third_party/WebKit/Source/core/layout/LayoutTheme.h

/*
 * This file is part of the theme implementation for form controls in WebCore.
 *
 * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Computer, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

#ifndef LayoutTheme_h
#define LayoutTheme_h

#include "core/CSSValueKeywords.h"
#include "core/CoreExport.h"
#include "platform/ThemeTypes.h"
#include "platform/fonts/Font.h"
#include "platform/fonts/FontDescription.h"
#include "platform/fonts/FontTraits.h"
#include "platform/graphics/Color.h"
#include "platform/scroll/ScrollTypes.h"
#include "platform/text/PlatformLocale.h"
#include "platform/wtf/PassRefPtr.h"
#include "platform/wtf/RefCounted.h"
#include "platform/wtf/text/WTFString.h"

namespace blink {

class ComputedStyle;
class Element;
class FileList;
class HTMLInputElement;
class LayoutObject;
class PlatformChromeClient;
class Theme;
class ThemePainter;

class CORE_EXPORT LayoutTheme : public RefCounted<LayoutTheme> {
 protected:
  explicit LayoutTheme(Theme*);

 public:
  virtual ~LayoutTheme() {}

  static LayoutTheme& GetTheme();

  virtual ThemePainter& Painter() = 0;

  // This function is called after associated WebThemeEngine instance
  // was replaced. This is called only in tests.
  virtual void DidChangeThemeEngine() {}

  static void SetSizeIfAuto(ComputedStyle&, const IntSize&);

  // This method is called whenever style has been computed for an element and
  // the appearance property has been set to a value other than "none".
  // The theme should map in all of the appropriate metrics and defaults given
  // the contents of the style. This includes sophisticated operations like
  // selection of control size based off the font, the disabling of appearance
  // when certain other properties like "border" are set, or if the appearance
  // is not supported by the theme.
  void AdjustStyle(ComputedStyle&, Element*);

  // The remaining methods should be implemented by the platform-specific
  // portion of the theme, e.g., LayoutThemeMac.cpp for Mac OS X.

  // These methods return the theme's extra style sheets rules, to let each
  // platform adjust the default CSS rules in html.css, quirks.css or
  // mediaControls.css.
  virtual String ExtraDefaultStyleSheet();
  virtual String ExtraQuirksStyleSheet() { return String(); }
  virtual String ExtraMediaControlsStyleSheet() { return String(); }
  virtual String ExtraFullscreenStyleSheet() { return String(); }

  // A method to obtain the baseline position for a "leaf" control. This will
  // only be used if a baseline position cannot be determined by examining child
  // content. Checkboxes and radio buttons are examples of controls that need to
  // do this.
  virtual int BaselinePosition(const LayoutObject*) const;

  // A method for asking if a control is a container or not.  Leaf controls have
  // to have some special behavior (like the baseline position API above).
  bool IsControlContainer(ControlPart) const;

  // Whether or not the control has been styled enough by the author to disable
  // the native appearance.
  virtual bool IsControlStyled(const ComputedStyle&) const;

  // Some controls may spill out of their containers (e.g., the check on an OSX
  // 10.9 checkbox). Add this "visual overflow" to the object's border box rect.
  virtual void AddVisualOverflow(const LayoutObject&, IntRect& border_box);

  // This method is called whenever a control state changes on a particular
  // themed object, e.g., the mouse becomes pressed or a control becomes
  // disabled. The ControlState parameter indicates which state has changed
  // (from having to not having, or vice versa).
  bool ControlStateChanged(LayoutObject&, ControlState) const;

  bool ShouldDrawDefaultFocusRing(const LayoutObject&) const;

  // A method asking if the theme's controls actually care about redrawing when
  // hovered.
  virtual bool SupportsHover(const ComputedStyle&) const { return false; }

  // A method asking if the platform is able to show a calendar picker for a
  // given input type.
  virtual bool SupportsCalendarPicker(const AtomicString&) const;

