fix: clean up implementations of titleBarStyle (#27489)

* Rewrite titleBarStyle impls with WindowButtonsView

* Remove fullscreenWindowTitle option

* Make buttons show correctly under RTL

* Fix docs about traffic lights position

* Fix test on fullscreen resizable

* Fix button states with closabe/minimizable/fullscreenable

* Fix typo

* Deprecate the fullscreenWindowTitle option

shell/browser/ui/cocoa/electron_ns_window_delegate.mm

@@ -91,14 +91,17 @@ using TitleBarStyle = electron::NativeWindowMac::TitleBarStyle;
 
 - (void)windowDidBecomeMain:(NSNotification*)notification {
   shell_->NotifyWindowFocus();
+  shell_->RedrawTrafficLights();
 }
 
 - (void)windowDidResignMain:(NSNotification*)notification {
   shell_->NotifyWindowBlur();
+  shell_->RedrawTrafficLights();
 }
 
 - (void)windowDidBecomeKey:(NSNotification*)notification {
   shell_->NotifyWindowIsKeyChanged(true);
+  shell_->RedrawTrafficLights();
 }
 
 - (void)windowDidResignKey:(NSNotification*)notification {
@@ -110,6 +113,7 @@ using TitleBarStyle = electron::NativeWindowMac::TitleBarStyle;
     return;
 
   shell_->NotifyWindowIsKeyChanged(false);
+  shell_->RedrawTrafficLights();
 }
 
 - (NSSize)windowWillResize:(NSWindow*)sender toSize:(NSSize)frameSize {
@@ -151,9 +155,6 @@ using TitleBarStyle = electron::NativeWindowMac::TitleBarStyle;
 - (void)windowDidResize:(NSNotification*)notification {
   [super windowDidResize:notification];
   shell_->NotifyWindowResize();
-  if (shell_->title_bar_style() == TitleBarStyle::kHidden) {
-    shell_->RedrawTrafficLights();
-  }
 }
 
 - (void)windowWillMove:(NSNotification*)notification {
@@ -212,75 +213,23 @@ using TitleBarStyle = electron::NativeWindowMac::TitleBarStyle;
 }
 
 - (void)windowWillEnterFullScreen:(NSNotification*)notification {
-  // Setting resizable to true before entering fullscreen
+  shell_->NotifyWindowWillEnterFullScreen();
+  // Setting resizable to true before entering fullscreen.
   is_resizable_ = shell_->IsResizable();
   shell_->SetResizable(true);
-  // Hide the native toolbar before entering fullscreen, so there is no visual
-  // artifacts.
-  if (shell_->title_bar_style() == TitleBarStyle::kHiddenInset) {
-    NSWindow* window = shell_->GetNativeWindow().GetNativeNSWindow();
-    [window setToolbar:nil];
-  }
 }
 
 - (void)windowDidEnterFullScreen:(NSNotification*)notification {
   shell_->NotifyWindowEnterFullScreen();
-
-  // For frameless window we don't show set title for normal mode since the
-  // titlebar is expected to be empty, but after entering fullscreen mode we
-  // have to set one, because title bar is visible here.
-  NSWindow* window = shell_->GetNativeWindow().GetNativeNSWindow();
-  if ((shell_->transparent() || !shell_->has_frame()) &&
-      // FIXME(zcbenz): Showing titlebar for hiddenInset window is weird under
-      // fullscreen mode.
-      // Show title if fullscreen_window_title flag is set
-      (shell_->title_bar_style() != TitleBarStyle::kHiddenInset ||
-       shell_->fullscreen_window_title())) {
-    [window setTitleVisibility:NSWindowTitleVisible];
-  }
-
-  // Restore the native toolbar immediately after entering fullscreen, if we
-  // do this before leaving fullscreen, traffic light buttons will be jumping.
-  if (shell_->title_bar_style() == TitleBarStyle::kHiddenInset) {
-    base::scoped_nsobject<NSToolbar> toolbar(
-        [[NSToolbar alloc] initWithIdentifier:@"titlebarStylingToolbar"]);
-    [toolbar setShowsBaselineSeparator:NO];
-    [window setToolbar:toolbar];
-
-    // Set window style to hide the toolbar, otherwise the toolbar will show
-    // in fullscreen mode.
-    [window setTitlebarAppearsTransparent:NO];
-    shell_->SetStyleMask(true, NSWindowStyleMaskFullSizeContentView);
-  }
 }
 
 - (void)windowWillExitFullScreen:(NSNotification*)notification {
-  // Restore the titlebar visibility.
-  NSWindow* window = shell_->GetNativeWindow().GetNativeNSWindow();
-  if ((shell_->transparent() || !shell_->has_frame()) &&
-      (shell_->title_bar_style() != TitleBarStyle::kHiddenInset ||
-       shell_->fullscreen_window_title())) {
-    [window setTitleVisibility:NSWindowTitleHidden];
-  }
-
-  // Turn off the style for toolbar.
-  if (shell_->title_bar_style() == TitleBarStyle::kHiddenInset) {
-    shell_->SetStyleMask(false, NSWindowStyleMaskFullSizeContentView);
-    [window setTitlebarAppearsTransparent:YES];
-  }
-  shell_->SetExitingFullScreen(true);
-  if (shell_->title_bar_style() == TitleBarStyle::kHidden) {
-    shell_->RedrawTrafficLights();
-  }
+  shell_->NotifyWindowWillLeaveFullScreen();
 }
 
 - (void)windowDidExitFullScreen:(NSNotification*)notification {
   shell_->SetResizable(is_resizable_);
   shell_->NotifyWindowLeaveFullScreen();
-  shell_->SetExitingFullScreen(false);
-  if (shell_->title_bar_style() == TitleBarStyle::kHidden) {
-    shell_->RedrawTrafficLights();
-  }
 }
 
