widget/LookAndFeel.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef __LookAndFeel
   7 #define __LookAndFeel
   8
   9 #ifndef MOZILLA_INTERNAL_API
  10 #  error "This header is only usable from within libxul (MOZILLA_INTERNAL_API)."
  11 #endif
  12
  13 #include "nsDebug.h"
  14 #include "nsColor.h"
  15 #include "nsString.h"
  16 #include "nsTArray.h"
  17 #include "mozilla/Maybe.h"
  18 #include "mozilla/widget/ThemeChangeKind.h"
  19 #include "mozilla/ColorScheme.h"
  20
  21 struct gfxFontStyle;
  22
  23 class nsIFrame;
  24
  25 namespace mozilla {
  26
  27 using Modifiers = uint16_t;
  28 struct StyleColorSchemeFlags;
  29
  30 namespace dom {
  31 class Document;
  32 }
  33
  34 namespace widget {
  35 class FullLookAndFeel;
  36 }  // namespace widget
  37
  38 enum class StyleSystemColor : uint8_t;
  39 enum class StyleSystemColorScheme : uint8_t;
  40 enum class StyleSystemFont : uint8_t;
  41
  42 class LookAndFeel {
  43  public:
  44   using ColorID = StyleSystemColor;
  45   using ColorScheme = mozilla::ColorScheme;
  46
  47   // When modifying this list, also modify nsXPLookAndFeel::sIntPrefs
  48   // in widget/xpwidgts/nsXPLookAndFeel.cpp.
  49   enum class IntID {
  50     // default, may be overriden by OS
  51     CaretBlinkTime,
  52     // Amount of blinks that happen before the caret stops blinking.
  53     CaretBlinkCount,
  54     // pixel width of caret
  55     CaretWidth,
  56     // select textfields when focused via tab/accesskey?
  57     SelectTextfieldsOnKeyFocus,
  58     // delay before submenus open
  59     SubmenuDelay,
  60     // can popups overlap menu/task bar?
  61     MenusCanOverlapOSBar,
  62     // should overlay scrollbars be used?
  63     UseOverlayScrollbars,
  64     // allow H and V overlay scrollbars to overlap?
  65     AllowOverlayScrollbarsOverlap,
  66     // skip navigating to disabled menu item?
  67     SkipNavigatingDisabledMenuItem,
  68     // begin a drag if the mouse is moved further than the threshold while the
  69     // button is down
  70     DragThresholdX,
  71     DragThresholdY,
  72     // Accessibility theme being used?
  73     UseAccessibilityTheme,
  74
  75     // position of scroll arrows in a scrollbar
  76     ScrollArrowStyle,
  77
  78     // each button can take one of four values:
  79     ScrollButtonLeftMouseButtonAction,
  80     // 0 - scrolls one  line, 1 - scrolls one page
  81     ScrollButtonMiddleMouseButtonAction,
  82     // 2 - scrolls to end, 3 - button ignored
  83     ScrollButtonRightMouseButtonAction,
  84
  85     // delay for opening spring loaded folders
  86     TreeOpenDelay,
  87     // delay for closing spring loaded folders
  88     TreeCloseDelay,
  89     // delay for triggering the tree scrolling
  90     TreeLazyScrollDelay,
  91     // delay for scrolling the tree
  92     TreeScrollDelay,
  93     // the maximum number of lines to be scrolled at ones
  94     TreeScrollLinesMax,
  95     // Should menu items blink when they're chosen?
  96     ChosenMenuItemsShouldBlink,
  97
  98     /*
  99      * A Boolean value to determine whether the Windows accent color
 100      * should be applied to the title bar.
 101      *
 102      * The value of this metric is not used on other platforms. These platforms
 103      * should return NS_ERROR_NOT_IMPLEMENTED when queried for this metric.
 104      */
 105     WindowsAccentColorInTitlebar,
 106
 107     /*
 108      * A Boolean value to determine whether the macOS Big Sur-specific
 109      * theming should be used.
 110      */
 111     MacBigSurTheme,
 112
 113     /*
 114      * A Boolean value to determine whether macOS is in RTL mode or not.
 115      */
 116     MacRTL,
 117
 118     /* Native macOS titlebar height. */
 119     MacTitlebarHeight,
 120
 121     /*
 122      * AlertNotificationOrigin indicates from which corner of the
 123      * screen alerts slide in, and from which direction (horizontal/vertical).
 124      * 0, the default, represents bottom right, sliding vertically.
