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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/* service providing platform-specific native rendering for widgets */
#ifndef nsITheme_h_
#define nsITheme_h_
#include "mozilla/AlreadyAddRefed.h"
#include "nsISupports.h"
#include "nsID.h"
#include "nscore.h"
#include "Units.h"
struct nsRect;
class gfxContext;
class nsAttrValue;
class nsPresContext;
class nsDeviceContext;
class nsIFrame;
class nsAtom;
class nsIWidget;
namespace mozilla {
class ComputedStyle;
enum class StyleAppearance : uint8_t;
enum class StyleScrollbarWidth : uint8_t;
namespace layers {
class StackingContextHelper;
class RenderRootStateManager;
} // namespace layers
namespace widget {
class Theme;
} // namespace widget
namespace wr {
class DisplayListBuilder;
class IpcResourceUpdateQueue;
} // namespace wr
} // namespace mozilla
// IID for the nsITheme interface
// {7329f760-08cb-450f-8225-dae729096dec}
#define NS_ITHEME_IID \
{ \
0x7329f760, 0x08cb, 0x450f, { \
0x82, 0x25, 0xda, 0xe7, 0x29, 0x09, 0x6d, 0xec \
} \
}
/**
* nsITheme is a service that provides platform-specific native
* rendering for widgets. In other words, it provides the necessary
* operations to draw a rendering object (an nsIFrame) as a native
* widget.
*
* All the methods on nsITheme take a rendering context or device
* context, a frame (the rendering object), and a widget type (one of
* the constants in nsThemeConstants.h).
*/
class nsITheme : public nsISupports {
protected:
using LayoutDeviceIntMargin = mozilla::LayoutDeviceIntMargin;
using LayoutDeviceIntSize = mozilla::LayoutDeviceIntSize;
using LayoutDeviceIntCoord = mozilla::LayoutDeviceIntCoord;
using StyleAppearance = mozilla::StyleAppearance;
using StyleScrollbarWidth = mozilla::StyleScrollbarWidth;
using ComputedStyle = mozilla::ComputedStyle;
public:
NS_DECLARE_STATIC_IID_ACCESSOR(NS_ITHEME_IID)
/**
* Draw the actual theme background.
* @param aContext the context to draw into
* @param aFrame the frame for the widget that we're drawing
* @param aWidgetType the -moz-appearance value to draw
* @param aRect the rectangle defining the area occupied by the widget
* @param aDirtyRect the rectangle that needs to be drawn
* @param DrawOverflow whether outlines, shadows and other such overflowing
* things should be drawn. Honoring this creates better results for
* box-shadow, though it's not a hard requirement.
*/
enum class DrawOverflow { No, Yes };
NS_IMETHOD DrawWidgetBackground(gfxContext* aContext, nsIFrame* aFrame,
StyleAppearance aWidgetType,
const nsRect& aRect, const nsRect& aDirtyRect,
DrawOverflow = DrawOverflow::Yes) = 0;
/**
* Create WebRender commands for the theme background.
* @return true if the theme knows how to create WebRender commands for the
* given widget type, false if DrawWidgetBackground need sto be called
* instead.
*/
virtual bool CreateWebRenderCommandsForWidget(
mozilla::wr::DisplayListBuilder& aBuilder,
mozilla::wr::IpcResourceUpdateQueue& aResources,
const mozilla::layers::StackingContextHelper& aSc,
mozilla::layers::RenderRootStateManager* aManager, nsIFrame* aFrame,
StyleAppearance aWidgetType, const nsRect& aRect) {
return false;
}
/**
* Returns the minimum widths of a scrollbar for a given style, that is, the
* minimum width for a vertical scrollbar, and the minimum height of a
* horizontal scrollbar.
*/
enum class Overlay { No, Yes };
virtual LayoutDeviceIntCoord GetScrollbarSize(const nsPresContext*,
StyleScrollbarWidth,
Overlay) = 0;
/**
* Return the border for the widget, in device pixels.
*/
[[nodiscard]] virtual LayoutDeviceIntMargin GetWidgetBorder(
nsDeviceContext* aContext, nsIFrame* aFrame,
StyleAppearance aWidgetType) = 0;
/**
* This method can return false to indicate that the CSS padding
* value should be used. Otherwise, it will fill in aResult with the
* computed padding, in pixels, and return true.
*
* XXXldb This ought to be required to return true for non-containers
* so that we don't let specified padding that has no effect change
* the computed padding and potentially the size.
*/
virtual bool GetWidgetPadding(nsDeviceContext* aContext, nsIFrame* aFrame,
StyleAppearance aWidgetType,
LayoutDeviceIntMargin* aResult) = 0;
/**
* On entry, *aResult is positioned at 0,0 and sized to the new size
* of aFrame (aFrame->GetSize() may be stale and should not be used).
* This method can return false to indicate that no special
* overflow area is required by the native widget. Otherwise it will
* fill in aResult with the desired overflow area, in appunits, relative
* to the frame origin, and return true.
*
* This overflow area is used to determine what area needs to be
* repainted when the widget changes. However, it does not affect the
* widget's size or what area is reachable by scrollbars. (In other
* words, in layout terms, it affects ink overflow but not
* scrollable overflow.)
*/
virtual bool GetWidgetOverflow(nsDeviceContext* aContext, nsIFrame* aFrame,
StyleAppearance aWidgetType,
/*INOUT*/ nsRect* aOverflowRect) {
return false;
}
/**
* Get the preferred content-box size of a checkbox / radio button, in app
* units. