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 "wtf/PassRefPtr.h"
#include "wtf/RefCounted.h"
#include "wtf/text/WTFString.h"

namespace blink {

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

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

 public:
  virtual ~LayoutTheme() {}

  static LayoutTheme& theme();

  virtual ThemePainter& painter() = 0;

  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& borderBox);

  // 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;

  // Highlight and text colors for TextMatches.
  Color platformTextSearchHighlightColor(bool activeMatch) const;
  Color platformTextSearchColor(bool activeMatch) 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::defaultTapHighlightColor;
  }
  virtual Color platformDefaultCompositionBackgroundColor() const {
    return defaultCompositionBackgroundColor;
  }
  virtual void platformColorsDidChange();

  void setCaretBlinkInterval(double);
  virtual double caretBlinkInterval() const;

  // System fonts and colors for CSS.
  virtual void systemFont(CSSValueID systemFontID,
                          FontStyle&,
                          FontWeight&,
                          float& fontSize,
                          AtomicString& fontFamily) const = 0;
  void systemFont(CSSValueID systemFontID, 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 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 RegularScrollbar;
  }

  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 currentTime,
                                        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 m_platformTheme; }

 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 m_customFocusRingColor;
  bool m_hasCustomFocusRingColor;
  double m_caretBlinkInterval = 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 defaultTapHighlightColor = 0x66000000;

  static const RGBA32 defaultCompositionBackgroundColor = 0xFFFFDD55;

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

}  // namespace blink

#endif  // LayoutTheme_h