 - (void)windowWillClose:(NSNotification*)notification {

shell/browser/ui/cocoa/window_buttons_view.h

@@ -0,0 +1,31 @@
+// Copyright (c) 2021 Microsoft, Inc.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+#ifndef SHELL_BROWSER_UI_COCOA_WINDOW_BUTTONS_VIEW_H_
+#define SHELL_BROWSER_UI_COCOA_WINDOW_BUTTONS_VIEW_H_
+
+#import <Cocoa/Cocoa.h>
+
+#include "base/mac/scoped_nsobject.h"
+#include "base/optional.h"
+#include "ui/gfx/geometry/point.h"
+
+// Custom Quit, Minimize and Full Screen button container for frameless
+// windows.
+@interface WindowButtonsView : NSView {
+ @private
+  BOOL mouse_inside_;
+  BOOL show_on_hover_;
+  BOOL is_rtl_;
+  gfx::Point margin_;
+  base::scoped_nsobject<NSTrackingArea> tracking_area_;
+}
+
+- (id)initWithMargin:(const base::Optional<gfx::Point>&)margin;
+- (void)setMargin:(const base::Optional<gfx::Point>&)margin;
+- (void)setShowOnHover:(BOOL)yes;
+- (void)setNeedsDisplayForButtons;
+@end
+
+#endif  // SHELL_BROWSER_UI_COCOA_WINDOW_BUTTONS_VIEW_H_

shell/browser/ui/cocoa/window_buttons_view.mm

@@ -0,0 +1,119 @@
+// Copyright (c) 2021 Microsoft, Inc.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+#include "shell/browser/ui/cocoa/window_buttons_view.h"
+
+#include "base/i18n/rtl.h"
+#include "base/logging.h"
+#include "base/stl_util.h"
+#include "ui/gfx/mac/coordinate_conversion.h"
+
+namespace {
+
+const CGFloat kButtonPadding = 20.;
+
+const NSWindowButton kButtonTypes[] = {
+    NSWindowCloseButton,
+    NSWindowMiniaturizeButton,
+    NSWindowZoomButton,
+};
+
+}  // namespace
+
+@implementation WindowButtonsView
+
+- (id)initWithMargin:(const base::Optional<gfx::Point>&)margin {
+  self = [super initWithFrame:NSZeroRect];
+  [self setMargin:margin];
+
+  mouse_inside_ = false;
+  show_on_hover_ = false;
+  is_rtl_ = base::i18n::IsRTL();
+
+  for (size_t i = 0; i < base::size(kButtonTypes); ++i) {
+    NSButton* button = [NSWindow standardWindowButton:kButtonTypes[i]
+                                         forStyleMask:NSWindowStyleMaskTitled];
+    [button setTag:i];
+    int left_index = is_rtl_ ? base::size(kButtonTypes) - i - 1 : i;
+    [button setFrameOrigin:NSMakePoint(left_index * kButtonPadding, 0)];
+    [self addSubview:button];
+  }
+
+  NSView* last_button =
+      is_rtl_ ? [[self subviews] firstObject] : [[self subviews] lastObject];
+  [self setFrameSize:NSMakeSize(last_button.frame.origin.x +
+                                    last_button.frame.size.width,
+                                last_button.frame.size.height)];
+  [self setNeedsDisplayForButtons];
+
+  return self;
+}
+
+- (void)setMargin:(const base::Optional<gfx::Point>&)margin {
+  margin_ = margin.value_or(gfx::Point(7, 3));
+}
+
+- (void)setShowOnHover:(BOOL)yes {
+  show_on_hover_ = yes;
+  [self setNeedsDisplayForButtons];
+}
+
+- (void)setNeedsDisplayForButtons {
+  for (NSView* subview in self.subviews) {
+    [subview setHidden:(show_on_hover_ && !mouse_inside_)];
+    [subview setNeedsDisplay:YES];
+  }
+}
+
+- (void)removeFromSuperview {
+  [super removeFromSuperview];
+  mouse_inside_ = NO;
+}
+
+- (void)viewDidMoveToWindow {
+  // Stay in upper left corner.
+  CGFloat y =
+      self.superview.frame.size.height - self.frame.size.height - margin_.y();
+  if (is_rtl_) {
+    CGFloat x =
+        self.superview.frame.size.width - self.frame.size.width - margin_.x();
+    [self setAutoresizingMask:NSViewMinXMargin | NSViewMinYMargin];
+    [self setFrameOrigin:NSMakePoint(x, y)];
+  } else {
+    [self setAutoresizingMask:NSViewMaxXMargin | NSViewMinYMargin];
+    [self setFrameOrigin:NSMakePoint(margin_.x(), y)];
+  }
+}
+
+- (BOOL)_mouseInGroup:(NSButton*)button {
+  return mouse_inside_;
+}
+
+- (void)updateTrackingAreas {
+  [super updateTrackingAreas];
+  if (tracking_area_)
+    [self removeTrackingArea:tracking_area_.get()];
+
+  tracking_area_.reset([[NSTrackingArea alloc]
+      initWithRect:NSZeroRect
+           options:NSTrackingMouseEnteredAndExited | NSTrackingActiveAlways |
+                   NSTrackingInVisibleRect
+             owner:self
+          userInfo:nil]);
+  [self addTrackingArea:tracking_area_.get()];
+}
+
+- (void)mouseEntered:(NSEvent*)event {
+  [super mouseEntered:event];
+  mouse_inside_ = YES;
+  [self setNeedsDisplayForButtons];
+}
+
+- (void)mouseExited:(NSEvent*)event {
+  [super mouseExited:event];
+  mouse_inside_ = NO;
+  [self setNeedsDisplayForButtons];
+}
+
+@end