!(
+    r#"
+      (function () {{
+          var listenersObjectName = '{}';
+          if (window[listenersObjectName]) {{
+              for (var prop in window[listenersObjectName]) {{
+                  if (window[listenersObjectName].hasOwnProperty(prop)) {{
+                      window[listenersObjectName][prop] = undefined;
+                  }}
+              }}
+          }}
+        }})();
+      "#,
+    listeners_object_name
+  )
+}
+
 pub fn event_initialization_script(function: &str, listeners: &str) -> String {
   format!(
     "

core/tauri/src/webview/mod.rs

@@ -568,17 +568,27 @@ tauri::Builder::default()
       }));
     }
 
-    if let Some(on_page_load_handler) = self.on_page_load_handler.take() {
-      let label = pending.label.clone();
-      let manager = manager.manager_owned();
-      pending
-        .on_page_load_handler
-        .replace(Box::new(move |url, event| {
-          if let Some(w) = manager.get_webview(&label) {
-            on_page_load_handler(w, PageLoadPayload { url: &url, event });
+    let label_ = pending.label.clone();
+    let manager_ = manager.manager_owned();
+    pending
+      .on_page_load_handler
+      .replace(Box::new(move |url, event| {
+        if let Some(w) = manager_.get_webview(&label_) {
+          if let PageLoadEvent::Finished = event {
+            match w.unlisten_all_js() {
+              Ok(_) => {
+                // println!("Clear all residual js listeners when page load.")
+              }
+              Err(e) => {
+                println!("Failed to clear residual js listeners when page load: {e}")
+              }
+            };
           }
-        }));
-    }
+          if let Some(handler) = self.on_page_load_handler.as_ref() {
+            handler(w, PageLoadPayload { url: &url, event });
+          }
+        }
+      }));
 
     manager.manager().webview.prepare_webview(
       manager,
@@ -1317,6 +1327,17 @@ fn main() {
     Ok(())
   }
 
+  /// Unregister all JS event listeners.
+  pub(crate) fn unlisten_all_js(&self) -> crate::Result<()> {
+    let listeners: &crate::event::Listeners = self.manager().listeners();
+    listeners.unlisten_all_js(self.label());
+    self.eval(&crate::event::unlisten_all_js_script(
+      listeners.listeners_object_name(),
+    ))?;
+
+    Ok(())
+  }
+
   pub(crate) fn emit_js(&self, emit_args: &EmitArgs, target: &EventTarget) -> crate::Result<()> {
     self.eval(&crate::event::emit_js_script(
       self.manager().listeners().function_name(),