  // Text selection colors.
  Color ActiveSelectionBackgroundColor() const;
  Color InactiveSelectionBackgroundColor() const;
  Color ActiveSelectionForegroundColor() const;
  Color InactiveSelectionForegroundColor() const;

  // List box selection colors
  Color ActiveListBoxSelectionBackgroundColor() const;
  Color ActiveListBoxSelectionForegroundColor() const;
  Color InactiveListBoxSelectionBackgroundColor() const;
  Color InactiveListBoxSelectionForegroundColor() const;

  virtual Color PlatformSpellingMarkerUnderlineColor() const;
  virtual Color PlatformGrammarMarkerUnderlineColor() const;

  Color PlatformActiveSpellingMarkerHighlightColor() const;

  // Highlight and text colors for TextMatches.
  Color PlatformTextSearchHighlightColor(bool active_match) const;
  Color PlatformTextSearchColor(bool active_match) const;

  Color FocusRingColor() const;
  virtual Color PlatformFocusRingColor() const { return Color(0, 0, 0); }
  void SetCustomFocusRingColor(const Color&);
  static Color TapHighlightColor();
  virtual Color PlatformTapHighlightColor() const {
    return LayoutTheme::kDefaultTapHighlightColor;
  }
  virtual Color PlatformDefaultCompositionBackgroundColor() const {
    return kDefaultCompositionBackgroundColor;
  }
  virtual void PlatformColorsDidChange();

  void SetCaretBlinkInterval(double);
  virtual double CaretBlinkInterval() const;

  // System fonts and colors for CSS.
  virtual void SystemFont(CSSValueID system_font_id,
                          FontStyle&,
                          FontWeight&,
                          float& font_size,
                          AtomicString& font_family) const = 0;
  void SystemFont(CSSValueID system_font_id, FontDescription&);
  virtual Color SystemColor(CSSValueID) const;

  // Whether the default system font should have its average character width
  // adjusted to match MS Shell Dlg.
  virtual bool NeedsHackForTextControlWithFontFamily(
      const AtomicString&) const {
    return false;
  }

  virtual int MinimumMenuListSize(const ComputedStyle&) const { return 0; }

  virtual void AdjustSliderThumbSize(ComputedStyle&) const;

  virtual int PopupInternalPaddingStart(const ComputedStyle&) const {
    return 0;
  }
  virtual int PopupInternalPaddingEnd(const PlatformChromeClient*,
                                      const ComputedStyle&) const {
    return 0;
  }
  virtual int PopupInternalPaddingTop(const ComputedStyle&) const { return 0; }
  virtual int PopupInternalPaddingBottom(const ComputedStyle&) const {
    return 0;
  }

  virtual ScrollbarControlSize ScrollbarControlSizeForPart(ControlPart) {
    return kRegularScrollbar;
  }

  virtual void AdjustProgressBarBounds(ComputedStyle& style) const {}

  // Returns the repeat interval of the animation for the progress bar.
  virtual double AnimationRepeatIntervalForProgressBar() const;
  // Returns the duration of the animation for the progress bar.
  virtual double AnimationDurationForProgressBar() const;

  // Media controls
  String FormatMediaControlsTime(float time) const;
  String FormatMediaControlsCurrentTime(float current_time,
                                        float duration) const;

  // Returns size of one slider tick mark for a horizontal track.
  // For vertical tracks we rotate it and use it. i.e. Width is always length
  // along the track.
  virtual IntSize SliderTickSize() const = 0;
  // Returns the distance of slider tick origin from the slider track center.
  virtual int SliderTickOffsetFromTrackCenter() const = 0;

  virtual bool ShouldHaveSpinButton(HTMLInputElement*) const;