 125      * Use any bitwise combination of the following constants:
 126      * NS_ALERT_HORIZONTAL (1), NS_ALERT_LEFT (2), NS_ALERT_TOP (4).
 127      *
 128      *       6       4
 129      *     +-----------+
 130      *    7|           |5
 131      *     |           |
 132      *    3|           |1
 133      *     +-----------+
 134      *       2       0
 135      */
 136     AlertNotificationOrigin,
 137
 138     /**
 139      * If true, clicking on a scrollbar (not as in dragging the thumb) defaults
 140      * to scrolling the view corresponding to the clicked point. Otherwise, we
 141      * only do so if the scrollbar is clicked using the middle mouse button or
 142      * if shift is pressed when the scrollbar is clicked.
 143      */
 144     ScrollToClick,
 145
 146     /**
 147      * IME and spell checker underline styles, the values should be
 148      * NS_DECORATION_LINE_STYLE_*.  They are defined below.
 149      */
 150     IMERawInputUnderlineStyle,
 151     IMESelectedRawTextUnderlineStyle,
 152     IMEConvertedTextUnderlineStyle,
 153     IMESelectedConvertedTextUnderline,
 154     SpellCheckerUnderlineStyle,
 155
 156     /**
 157      * If this metric != 0, support window dragging on the menubar.
 158      */
 159     MenuBarDrag,
 160     /**
 161      * 0: scrollbar button repeats to scroll only when cursor is on the button.
 162      * 1: scrollbar button repeats to scroll even if cursor is outside of it.
 163      */
 164     ScrollbarButtonAutoRepeatBehavior,
 165     /*
 166      * A Boolean value to determine whether swipe animations should be used.
 167      */
 168     SwipeAnimationEnabled,
 169
 170     /*
 171      * Controls whether overlay scrollbars display when the user moves
 172      * the mouse in a scrollable frame.
 173      */
 174     ScrollbarDisplayOnMouseMove,
 175
 176     /*
 177      * Overlay scrollbar animation constants.
 178      */
 179     ScrollbarFadeBeginDelay,
 180     ScrollbarFadeDuration,
 181
 182     /**
 183      * Distance in pixels to offset the context menu from the cursor
 184      * on open.
 185      */
 186     ContextMenuOffsetVertical,
 187     ContextMenuOffsetHorizontal,
 188     TooltipOffsetVertical,
 189
 190     /*
 191      * A boolean value indicating whether client-side decorations are
 192      * supported by the user's GTK version.
 193      */
 194     GTKCSDAvailable,
 195
 196     /*
 197      * A boolean value indicating whether semi-transparent
 198      * windows are available.
 199      */
 200     GTKCSDTransparencyAvailable,
 201
 202     /*
 203      * A boolean value indicating whether client-side decorations should
 204      * contain a minimize button.
 205      */
 206     GTKCSDMinimizeButton,
 207
 208     /*
 209      * A boolean value indicating whether client-side decorations should
 210      * contain a maximize button.
 211      */
 212     GTKCSDMaximizeButton,
 213
 214     /*
 215      * A boolean value indicating whether client-side decorations should
 216      * contain a close button.
 217      */
 218     GTKCSDCloseButton,
 219
 220     /**
 221      * An Integer value that will represent the position of the Minimize button
 222      * in GTK Client side decoration header.
 223      */
 224     GTKCSDMinimizeButtonPosition,
 225
 226     /**
 227      * An Integer value that will represent the position of the Maximize button
 228      * in GTK Client side decoration header.
 229      */
 230     GTKCSDMaximizeButtonPosition,
 231
 232     /**
 233      * An Integer value that will represent the position of the Close button
 234      * in GTK Client side decoration header.
 235      */
 236     GTKCSDCloseButtonPosition,
 237
 238     /*
 239      * A boolean value indicating whether titlebar buttons are located
 240      * in left titlebar corner.
 241      */
 242     GTKCSDReversedPlacement,
 243
 244     /*
 245      * A boolean value indicating whether or not the OS is using a dark theme,
 246      * which we may want to switch to as well if not overridden by the user.
 247      */
 248     SystemUsesDarkTheme,
 249
 250     /**
 251      * Corresponding to prefers-reduced-motion.
 252      * https://drafts.csswg.org/mediaqueries-5/#prefers-reduced-motion
 253      * 0: no-preference
 254      * 1: reduce
 255      */
 256     PrefersReducedMotion,
 257
 258     /**
 259      * Corresponding to prefers-reduced-transparency.
