fix: `setContentProtection(true)` after hide on Windows (#45868)

fix: content protection after hide on Windows

https://chromium-review.googlesource.com/c/chromium/src/+/5789117

shell/browser/api/electron_api_base_window.cc

@@ -724,6 +724,10 @@ void BaseWindow::SetContentProtection(bool enable) {
   return window_->SetContentProtection(enable);
 }
 
+bool BaseWindow::IsContentProtected() const {
+  return window_->IsContentProtected();
+}
+
 void BaseWindow::SetFocusable(bool focusable) {
   return window_->SetFocusable(focusable);
 }
@@ -1261,6 +1265,7 @@ void BaseWindow::BuildPrototype(v8::Isolate* isolate,
       .SetMethod("isDocumentEdited", &BaseWindow::IsDocumentEdited)
       .SetMethod("setIgnoreMouseEvents", &BaseWindow::SetIgnoreMouseEvents)
       .SetMethod("setContentProtection", &BaseWindow::SetContentProtection)
+      .SetMethod("_isContentProtected", &BaseWindow::IsContentProtected)
       .SetMethod("setFocusable", &BaseWindow::SetFocusable)
       .SetMethod("isFocusable", &BaseWindow::IsFocusable)
       .SetMethod("setMenu", &BaseWindow::SetMenu)

shell/browser/api/electron_api_base_window.h

@@ -177,6 +177,7 @@ class BaseWindow : public gin_helper::TrackableObject<BaseWindow>,
   bool IsDocumentEdited() const;
   void SetIgnoreMouseEvents(bool ignore, gin_helper::Arguments* args);
   void SetContentProtection(bool enable);
+  bool IsContentProtected() const;
   void SetFocusable(bool focusable);
   bool IsFocusable() const;
   void SetMenu(v8::Isolate* isolate, v8::Local<v8::Value> menu);

shell/browser/native_window.h

@@ -186,6 +186,7 @@ class NativeWindow : public base::SupportsUserData,
   virtual bool IsDocumentEdited() const;
   virtual void SetIgnoreMouseEvents(bool ignore, bool forward) = 0;
   virtual void SetContentProtection(bool enable) = 0;
+  virtual bool IsContentProtected() const = 0;
   virtual void SetFocusable(bool focusable) {}
   virtual bool IsFocusable() const;
   virtual void SetMenu(ElectronMenuModel* menu) {}

shell/browser/native_window_mac.h

@@ -110,6 +110,7 @@ class NativeWindowMac : public NativeWindow,
   bool IsHiddenInMissionControl() const override;
   void SetHiddenInMissionControl(bool hidden) override;
   void SetContentProtection(bool enable) override;
+  bool IsContentProtected() const override;
   void SetFocusable(bool focusable) override;
   bool IsFocusable() const override;
   void SetParentWindow(NativeWindow* parent) override;

shell/browser/native_window_mac.mm

@@ -1170,6 +1170,10 @@ void NativeWindowMac::SetContentProtection(bool enable) {
       setSharingType:enable ? NSWindowSharingNone : NSWindowSharingReadOnly];
 }
 
+bool NativeWindowMac::IsContentProtected() const {
+  return [window_ sharingType] == NSWindowSharingNone;
+}
+
 void NativeWindowMac::SetFocusable(bool focusable) {
   // No known way to unfocus the window if it had the focus. Here we do not
   // want to call Focus(false) because it moves the window to the back, i.e.

shell/browser/native_window_views.cc

@@ -1317,17 +1317,15 @@ void NativeWindowViews::SetIgnoreMouseEvents(bool ignore, bool forward) {
 
 void NativeWindowViews::SetContentProtection(bool enable) {
 #if BUILDFLAG(IS_WIN)
-  HWND hwnd = GetAcceleratedWidget();
-  DWORD affinity = enable ? WDA_EXCLUDEFROMCAPTURE : WDA_NONE;
-  ::SetWindowDisplayAffinity(hwnd, affinity);
-  if (!layered_) {
-    // Workaround to prevent black window on screen capture after hiding and
-    // showing the BrowserWindow.
-    LONG ex_style = ::GetWindowLong(hwnd, GWL_EXSTYLE);
-    ex_style |= WS_EX_LAYERED;
-    ::SetWindowLong(hwnd, GWL_EXSTYLE, ex_style);
-    layered_ = true;
-  }
+  widget()->native_widget_private()->SetAllowScreenshots(!enable);
+#endif
+}
+
+bool NativeWindowViews::IsContentProtected() const {
+#if BUILDFLAG(IS_WIN)
+  return !widget()->native_widget_private()->AreScreenshotsAllowed();
+#else  // Not implemented on Linux
+  return false;
 #endif
 }
 

shell/browser/native_window_views.h

@@ -116,6 +116,7 @@ class NativeWindowViews : public NativeWindow,
   double GetOpacity() const override;
   void SetIgnoreMouseEvents(bool ignore, bool forward) override;
   void SetContentProtection(bool enable) override;
+  bool IsContentProtected() const override;
   void SetFocusable(bool focusable) override;
   bool IsFocusable() const override;
   void SetMenu(ElectronMenuModel* menu_model) override;

spec/api-browser-window-spec.ts

@@ -296,6 +296,44 @@ describe('BrowserWindow module', () => {
     });
   });
 
+  ifdescribe(process.platform !== 'linux')('BrowserWindow.getContentProtection', () => {
+    afterEach(closeAllWindows);
+    it('can set content protection', async () => {
+      const w = new BrowserWindow({ show: false });
+      // @ts-expect-error This is a private API
+      expect(w._isContentProtected()).to.equal(false);
+
+      const shown = once(w, 'show');
+
+      w.show();
+      await shown;
+
+      w.setContentProtection(true);
+      // @ts-expect-error This is a private API
+      expect(w._isContentProtected()).to.equal(true);
+    });
+
+    it('does not remove content protection after the window is hidden and shown', async () => {
+      const w = new BrowserWindow({ show: false });
+
+      const hidden = once(w, 'hide');
+      const shown = once(w, 'show');
+
+      w.show();
+      await shown;
+
+      w.setContentProtection(true);
+
+      w.hide();
+      await hidden;
+      w.show();
+      await shown;
+
+      // @ts-expect-error This is a private API
+      expect(w._isContentProtected()).to.equal(true);
+    });
+  });
+
   describe('BrowserWindow.loadURL(url)', () => {
     let w: BrowserWindow;
     const scheme = 'other';