  // Functions for <select> elements.
  virtual bool DelegatesMenuListRendering() const { return false; }
  virtual bool PopsMenuByArrowKeys() const { return false; }
  virtual bool PopsMenuBySpaceKey() const { return false; }
  virtual bool PopsMenuByReturnKey() const { return false; }
  virtual bool PopsMenuByAltDownUpOrF4Key() const { return false; }

  virtual String FileListNameForWidth(Locale&,
                                      const FileList*,
                                      const Font&,
                                      int width) const;

  virtual bool ShouldOpenPickerWithF4Key() const;

  virtual bool SupportsSelectionForegroundColors() const { return true; }

  virtual bool IsModalColorChooser() const { return true; }

  virtual bool ShouldUseFallbackTheme(const ComputedStyle&) const;

 protected:
  // The platform selection color.
  virtual Color PlatformActiveSelectionBackgroundColor() const;
  virtual Color PlatformInactiveSelectionBackgroundColor() const;
  virtual Color PlatformActiveSelectionForegroundColor() const;
  virtual Color PlatformInactiveSelectionForegroundColor() const;

  virtual Color PlatformActiveListBoxSelectionBackgroundColor() const;
  virtual Color PlatformInactiveListBoxSelectionBackgroundColor() const;
  virtual Color PlatformActiveListBoxSelectionForegroundColor() const;
  virtual Color PlatformInactiveListBoxSelectionForegroundColor() const;

  virtual bool ThemeDrawsFocusRing(const ComputedStyle&) const = 0;

  // Methods for each appearance value.
  virtual void AdjustCheckboxStyle(ComputedStyle&) const;
  virtual void SetCheckboxSize(ComputedStyle&) const {}

  virtual void AdjustRadioStyle(ComputedStyle&) const;
  virtual void SetRadioSize(ComputedStyle&) const {}

  virtual void AdjustButtonStyle(ComputedStyle&) const;
  virtual void AdjustInnerSpinButtonStyle(ComputedStyle&) const;

  virtual void AdjustMenuListStyle(ComputedStyle&, Element*) const;
  virtual void AdjustMenuListButtonStyle(ComputedStyle&, Element*) const;
  virtual void AdjustSliderContainerStyle(ComputedStyle&, Element*) const;
  virtual void AdjustSliderThumbStyle(ComputedStyle&) const;
  virtual void AdjustSearchFieldStyle(ComputedStyle&) const;
  virtual void AdjustSearchFieldCancelButtonStyle(ComputedStyle&) const;
  void AdjustStyleUsingFallbackTheme(ComputedStyle&);
  void AdjustCheckboxStyleUsingFallbackTheme(ComputedStyle&) const;
  void AdjustRadioStyleUsingFallbackTheme(ComputedStyle&) const;

  bool HasPlatformTheme() const { return platform_theme_; }

 public:
  // Methods for state querying
  static ControlStates ControlStatesForLayoutObject(const LayoutObject&);
  static bool IsActive(const LayoutObject&);
  static bool IsChecked(const LayoutObject&);
  static bool IsIndeterminate(const LayoutObject&);
  static bool IsEnabled(const LayoutObject&);
  static bool IsFocused(const LayoutObject&);
  static bool IsPressed(const LayoutObject&);
  static bool IsSpinUpButtonPartPressed(const LayoutObject&);
  static bool IsHovered(const LayoutObject&);
  static bool IsSpinUpButtonPartHovered(const LayoutObject&);
  static bool IsReadOnlyControl(const LayoutObject&);

 private:
  // This function is to be implemented in your platform-specific theme
  // implementation to hand back the appropriate platform theme.
  static LayoutTheme& NativeTheme();

  Color custom_focus_ring_color_;
  bool has_custom_focus_ring_color_;
  double caret_blink_interval_ = 0.5;

  // This color is expected to be drawn on a semi-transparent overlay,
  // making it more transparent than its alpha value indicates.
  static const RGBA32 kDefaultTapHighlightColor = 0x66000000;

  static const RGBA32 kDefaultCompositionBackgroundColor = 0xFFFFDD55;

  Theme* platform_theme_;  // The platform-specific theme.
};

}  // namespace blink

#endif  // LayoutTheme_h