 260      * https://drafts.csswg.org/mediaqueries-5/#prefers-reduced-transparency
 261      * 0: no-preference
 262      * 1: reduce
 263      */
 264     PrefersReducedTransparency,
 265
 266     /**
 267      * Corresponding to inverted-colors.
 268      * https://drafts.csswg.org/mediaqueries-5/#inverted
 269      * 0: none
 270      * 1: inverted
 271      */
 272     InvertedColors,
 273
 274     /**
 275      * Corresponding to PointerCapabilities in ServoTypes.h
 276      * 0: None
 277      * 1: Coarse
 278      * 2: Fine
 279      * 4: Hover
 280      */
 281     PrimaryPointerCapabilities,
 282     /**
 283      * Corresponding to union of PointerCapabilities values in ServoTypes.h
 284      * E.g. if there is a mouse and a digitizer, the value will be
 285      * 'Coarse | Fine | Hover'.
 286      */
 287     AllPointerCapabilities,
 288
 289     /** The scrollbar size, in CSS pixels. */
 290     SystemScrollbarSize,
 291
 292     /** A boolean value to determine whether a touch device is present */
 293     TouchDeviceSupportPresent,
 294
 295     /** GTK titlebar radius */
 296     TitlebarRadius,
 297
 298     /** GTK button-to-button spacing in the inline axis */
 299     TitlebarButtonSpacing,
 300
 301     /**
 302      * Corresponding to dynamic-range.
 303      * https://drafts.csswg.org/mediaqueries-5/#dynamic-range
 304      * 0: Standard
 305      * 1: High
 306      */
 307     DynamicRange,
 308
 309     /** Whether XUL panel animations are enabled. */
 310     PanelAnimations,
 311
 312     /* Whether we should hide the cursor while typing */
 313     HideCursorWhileTyping,
 314
 315     /* The StyleGtkThemeFamily of the current GTK theme. */
 316     GTKThemeFamily,
 317
 318     /* Whether macOS' full keyboard access is enabled */
 319     FullKeyboardAccess,
 320
 321     /*
 322      * Not an ID; used to define the range of valid IDs.  Must be last.
 323      */
 324     End,
 325   };
 326
 327   // This is a common enough integer that seems worth the shortcut.
 328   static bool UseOverlayScrollbars() {
 329     return GetInt(IntID::UseOverlayScrollbars);
 330   }
 331
 332   static constexpr int32_t kDefaultTooltipOffset = 21;
 333   static int32_t TooltipOffsetVertical() {
 334     return GetInt(IntID::TooltipOffsetVertical, kDefaultTooltipOffset);
 335   }
 336
 337   // Returns keyCode value of a modifier key which is used for accesskey.
 338   // Returns 0 if the platform doesn't support access key.
 339   static uint32_t GetMenuAccessKey();
 340   // Modifier mask for the menu accesskey.
 341   static Modifiers GetMenuAccessKeyModifiers();
 342
 343   enum {
 344     eScrollArrow_None = 0,
 345     eScrollArrow_StartBackward = 0x1000,
 346     eScrollArrow_StartForward = 0x0100,
 347     eScrollArrow_EndBackward = 0x0010,
 348     eScrollArrow_EndForward = 0x0001
 349   };
 350
 351   enum {
 352     // single arrow at each end
 353     eScrollArrowStyle_Single =
 354         eScrollArrow_StartBackward | eScrollArrow_EndForward,
 355     // both arrows at bottom/right, none at top/left
 356     eScrollArrowStyle_BothAtBottom =
 357         eScrollArrow_EndBackward | eScrollArrow_EndForward,
 358     // both arrows at both ends
 359     eScrollArrowStyle_BothAtEachEnd =
 360         eScrollArrow_EndBackward | eScrollArrow_EndForward |
 361         eScrollArrow_StartBackward | eScrollArrow_StartForward,
 362     // both arrows at top/left, none at bottom/right
 363     eScrollArrowStyle_BothAtTop =
 364         eScrollArrow_StartBackward | eScrollArrow_StartForward
 365   };
 366
 367   // When modifying this list, also modify nsXPLookAndFeel::sFloatPrefs
 368   // in widget/nsXPLookAndFeel.cpp.
 369   enum class FloatID {
 370     IMEUnderlineRelativeSize,
 371     SpellCheckerUnderlineRelativeSize,
 372
 373     // The width/height ratio of the cursor. If used, the CaretWidth int metric
 374     // should be added to the calculated caret width.
 375     CaretAspectRatio,
 376
 377     // GTK text scale factor.
 378     TextScaleFactor,
 379
 380     // Mouse pointer scaling factor.
