mac: Implement custom AppKit Enter Fullscreen transition.

chrome/browser/ui/cocoa/browser_window_enter_fullscreen_transition.mm

+// Copyright 2014 The Chromium Authors. All rights reserved.

[Andre, 2015/01/12 06:10:03]

2015

[erikchen, 2015/01/12 19:18:58]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "chrome/browser/ui/cocoa/browser_window_enter_fullscreen_transition.h"
+
+#include <QuartzCore/QuartzCore.h>
+
+#include "base/mac/scoped_cftyperef.h"
+#include "base/mac/scoped_nsobject.h"
+#include "base/mac/sdk_forward_declarations.h"
+
+namespace {
+
+NSString* const kPrimaryWindowAnimationID = @"PrimaryWindowAnimationID";
+NSString* const kSnapshotWindowAnimationID = @"SnapshotWindowAnimationID";
+NSString* const kAnimationIDKey = @"AnimationIDKey";
+
+// This class has two simultaneous animations to resize and reposition layers.
+// These animations must use the same timing function, otherwise there will be
+// visual discordance.
+NSString* const kTransformAnimationTimingFunction =
+    kCAMediaTimingFunctionEaseInEaseOut;
+
+}  // namespace
+
+@interface BrowserWindowEnterFullscreenTransition () {
+  // The window which is undergoing the fullscreen transition.
+  base::scoped_nsobject<NSWindow> _primaryWindow;
+
+  // A layer that holds a snapshot of the original state of |_primaryWindow|.
+  base::scoped_nsobject<CALayer> _snapshotLayer;
+
+  // A temporary window that holds |_snapshotLayer|.
+  base::scoped_nsobject<NSWindow> _snapshotWindow;
+
+  // The animation applied to |_snapshotLayer|.
+  base::scoped_nsobject<CAAnimationGroup> _snapshotAnimation;
+
+  // The animation applied to the root layer of |_primaryWindow|.
+  base::scoped_nsobject<CAAnimationGroup> _primaryWindowAnimation;
+
+  // The frame of the |_primaryWindow| before the transition began.
+  NSRect _primaryWindowInitialFrame;
+
+  // The background color of |_primaryWindow| before the transition began.
+  base::scoped_nsobject<NSColor> _primaryWindowInitialBackgroundColor;
+
+  // Whether |_primaryWindow| was opaque before the transition began.
+  BOOL _primaryWindowInitialOpaque;
+
+  // Whether the instance is in the process of changing the size of
+  // |_primaryWindow|.
+  BOOL _changingPrimaryWindowSize;
+
+  // The frame that |_primaryWindow| is expected to have after the transition
+  // is finished.
+  NSRect _primaryWindowFinalFrame;
+}
+
+// Takes a snapshot of |_primaryWindow| and puts it in |_snapshotLayer|.
+- (void)takeSnapshot;
+
+// Creates |_snapshotWindow| and adds |_snapshotLayer| to it.
+- (void)makeAndPrepareSnapshotWindow;
+
+// This method has several effects on |_primaryWindow|:
+//  - Saves current state.
+//  - Makes window transparent, with clear background.
+//  - Adds NSFullScreenWindowMask style mask.
+//  - Sets the size to the screen's size.
+- (void)preparePrimaryWindowForAnimation;
+
+// Applies the fullscreen animation to |_snapshotLayer|.
+- (void)animateSnapshotWindowWithDuration:(CGFloat)duration;
+
+// Applies the fullscreen animation to the root layer of |_primaryWindow|.
+- (void)animatePrimaryWindowWithDuration:(CGFloat)duration;
+
+// Override of CAAnimation delegate method.
+- (void)animationDidStop:(CAAnimation*)theAnimation finished:(BOOL)flag;
+
+// Returns the layer of the root view of |window|.
+- (CALayer*)rootLayerOfWindow:(NSWindow*)window;
+
+@end
+
+@implementation BrowserWindowEnterFullscreenTransition
+
+// -------------------------Public Methods----------------------------
+
+- (instancetype)initWithWindow:(NSWindow*)window {
+  DCHECK(window);
+  DCHECK([self rootLayerOfWindow:window]);
+  if ((self = [super init])) {
+    _primaryWindow.reset([window retain]);
+  }
+  return self;
+}
+
+- (void)dealloc {
+  [_snapshotAnimation setDelegate:nil];
+  [_primaryWindowAnimation setDelegate:nil];
+  [super dealloc];
+}
+
+- (NSArray*)customWindowsToEnterFullScreen {
+  [self takeSnapshot];
+  [self makeAndPrepareSnapshotWindow];
+  [self preparePrimaryWindowForAnimation];
+  return @[ _primaryWindow.get(), _snapshotWindow.get() ];
+}
+
+- (void)startCustomAnimationToEnterFullScreenWithDuration:
+    (NSTimeInterval)duration {
+  [self animateSnapshotWindowWithDuration:duration];
+  [self animatePrimaryWindowWithDuration:duration];
+}
+
+- (BOOL)shouldWindowBeUnconstrained {
+  return _changingPrimaryWindowSize;
+}
+
+// -------------------------Private Methods----------------------------
+
+- (void)takeSnapshot {
+  base::ScopedCFTypeRef<CGImageRef> windowSnapshot(CGWindowListCreateImage(
+      CGRectNull, kCGWindowListOptionIncludingWindow,
+      [_primaryWindow windowNumber], kCGWindowImageBoundsIgnoreFraming));
+  _snapshotLayer.reset([[CALayer alloc] init]);
+  [_snapshotLayer setFrame:NSRectToCGRect([_primaryWindow frame])];
+  [_snapshotLayer setContents:static_cast<id>(windowSnapshot.get())];
+  [_snapshotLayer setAnchorPoint:CGPointMake(0, 0)];
+  [_snapshotLayer setBackgroundColor:CGColorCreateGenericRGB(0, 0, 0, 0)];
+}
+
+- (void)makeAndPrepareSnapshotWindow {
+  _snapshotWindow.reset(
+      [[NSWindow alloc] initWithContentRect:[[_primaryWindow screen] frame]
+                                  styleMask:0
+                                    backing:NSBackingStoreBuffered
+                                      defer:NO]);
+  [[_snapshotWindow contentView] setWantsLayer:YES];
+  [_snapshotWindow setOpaque:NO];
+  [_snapshotWindow setBackgroundColor:[NSColor clearColor]];
+  [_snapshotWindow setAnimationBehavior:NSWindowAnimationBehaviorNone];
+
+  [_snapshotWindow orderFront:nil];
+  [[[_snapshotWindow contentView] layer] addSublayer:_snapshotLayer];
+  [_snapshotLayer setFrame:[_primaryWindow frame]];
+}
+
+- (void)preparePrimaryWindowForAnimation {
+  // Save initial state of |_primaryWindow|.
+  _primaryWindowInitialFrame = [_primaryWindow frame];
+  _primaryWindowInitialBackgroundColor.reset(
+      [[_primaryWindow backgroundColor] retain]);
+  _primaryWindowInitialOpaque = [_primaryWindow isOpaque];
+
+  _primaryWindowFinalFrame = [[_primaryWindow screen] frame];
+
+  // Make |_primaryWindow| invisible. This must happen before the window is
+  // resized.
+  [_primaryWindow setOpaque:NO];
+  [_primaryWindow setBackgroundColor:[NSColor clearColor]];
+  CALayer* rootLayer = [self rootLayerOfWindow:_primaryWindow];
+  rootLayer.opacity = 0;
+
+  // As soon as the style mask includes the flag NSFullScreenWindowMask, the
+  // window is expected to receive fullscreen layout. This must be set before
+  // the window is resized, as that causes a relayout.
+  [_primaryWindow
+      setStyleMask:[_primaryWindow styleMask] | NSFullScreenWindowMask];
+
+  // Resize |_primaryWindow|.
+  _changingPrimaryWindowSize = YES;
+  [_primaryWindow setFrame:_primaryWindowFinalFrame display:YES];
+  _changingPrimaryWindowSize = NO;
+}
+
+- (void)animateSnapshotWindowWithDuration:(CGFloat)duration {
+  // Move the snapshot layer until it's bottom-left corner is at the
+  // bottom-left corner of the screen.
+  CABasicAnimation* positionAnimation =
+      [CABasicAnimation animationWithKeyPath:@"position"];
+  positionAnimation.toValue = [NSValue valueWithPoint:NSMakePoint(0, 0)];

