feat: implement set_content_protection, closes #550 (#551)

* feat: implement set_content_protection

* fmt

* Update content_protection.rs

* add changefile

* Apply suggestions from code review

* remove dedicated example

* Update src/platform_impl/windows/window.rs

* fmt

* Delete content_protection.rs

.changes/content-protection.md

@@ -0,0 +1,5 @@
+---
+"tao": "minor"
+---
+
+Add `Window::set_content_protection` for macOS and Windows.

examples/window_debug.rs

@@ -34,10 +34,12 @@ fn main() {
   eprintln!("  (X) Toggle maximized");
   eprintln!("  (T) Toggle always on top");
   eprintln!("  (B) Toggle always on bottom");
+  eprintln!("  (C) Toggle content protection");
 
   let mut always_on_bottom = false;
   let mut always_on_top = false;
   let mut visible = true;
+  let mut content_protection = false;
 
   event_loop.run(move |event, _, control_flow| {
     *control_flow = ControlFlow::Wait;
@@ -133,6 +135,10 @@ fn main() {
           always_on_bottom = !always_on_bottom;
           window.set_always_on_bottom(always_on_bottom);
         }
+        "c" => {
+          content_protection = !content_protection;
+          window.set_content_protection(content_protection);
+        }
         _ => (),
       },
       Event::WindowEvent {

src/platform_impl/android/ndk_glue.rs

@@ -2,8 +2,8 @@
 // Copyright 2021-2022 Tauri Programme within The Commons Conservancy
 // SPDX-License-Identifier: Apache-2.0
 
-pub use jni;
 pub use jni::{
+  self,
   objects::{GlobalRef, JClass, JMap, JObject, JString},
   sys::jobject,
   JNIEnv,

src/platform_impl/macos/window.rs

@@ -1253,6 +1253,12 @@ impl UnownedWindow {
     let state = self.shared_state.lock().unwrap();
     state.current_theme
   }
+
+  pub fn set_content_protection(&self, enabled: bool) {
+    unsafe {
+      let _: () = msg_send![*self.ns_window, setSharingType: !enabled as i32];
+    }
+  }
 }
 
 impl WindowExtMacOS for UnownedWindow {

src/platform_impl/windows/window.rs

@@ -821,6 +821,19 @@ impl Window {
     self.window_state.lock().skip_taskbar = skip;
     unsafe { set_skip_taskbar(self.hwnd(), skip) };
   }
+
+  pub fn set_content_protection(&self, enabled: bool) {
+    unsafe {
+      SetWindowDisplayAffinity(
+        self.hwnd(),
+        if enabled {
+          WDA_EXCLUDEFROMCAPTURE
+        } else {
+          WDA_NONE
+        },
+      );
+    }
+  }
 }
 
 impl Drop for Window {

src/window.rs

@@ -905,6 +905,16 @@ impl Window {
   pub fn theme(&self) -> Theme {
     self.window.theme()
   }
+
+  /// Prevents the window contents from being captured by other apps.
+  ///
+  /// ## Platform-specific
+  ///
+  /// - **iOS / Android / Linux:** Unsupported.
+  pub fn set_content_protection(&self, enabled: bool) {
+    #[cfg(any(target_os = "macos", target_os = "windows"))]
+    self.window.set_content_protection(enabled);
+  }
 }
 
 /// Cursor functions.