 381     CursorScale,
 382
 383     // Not an ID; used to define the range of valid IDs.  Must be last.
 384     End,
 385   };
 386
 387   using FontID = mozilla::StyleSystemFont;
 388
 389   static ColorScheme SystemColorScheme() {
 390     return GetInt(IntID::SystemUsesDarkTheme) ? ColorScheme::Dark
 391                                               : ColorScheme::Light;
 392   }
 393
 394   static bool IsDarkColor(nscolor);
 395
 396   static ColorScheme ColorSchemeForStyle(
 397       const dom::Document&, const StyleColorSchemeFlags&,
 398       ColorSchemeMode = ColorSchemeMode::Used);
 399   static ColorScheme ColorSchemeForFrame(
 400       const nsIFrame*, ColorSchemeMode = ColorSchemeMode::Used);
 401
 402   // Whether standins for native colors should be used (that is, colors faked,
 403   // taken from win7, mostly). This forces light appearance, effectively.
 404   enum class UseStandins : bool { No, Yes };
 405   static UseStandins ShouldUseStandins(const dom::Document&, ColorID);
 406
 407   // Returns a native color value (might be overwritten by prefs) for a given
 408   // color id.
 409   //
 410   // NOTE:
 411   //   ColorID::TextSelectForeground might return NS_SAME_AS_FOREGROUND_COLOR.
 412   //   ColorID::IME* might return NS_TRANSPARENT, NS_SAME_AS_FOREGROUND_COLOR or
 413   //   NS_40PERCENT_FOREGROUND_COLOR.
 414   //   These values have particular meaning.  Then, they are not an actual
 415   //   color value.
 416   static Maybe<nscolor> GetColor(ColorID, ColorScheme, UseStandins);
 417
 418   // Gets the color with appropriate defaults for UseStandins, ColorScheme etc
 419   // for a given frame.
 420   static Maybe<nscolor> GetColor(ColorID, const nsIFrame*);
 421
 422   // Versions of the above which returns the color if found, or a default (which
 423   // defaults to opaque black) otherwise.
 424   static nscolor Color(ColorID aId, ColorScheme aScheme,
 425                        UseStandins aUseStandins,
 426                        nscolor aDefault = NS_RGB(0, 0, 0)) {
 427     return GetColor(aId, aScheme, aUseStandins).valueOr(aDefault);
 428   }
 429
 430   static nscolor Color(ColorID aId, nsIFrame* aFrame,
 431                        nscolor aDefault = NS_RGB(0, 0, 0)) {
 432     return GetColor(aId, aFrame).valueOr(aDefault);
 433   }
 434
 435   static float GetTextScaleFactor() {
 436     float f = GetFloat(FloatID::TextScaleFactor, 1.0f);
 437     if (MOZ_UNLIKELY(f <= 0.0f)) {
 438       return 1.0f;
 439     }
 440     return f;
 441   }
 442
 443   struct ZoomSettings {
 444     float mFullZoom = 1.0f;
 445     float mTextZoom = 1.0f;
 446   };
 447
 448   static ZoomSettings SystemZoomSettings();
 449
 450   /**
 451    * GetInt() and GetFloat() return a int or float value for aID.  The result
 452    * might be distance, time, some flags or a int value which has particular
 453    * meaning.  See each document at definition of each ID for the detail.
 454    * The result is always 0 when they return error.  Therefore, if you want to
 455    * use a value for the default value, you should use the other method which
 456    * returns int or float directly.
 457    */
 458   static nsresult GetInt(IntID, int32_t* aResult);
 459   static nsresult GetFloat(FloatID aID, float* aResult);
 460
 461   static int32_t GetInt(IntID aID, int32_t aDefault = 0) {
 462     int32_t result;
 463     if (NS_FAILED(GetInt(aID, &result))) {
 464       return aDefault;
 465     }
 466     return result;
 467   }
 468
 469   static float GetFloat(FloatID aID, float aDefault = 0.0f) {
 470     float result;
 471     if (NS_FAILED(GetFloat(aID, &result))) {
 472       return aDefault;
 473     }
 474     return result;
 475   }
 476
 477   /**
 478    * Retrieve the name and style of a system-theme font.  Returns true
 479    * if the system theme specifies this font, false if a default should
 480    * be used.  In the latter case neither aName nor aStyle is modified.
 481    *
 482    * Size of the font should be in CSS pixels, not device pixels.
 483    *
 484    * @param aID    Which system-theme font is wanted.
 485    * @param aName  The name of the font to use.
 486    * @param aStyle Styling to apply to the font.
