Upstream Chrome on iOS source code [5/11].

ios/chrome/browser/ui/ntp/new_tab_page_bar.mm

+// Copyright 2012 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 "ios/chrome/browser/ui/ntp/new_tab_page_bar.h"
+
+#import <QuartzCore/QuartzCore.h>
+#include <cmath>
+
+#include "base/logging.h"
+#include "base/mac/objc_property_releaser.h"
+#include "base/mac/scoped_nsobject.h"
+#import "ios/chrome/browser/ui/bookmarks/bookmark_utils_ios.h"
+#import "ios/chrome/browser/ui/ntp/new_tab_page_bar_button.h"
+#import "ios/chrome/browser/ui/ntp/new_tab_page_bar_item.h"
+#import "ios/chrome/browser/ui/rtl_geometry.h"
+#include "ios/chrome/browser/ui/ui_util.h"
+#import "ios/chrome/browser/ui/uikit_ui_util.h"
+#import "ui/gfx/ios/NSString+CrStringDrawing.h"
+#include "ui/gfx/scoped_ui_graphics_push_context_ios.h"
+
+namespace {
+
+const CGFloat kBarHeight = 48.0f;
+
+const CGFloat kRegularLayoutButtonWidth = 168;
+
+const int kOverlayViewColor = 0x5A7EF5;
+const int kOverlayColorWidth = 98;
+const int kNumberOfTabsIncognito = 2;
+
+}  // anonymous namespace
+
+@interface NewTabPageBar () {
+  base::scoped_nsobject<UIImageView> shadow_;
+}
+
+@property(nonatomic, readwrite, retain) NSArray* buttons;
+@property(nonatomic, readwrite, retain) UIButton* popupButton;
+
+- (void)setup;
+- (void)calculateButtonWidth;
+- (void)setupButton:(UIButton*)button;
+- (BOOL)useIconsInButtons;
+- (BOOL)showOverlay;
+@end
+
+@implementation NewTabPageBar {
+  // Tabbar buttons.
+  NSArray* buttons_;  // UIButton
+  NSArray* items_;    // NewTabPageBarItem
+  // Which button is currently selected.
+  NSUInteger selectedIndex_;
+  // Popup button helper, for iPhone labels.
+  UIButton* popupButton_;
+  // Don't allow tabbar animations on startup, only after first tap.
+  BOOL canAnimate_;
+  id<NewTabPageBarDelegate> delegate_;  // weak
+  // Logo view, used to center the tab buttons.
+  base::scoped_nsobject<UIImageView> logoView_;
+  // Overlay view, used to highlight the selected button.
+  base::scoped_nsobject<UIImageView> overlayView_;
+  // Overlay view, used to highlight the selected button.
+  base::scoped_nsobject<UIView> overlayColorView_;
+  // Width of a button.
+  CGFloat buttonWidth_;
+  // Percentage overlay sits over tab bar buttons.
+  CGFloat overlayPercentage_;
+
+  base::mac::ObjCPropertyReleaser propertyReleaser_NewTabPageBar_;
+}
+
+@synthesize items = items_;
+@synthesize selectedIndex = selectedIndex_;
+@synthesize popupButton = popupButton_;
+@synthesize buttons = buttons_;
+@synthesize delegate = delegate_;
+@synthesize overlayPercentage = overlayPercentage_;
+
+- (id)initWithFrame:(CGRect)frame {
+  self = [super initWithFrame:frame];
+  if (self) {
+    [self setup];
+  }
+  return self;
+}
+
+- (id)initWithCoder:(NSCoder*)aDecoder {
+  self = [super initWithCoder:aDecoder];
+  if (self) {
+    [self setup];
+  }
+  return self;
+}
+
+- (void)setup {
+  propertyReleaser_NewTabPageBar_.Init(self, [NewTabPageBar class]);
+  self.selectedIndex = NSNotFound;
+  canAnimate_ = NO;
+  self.autoresizingMask =
+      UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleBottomMargin;
+  self.autoresizesSubviews = YES;
+  self.backgroundColor = [UIColor clearColor];
+
+  if ([self showOverlay]) {
+    overlayView_.reset(
+        [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, buttonWidth_, 2)]);
+
+    // Center |overlayColorView_| inside |overlayView_|.
