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

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

+// Copyright 2015 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_button.h"
+
+#include "base/logging.h"
+#include "base/mac/objc_property_releaser.h"
+#import "ios/chrome/browser/ui/ntp/new_tab_page_bar_item.h"
+#import "ios/chrome/browser/ui/uikit_ui_util.h"
+#import "ios/third_party/material_components_ios/src/components/Typography/src/MaterialTypography.h"
+
+namespace {
+
+const int kButtonColor = 0x333333;
+const int kButtonSelectedColor = 0x4285F4;
+
+}  // anonymous namespace
+
+@interface NewTabPageBarButton () {
+  UIColor* _color;
+  UIColor* _selectedColor;
+  UIColor* _incognitoColor;
+  UIColor* _incognitoSelectedColor;
+  UIColor* _interpolatedColor;
+  UIColor* _interpolatedSelectedColor;
+
+  UIImage* _image;
+  NSString* _title;
+  base::mac::ObjCPropertyReleaser _propertyReleaser_NewTabPageBarButton;
+}
+
+@property(nonatomic, retain) UIColor* color;
+@property(nonatomic, retain) UIColor* selectedColor;
+@property(nonatomic, retain) UIColor* incognitoColor;
+@property(nonatomic, retain) UIColor* incognitoSelectedColor;
+@property(nonatomic, retain) UIColor* interpolatedColor;
+@property(nonatomic, retain) UIColor* interpolatedSelectedColor;
+@property(nonatomic, retain) UIImage* image;
+@property(nonatomic, copy) NSString* title;
+
+// Sets the tint color of the button to |interpolatedColor| or
+// |interpolatedSelectedColor|, depending on the state of the button.
+- (void)refreshTintColor;
+
+@end
+
+@implementation NewTabPageBarButton
+
+@synthesize color = _color;
+@synthesize selectedColor = _selectedColor;
+@synthesize incognitoColor = _incognitoColor;
+@synthesize incognitoSelectedColor = _incognitoSelectedColor;
+@synthesize interpolatedColor = _interpolatedColor;
+@synthesize interpolatedSelectedColor = _interpolatedSelectedColor;
+@synthesize image = _image;
+@synthesize title = _title;
+
++ (instancetype)buttonWithItem:(NewTabPageBarItem*)item {
+  DCHECK(item);
+  DCHECK(item.title);
+  DCHECK(item.image);
+  NewTabPageBarButton* button =
+      [[self class] buttonWithType:UIButtonTypeCustom];
+  button->_propertyReleaser_NewTabPageBarButton.Init(
+      button, [NewTabPageBarButton class]);
+
+  button.title = item.title;
+  button.image =
+      [item.image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
+  button.color = UIColorFromRGB(kButtonColor, 1.0);
+  button.selectedColor = UIColorFromRGB(kButtonSelectedColor, 1.0);
+  button.incognitoColor = [UIColor colorWithWhite:1 alpha:0.5];
+  button.incognitoSelectedColor = [UIColor whiteColor];
+
+  button.autoresizingMask = UIViewAutoresizingFlexibleWidth;
+  button.adjustsImageWhenHighlighted = NO;
+  button.accessibilityLabel = item.title;
+  button.titleLabel.font = [MDCTypography body2Font];
+  button.titleLabel.adjustsFontSizeToFitWidth = YES;
+  button.titleLabel.minimumScaleFactor = 0.6;
+
+  [button useIncognitoColorScheme:0];
+  [button setContentToDisplay:new_tab_page_bar_button::ContentType::TEXT];
+  return button;
+}
+
+- (void)useIncognitoColorScheme:(CGFloat)percentage {
+  DCHECK(percentage >= 0 && percentage <= 1);
+  self.interpolatedColor =
+      InterpolateFromColorToColor(_color, _incognitoColor, percentage);
+  self.interpolatedSelectedColor = InterpolateFromColorToColor(
+      _selectedColor, _incognitoSelectedColor, percentage);
+
+  [self setTitleColor:_interpolatedColor forState:UIControlStateNormal];
+  [self setTitleColor:_interpolatedSelectedColor
+             forState:UIControlStateSelected];
+  [self setTitleColor:_interpolatedSelectedColor
+             forState:UIControlStateHighlighted];
+
+  [self refreshTintColor];
+}
+
+- (void)setContentToDisplay:(new_tab_page_bar_button::ContentType)contentType {
+  switch (contentType) {
+    case new_tab_page_bar_button::ContentType::IMAGE:
+      [self setImage:_image forState:UIControlStateNormal];
+      [self setTitle:nil forState:UIControlStateNormal];
+      break;
+    case new_tab_page_bar_button::ContentType::TEXT:
+      [self setImage:nil forState:UIControlStateNormal];
+      [self setTitle:_title forState:UIControlStateNormal];
+      break;
+  }
+}
+
+- (void)refreshTintColor {
+  if (self.selected || self.highlighted) {
+    [self setTintColor:_interpolatedSelectedColor];
+  } else {
+    [self setTintColor:_interpolatedColor];
+  }
+}
+
+#pragma mark -
+#pragma mark UIButton overrides
+
+- (void)setSelected:(BOOL)selected {
+  [super setSelected:selected];
+  [self refreshTintColor];
+}
+
+- (void)setHighlighted:(BOOL)highlighted {
+  [super setHighlighted:highlighted];
+  [self refreshTintColor];
+}
+
+@end