[Andre, 2015/01/12 06:10:03]

NSZeroPoint

[erikchen, 2015/01/12 19:18:58]

Done.

+  positionAnimation.timingFunction = [CAMediaTimingFunction
+      functionWithName:kTransformAnimationTimingFunction];
+
+  // Expand the bounds until it covers the screen.
+  NSRect finalBounds = NSMakeRect(0, 0, NSWidth(_primaryWindowFinalFrame),
+                                  NSHeight(_primaryWindowFinalFrame));
+  CABasicAnimation* boundsAnimation =
+      [CABasicAnimation animationWithKeyPath:@"bounds"];
+  boundsAnimation.toValue = [NSValue valueWithRect:finalBounds];
+  boundsAnimation.timingFunction = [CAMediaTimingFunction
+      functionWithName:kTransformAnimationTimingFunction];
+
+  // Fade out the snapshot layer.
+  CABasicAnimation* opacityAnimation =
+      [CABasicAnimation animationWithKeyPath:@"opacity"];
+  opacityAnimation.toValue = @(0);

[Andre, 2015/01/12 06:10:03]

@(0) is like -numberWithInt:, so this should be @(0.0) for -numberWithDouble: to
avoid a conversion.
Same with @(1) below.

[erikchen, 2015/01/12 19:18:58]

Done.

