Merge pull request #202 from Jafz2001/fix/macos-plugin-editor-windows

Keep macOS plugin editors out of the Dock

crates/vst3-host/src/ffi.rs

@@ -1749,7 +1749,7 @@ impl EditorLink {
 mod window {
     use objc2::rc::Retained;
     use objc2::{MainThreadMarker, MainThreadOnly};
-    use objc2_app_kit::{NSApplication, NSBackingStoreType, NSFloatingWindowLevel, NSWindow, NSWindowStyleMask};
+    use objc2_app_kit::{NSApplication, NSBackingStoreType, NSFloatingWindowLevel, NSWindow, NSWindowCollectionBehavior, NSWindowStyleMask};
     use objc2_foundation::{NSPoint, NSRect, NSSize, NSString};
     use std::ffi::{c_char, c_void};
 
@@ -1780,7 +1780,10 @@ mod window {
             let mtm = MainThreadMarker::new().ok_or_else(|| "not on the main thread".to_string())?;
             let _app = NSApplication::sharedApplication(mtm);
             let rect = NSRect::new(NSPoint::new(200.0, 200.0), NSSize::new(w, h));
-            let style = NSWindowStyleMask::Titled | NSWindowStyleMask::Closable | NSWindowStyleMask::Miniaturizable;
+            // Plugin editors are transient windows. In particular they must not be
+            // minimizable: minimized NSWindows become persistent thumbnails in the macOS Dock,
+            // which made every editor visited in a session look like another running app.
+            let style = NSWindowStyleMask::Titled | NSWindowStyleMask::Closable;
             // SAFETY: a freshly allocated window on the main thread; valid rect and style.
             let window = unsafe {
                 NSWindow::initWithContentRect_styleMask_backing_defer(NSWindow::alloc(mtm), rect, style, NSBackingStoreType::Buffered, false)
@@ -1791,6 +1794,8 @@ mod window {
             window.setTitle(&NSString::from_str(title));
             window.setLevel(NSFloatingWindowLevel);
             window.setHidesOnDeactivate(true);
+            window.setExcludedFromWindowsMenu(true);
+            window.setCollectionBehavior(NSWindowCollectionBehavior::Transient | NSWindowCollectionBehavior::IgnoresCycle);
             window.center();
             Ok(HostWindow { window: Retained::into_raw(window) })
         }