Instant: Use only one hidden WebContents per profile.

chrome/browser/ui/cocoa/tab_contents/previewable_contents_controller.mm

-// Copyright 2011 The Chromium Authors. All rights reserved.
-// 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/tab_contents/previewable_contents_controller.h"
-
-#include "base/mac/bundle_locations.h"
-#include "chrome/browser/ui/cocoa/browser_window_controller.h"
-#include "chrome/browser/ui/cocoa/tab_contents/instant_preview_controller_mac.h"
-#include "chrome/browser/ui/cocoa/tab_contents/preview_drop_shadow_view.h"
-#include "content/public/browser/web_contents.h"
-#include "content/public/browser/web_contents_view.h"
-
-@interface PreviewableContentsController()
-- (void)viewDidResize:(NSNotification*)note;
-- (void)layoutViews;
-- (CGFloat)previewHeightInPixels;
-@end
-
-@implementation PreviewableContentsController
-
-@synthesize drawDropShadow = drawDropShadow_;
-@synthesize activeContainerOffset = activeContainerOffset_;
-
-- (id)initWithBrowser:(Browser*)browser
-     windowController:(BrowserWindowController*)windowController {
-  if ((self = [super init])) {
-    windowController_ = windowController;
-    scoped_nsobject<NSView> view([[NSView alloc] initWithFrame:NSZeroRect]);
-    [view setAutoresizingMask:NSViewHeightSizable | NSViewWidthSizable];
-    [view setAutoresizesSubviews:NO];
-    [[NSNotificationCenter defaultCenter]
-        addObserver:self
-           selector:@selector(viewDidResize:)
-               name:NSViewFrameDidChangeNotification
-             object:view];
-    [self setView:view];
-
-    activeContainer_.reset([[NSView alloc] initWithFrame:NSZeroRect]);
-    [view addSubview:activeContainer_];
-
-    instantPreviewController_.reset(
-        new InstantPreviewControllerMac(browser, windowController, self));
-  }
-  return self;
-}
-
-- (void)dealloc {
-  [[NSNotificationCenter defaultCenter] removeObserver:self];
-  [super dealloc];
-}
-
-- (void)setPreview:(content::WebContents*)preview
-            height:(CGFloat)height
-       heightUnits:(InstantSizeUnits)heightUnits
-    drawDropShadow:(BOOL)drawDropShadow {
-  // If drawing drop shadow, clip the bottom 1-px-thick separator out of
-  // preview.
-  // TODO(sail): remove this when GWS gives chrome the height without the
-  // separator.
-  if (drawDropShadow && heightUnits != INSTANT_SIZE_PERCENT)
-    --height;
-
-  if (previewContents_ == preview &&
-      previewHeight_ == height &&
-      previewHeightUnits_ == heightUnits &&
-      drawDropShadow_ == drawDropShadow) {
-    return;
-  }
-
-  // Remove any old preview contents before showing the new one.
-  if (previewContents_) {
-    [previewContents_->GetView()->GetNativeView() removeFromSuperview];
-    previewContents_->WasHidden();
-  }
-
-  previewContents_ = preview;
-  previewHeight_ = height;
-  previewHeightUnits_ = heightUnits;
-  drawDropShadow_ = drawDropShadow;
-
-  // Add the preview contents.
-  if (previewContents_) {
-    [[[self view] window] disableScreenUpdatesUntilFlush];
-    previewContents_->GetView()->SetAllowOverlappingViews(true);
-    [[self view] addSubview:previewContents_->GetView()->GetNativeView()];
-  }
-
-  if (drawDropShadow_) {
-    if (!dropShadowView_) {
-      dropShadowView_.reset(
-          [[PreviewDropShadowView alloc] initWithFrame:NSZeroRect]);
-      [[self view] addSubview:dropShadowView_];
-    }
-  } else {
-    [dropShadowView_ removeFromSuperview];
-    dropShadowView_.reset();
-  }
-
-  [self layoutViews];
-
-  if (previewContents_)
-    previewContents_->WasShown();
-}
-
-- (void)onActivateTabWithContents:(content::WebContents*)contents {
-  if (previewContents_ == contents) {
-    if (previewContents_) {
-      [previewContents_->GetView()->GetNativeView() removeFromSuperview];
-      previewContents_ = NULL;
-    }
-    [self setPreview:NULL
-              height:0
-         heightUnits:INSTANT_SIZE_PIXELS
-      drawDropShadow:NO];
-  }
-}
-
-- (BOOL)isShowingPreview {
-  return previewContents_ != nil;
-}
-
-- (InstantPreviewControllerMac*)instantPreviewController {
-  return instantPreviewController_.get();
-}
-
-- (NSView*)activeContainer {
-  return activeContainer_.get();
-}
-
-- (NSView*)dropShadowView {
-  return dropShadowView_.get();
-}
-
-- (void)setActiveContainerOffset:(CGFloat)activeContainerOffset {
-  if (activeContainerOffset_ == activeContainerOffset)
-    return;
-
-  activeContainerOffset_ = activeContainerOffset;
-  [self layoutViews];
-}
-
-- (void)viewDidResize:(NSNotification*)note {
-  [self layoutViews];
-}
-
-- (void)layoutViews {
-  NSRect bounds = [[self view] bounds];
-
-  if (previewContents_) {
-    NSRect previewFrame = bounds;
-    previewFrame.size.height = [self previewHeightInPixels];
-    previewFrame.origin.y = NSMaxY(bounds) - NSHeight(previewFrame);
-    [previewContents_->GetView()->GetNativeView() setFrame:previewFrame];
-
-    if (dropShadowView_) {
-      NSRect dropShadowFrame = bounds;
-      dropShadowFrame.size.height = [PreviewDropShadowView preferredHeight];
-      dropShadowFrame.origin.y =
-          NSMinY(previewFrame) - NSHeight(dropShadowFrame);
-      [dropShadowView_ setFrame:dropShadowFrame];
-    }
-  }
-
-  NSRect activeFrame = bounds;
-  activeFrame.size.height -= activeContainerOffset_;
-  [activeContainer_ setFrame:activeFrame];
-}
-
-- (CGFloat)previewHeightInPixels {
-  CGFloat height = NSHeight([[self view] bounds]);
-  switch (previewHeightUnits_) {
-    case INSTANT_SIZE_PERCENT:
-      return std::min(height, (height * previewHeight_) / 100);
-    case INSTANT_SIZE_PIXELS:
-      return std::min(height, previewHeight_);
-  }
-}
-
-@end