+  opacityAnimation.timingFunction =
+      [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];
+
+  // Fill forwards, and don't remove the animation. When the animation
+  // completes, the entire window will be removed.
+  CAAnimationGroup* group = [CAAnimationGroup animation];
+  group.removedOnCompletion = NO;
+  group.fillMode = kCAFillModeForwards;
+  group.animations = @[ positionAnimation, boundsAnimation, opacityAnimation ];
+  group.duration = duration;
+  [group setValue:kSnapshotWindowAnimationID forKey:kAnimationIDKey];
+  group.delegate = self;
+
+  _snapshotAnimation.reset([group retain]);
+  [_snapshotLayer addAnimation:group forKey:nil];
+}
+
+- (void)animatePrimaryWindowWithDuration:(CGFloat)duration {
+  // As soon as the window is downsized, the opacity should be set back to 1.
+  // There are a couple of ways to do this. The easiest is to just have a dummy
+  // animation as part of the same animation group.
+  CABasicAnimation* opacityAnimation =
+      [CABasicAnimation animationWithKeyPath:@"opacity"];
+  opacityAnimation.fromValue = @(1);
+  opacityAnimation.toValue = @(1);
+
+  // Downsize the primary window, and the increase the size until it reaches it
+  // expected end size.
+  NSRect initialFrame = _primaryWindowInitialFrame;
+  NSRect endFrame = _primaryWindowFinalFrame;
+  CGFloat xScale = initialFrame.size.width / endFrame.size.width;
+  CGFloat yScale = initialFrame.size.height / endFrame.size.height;

[Andre, 2015/01/12 06:10:03]

Use NSWidth and NSHeight for consistency.

[erikchen, 2015/01/12 19:18:58]

Done.

[Andre, 2015/01/12 19:27:20]

Forgot to change this?

[erikchen, 2015/01/12 19:31:57]

Oops! Done.

+  CATransform3D initial = CATransform3DMakeScale(xScale, yScale, 1);
+  CABasicAnimation* transformAnimation =
+      [CABasicAnimation animationWithKeyPath:@"transform"];
+  transformAnimation.fromValue = [NSValue valueWithCATransform3D:initial];
+  transformAnimation.toValue =
+      [NSValue valueWithCATransform3D:CATransform3DIdentity];
+  transformAnimation.timingFunction = [CAMediaTimingFunction
+      functionWithName:kTransformAnimationTimingFunction];
+
+  // Animate the primary window to its final position.
+  CABasicAnimation* positionAnimation =
+      [CABasicAnimation animationWithKeyPath:@"position"];
+  CGPoint initialCenter =
+      CGPointMake(CGRectGetMidX(initialFrame), CGRectGetMidY(initialFrame));
+  CGPoint finalCenter =
+      CGPointMake(CGRectGetMidX(endFrame), CGRectGetMidY(endFrame));

[Andre, 2015/01/12 06:10:03]

Mixing CG and NS works ok on 64-bits, but it would be more correct to stay
in NSPoint/NSRect and use NSMidX/NSMidY.
Reads better too.

[erikchen, 2015/01/12 19:18:58]

You're right. Changed.

+  positionAnimation.fromValue = [NSValue valueWithPoint:initialCenter];
+  positionAnimation.toValue = [NSValue valueWithPoint:finalCenter];
+  positionAnimation.timingFunction = [CAMediaTimingFunction
+      functionWithName:kTransformAnimationTimingFunction];
+
+  CAAnimationGroup* group = [CAAnimationGroup animation];
+  group.removedOnCompletion = NO;
+  group.fillMode = kCAFillModeForwards;
+  group.animations =
+      @[ transformAnimation, opacityAnimation, positionAnimation ];
+  group.duration = duration;
+  [group setValue:kPrimaryWindowAnimationID forKey:kAnimationIDKey];
+  group.delegate = self;
+
+  _primaryWindowAnimation.reset([group retain]);
+  CALayer* root = [self rootLayerOfWindow:_primaryWindow];
+
+  [root addAnimation:group forKey:kPrimaryWindowAnimationID];
+}
+
+- (void)animationDidStop:(CAAnimation*)theAnimation finished:(BOOL)flag {
+  NSString* animationID = [theAnimation valueForKey:kAnimationIDKey];
+  if ([animationID isEqual:kSnapshotWindowAnimationID]) {
+    [_snapshotWindow orderOut:nil];
+    _snapshotWindow.reset();
+    _snapshotLayer.reset();
+    return;
+  }
+
+  if ([animationID isEqual:kPrimaryWindowAnimationID]) {
+    [_primaryWindow setOpaque:YES];
+    [_primaryWindow setBackgroundColor:_primaryWindowInitialBackgroundColor];
+    CALayer* root = [self rootLayerOfWindow:_primaryWindow];
+    root.opacity = 1;
+    [root removeAnimationForKey:kPrimaryWindowAnimationID];
+  }
+}
+
+- (CALayer*)rootLayerOfWindow:(NSWindow*)window {
+  return [[[window contentView] superview] layer];
+}
+
+@end