 487    */
 488   static bool GetFont(FontID aID, nsString& aName, gfxFontStyle& aStyle);
 489
 490   /**
 491    * GetPasswordCharacter() returns a unicode character which should be used
 492    * for a masked character in password editor.  E.g., '*'.
 493    */
 494   static char16_t GetPasswordCharacter();
 495
 496   /**
 497    * If the latest character in password field shouldn't be hidden by the
 498    * result of GetPasswordCharacter(), GetEchoPassword() returns TRUE.
 499    * Otherwise, FALSE.
 500    */
 501   static bool GetEchoPassword();
 502
 503   /**
 504    * Whether we should be drawing in the titlebar by default.
 505    */
 506   static bool DrawInTitlebar();
 507
 508   enum class TitlebarAction {
 509     None,
 510     WindowLower,
 511     WindowMenu,
 512     WindowMinimize,
 513     WindowMaximize,
 514     WindowMaximizeToggle,
 515     // We don't support more actions (maximize-horizontal, maximize-vertical,..)
 516     // as they're implemented as part of Wayland gtk_surface1 protocol
 517     // which is not accessible to us.
 518   };
 519
 520   enum class TitlebarEvent {
 521     Double_Click,
 522     Middle_Click,
 523   };
 524
 525   /**
 526    * Get system defined action for titlebar events.
 527    */
 528   static TitlebarAction GetTitlebarAction(TitlebarEvent aEvent);
 529
 530   /**
 531    * The millisecond to mask password value.
 532    * This value is only valid when GetEchoPassword() returns true.
 533    */
 534   static uint32_t GetPasswordMaskDelay();
 535
 536   /** Gets theme information for about:support */
 537   static void GetThemeInfo(nsACString&);
 538
 539   /**
 540    * When system look and feel is changed, Refresh() must be called.  Then,
 541    * cached data would be released.
 542    */
 543   static void Refresh();
 544
 545   /**
 546    * GTK's initialization code can't be run off main thread, call this
 547    * if you plan on using LookAndFeel off main thread later.
 548    *
 549    * This initialized state may get reset due to theme changes, so it
 550    * must be called prior to each potential off-main-thread LookAndFeel
 551    * call, not just once.
 552    */
 553   static void NativeInit();
 554
 555   static void SetData(widget::FullLookAndFeel&& aTables);
 556   static void NotifyChangedAllWindows(widget::ThemeChangeKind);
 557   static bool HasPendingGlobalThemeChange() { return sGlobalThemeChanged; }
 558   static void HandleGlobalThemeChange() {
 559     if (MOZ_UNLIKELY(HasPendingGlobalThemeChange())) {
 560       DoHandleGlobalThemeChange();
 561     }
 562   }
 563
 564   static nsresult GetKeyboardLayout(nsACString& aLayout);
 565
 566  protected:
 567   static void DoHandleGlobalThemeChange();
 568   // Set to true when ThemeChanged needs to be called on mTheme (and other
 569   // global LookAndFeel.  This is used because mTheme is a service, so there's
 570   // no need to notify it from more than one prescontext.
 571   static bool sGlobalThemeChanged;
 572 };
 573
 574 }  // namespace mozilla
 575
 576 // ---------------------------------------------------------------------
 577 //  Special colors for ColorID::IME* and ColorID::SpellCheckerUnderline
 578 // ---------------------------------------------------------------------
 579
 580 // For background color only.
 581 constexpr nscolor NS_TRANSPARENT = NS_RGBA(0x01, 0x00, 0x00, 0x00);
 582 // For foreground color only.
 583 constexpr nscolor NS_SAME_AS_FOREGROUND_COLOR = NS_RGBA(0x02, 0x00, 0x00, 0x00);
 584 constexpr nscolor NS_40PERCENT_FOREGROUND_COLOR =
 585     NS_RGBA(0x03, 0x00, 0x00, 0x00);
 586
 587 #define NS_IS_SELECTION_SPECIAL_COLOR(c)                          \
 588   ((c) == NS_TRANSPARENT || (c) == NS_SAME_AS_FOREGROUND_COLOR || \
 589    (c) == NS_40PERCENT_FOREGROUND_COLOR)
 590
 591 // ------------------------------------------
 592 //  Bits for IntID::AlertNotificationOrigin
 593 // ------------------------------------------
 594
 595 #define NS_ALERT_HORIZONTAL 1
 596 #define NS_ALERT_LEFT 2
 597 #define NS_ALERT_TOP 4
 598
 599 #endif /* __LookAndFeel */