+    CGFloat colorX = AlignValueToPixel((buttonWidth_ - kOverlayColorWidth) / 2);
+    overlayColorView_.reset([[UIView alloc]
+        initWithFrame:CGRectMake(colorX, 0, kOverlayColorWidth, 2)]);
+    [overlayColorView_
+        setBackgroundColor:UIColorFromRGB(kOverlayViewColor, 1.0)];
+    [overlayColorView_ layer].cornerRadius = 1.0;
+    [overlayColorView_
+        setAutoresizingMask:UIViewAutoresizingFlexibleLeftMargin |
+                            UIViewAutoresizingFlexibleRightMargin];
+    [overlayView_ addSubview:overlayColorView_];
+    [self addSubview:overlayView_];
+  }
+
+  // Make the drop shadow.
+  UIImage* shadowImage = [UIImage imageNamed:@"ntp_bottom_bar_shadow"];
+  shadow_.reset([[UIImageView alloc] initWithImage:shadowImage]);
+  // Shadow is positioned directly above the new tab page bar.
+  [shadow_
+      setFrame:CGRectMake(0, -shadowImage.size.height, self.bounds.size.width,
+                          shadowImage.size.height)];
+  [shadow_ setAutoresizingMask:UIViewAutoresizingFlexibleWidth];
+  [self addSubview:shadow_];
+
+  self.contentMode = UIViewContentModeRedraw;
+}
+
+- (void)layoutSubviews {
+  [super layoutSubviews];
+
+  // |buttonWidth_| changes with the screen orientation when the NTP button bar
+  // is enabled.
+  [self calculateButtonWidth];
+
+  CGFloat logoWidth = logoView_.get().image.size.width;
+  CGFloat padding = [self useIconsInButtons] ? logoWidth : 0;
+  CGFloat buttonPadding = floor((CGRectGetWidth(self.bounds) - padding -
+                                 (buttonWidth_ * self.buttons.count) / 2) +
+                                padding);
+
+  for (NSUInteger i = 0; i < self.buttons.count; ++i) {
+    NewTabPageBarButton* button = [self.buttons objectAtIndex:i];
+    LayoutRect layout = LayoutRectMake(
+        buttonPadding + (i * buttonWidth_), CGRectGetWidth(self.bounds), 0,
+        buttonWidth_, CGRectGetHeight(self.bounds));
+    button.frame = LayoutRectGetRect(layout);
+    [button
+        setContentToDisplay:[self useIconsInButtons]
+                                ? new_tab_page_bar_button::ContentType::IMAGE
+                                : new_tab_page_bar_button::ContentType::TEXT];
+  }
+
+  // Position overlay image over percentage of tab bar button(s).
+  CGRect frame = [overlayView_ frame];
+  frame.origin.x = floor(
+      buttonWidth_ * self.buttons.count * overlayPercentage_ + buttonPadding);
+  frame.size.width = buttonWidth_;
+  DCHECK(!std::isnan(frame.origin.x));
+  DCHECK(!std::isnan(frame.size.width));
+  [overlayView_ setFrame:frame];
+}
+
+- (CGSize)sizeThatFits:(CGSize)size {
+  return CGSizeMake(size.width, kBarHeight);
+}
+
+- (void)calculateButtonWidth {
+  if ([self useIconsInButtons]) {
+    if ([items_ count] > 0) {
+      buttonWidth_ = self.bounds.size.width / [items_ count];
+    } else {
+      // In incognito on phones, there are no items shown.
+      buttonWidth_ = 0;
+    }
+    return;
+  }
+
+  buttonWidth_ = kRegularLayoutButtonWidth;
+}
+
+// When setting a new set of items on the tab bar, the buttons need to be
+// regenerated and the old buttons need to be removed.
+- (void)setItems:(NSArray*)newItems {
+  if (newItems == items_)
+    return;
+
+  [items_ autorelease];
+  items_ = [newItems retain];
+  // Remove all the existing buttons from the view.
+  for (UIButton* button in self.buttons) {
+    [button removeFromSuperview];
+  }
+
+  // Create a set of new buttons.
+  [self calculateButtonWidth];
+  if (newItems.count) {
+    NSMutableArray* newButtons = [NSMutableArray array];
+    for (NSUInteger i = 0; i < newItems.count; ++i) {
+      NewTabPageBarItem* item = [newItems objectAtIndex:i];
+      NewTabPageBarButton* button = [NewTabPageBarButton buttonWithItem:item];
+      button.frame = CGRectIntegral(CGRectMake(
+          i * buttonWidth_, 0, buttonWidth_, self.bounds.size.height));
+      [self setupButton:button];
+      [self addSubview:button];
+      [newButtons addObject:button];
+    }
+    self.buttons = newButtons;
+  } else {
+    self.buttons = nil;
+  }
+  [self setNeedsLayout];
+}
+
+- (void)setOverlayPercentage:(CGFloat)overlayPercentage {
+  DCHECK(!std::isnan(overlayPercentage));
+  overlayPercentage_ = overlayPercentage;
+  [self setNeedsLayout];
+}
+
+- (void)setupButton:(UIButton*)button {
+  // Old NTP tab bar buttons have a non-standard control event for firing
+  // actions.  Because they are tied to a scrollView that reacts immediately,
+  // and on phone there is a tooltip that fires on touchdown that needs to
+  // display while on the new tab, the control event for -buttonDidTap is touch
+  // down. On phone with dialogs enabled, treat the NTP buttons as normal
+  // buttons, where the standard is to fire an action on touch up inside.
+  if ([self showOverlay]) {
+    [button addTarget:self
+                  action:@selector(buttonDidTap:)
+        forControlEvents:UIControlEventTouchDown];
+  } else {
+    [button addTarget:self
+                  action:@selector(buttonDidTap:)
+        forControlEvents:UIControlEventTouchUpInside];
+  }
+}
+
+- (void)setSelectedIndex:(NSUInteger)newIndex {
+  // When not showing the overlay, the Bookmarks and Recent Tabs are displayed
+  // in modal view controllers, so the tab bar buttons should not be selected.
+  if (![self showOverlay])
+    return;
+  if (newIndex != self.selectedIndex) {
+    if (newIndex < self.items.count) {
+      for (NSUInteger i = 0; i < self.buttons.count; ++i) {
+        UIButton* button = [self.buttons objectAtIndex:i];
+        button.selected = (i == newIndex);
+      }
+    }
+    selectedIndex_ = newIndex;
+  }
+}
+
+- (void)buttonDidTap:(UIButton*)button {
+  canAnimate_ = YES;
+  NSUInteger buttonIndex = [self.buttons indexOfObject:button];
+  if (buttonIndex != NSNotFound) {
+    self.selectedIndex = buttonIndex;
+    [delegate_ newTabBarItemDidChange:[self.items objectAtIndex:buttonIndex]
+                          changePanel:YES];
+  }
+}
+
+- (void)setShadowAlpha:(CGFloat)alpha {
+  CGFloat currentAlpha = [shadow_ alpha];
+  CGFloat diff = std::abs(alpha - currentAlpha);
+  if (diff >= 1) {
+    [UIView animateWithDuration:0.3
+                     animations:^{
+                       [shadow_ setAlpha:alpha];
+                     }];
+  } else {
+    [shadow_ setAlpha:alpha];
+  }
+}
+
+- (void)updateColorsForScrollView:(UIScrollView*)scrollView {
+  if (![self showOverlay]) {
+    return;
+  }
+
+  UIColor* backgroundViewColorBookmarks = [UIColor whiteColor];
+  CGFloat viewWidth = self.bounds.size.width;
+  CGFloat progress = LeadingContentOffsetForScrollView(scrollView) / viewWidth;
+  progress = fminf(progress, 1.0f);
+  progress = fmaxf(progress, 0.0f);
+
+  if ([self.items count] == kNumberOfTabsIncognito) {
+    UIColor* overlayViewColor = UIColorFromRGB(kOverlayViewColor, 1.0);
+    UIColor* overlayViewColorIncognito = [UIColor whiteColor];
+    UIColor* updatedOverlayColor = InterpolateFromColorToColor(
+        overlayViewColor, overlayViewColorIncognito, progress);
+    [overlayColorView_ setBackgroundColor:updatedOverlayColor];
+
+    UIColor* backgroundViewColorIncognito =
+        [UIColor colorWithWhite:34 / 255.0 alpha:1.0];
+    UIColor* backgroundColor = InterpolateFromColorToColor(
+        backgroundViewColorBookmarks, backgroundViewColorIncognito, progress);
+    self.backgroundColor = backgroundColor;
+    scrollView.backgroundColor = backgroundColor;
+
+    for (NewTabPageBarButton* button in self.buttons) {
+      [button useIncognitoColorScheme:progress];
+    }
+  } else {
+    UIColor* backgroundColor = backgroundViewColorBookmarks;
+    self.backgroundColor = backgroundViewColorBookmarks;
+    scrollView.backgroundColor = backgroundColor;
+  }
+}
+
+- (BOOL)useIconsInButtons {
+  return !IsIPadIdiom() || IsCompactTablet();
+}
+
+- (BOOL)showOverlay {
+  // The bar buttons launch modal dialogs on tap on iPhone. Don't show overlay
+  // in this case.
+  return IsIPadIdiom();
+}
+
+@end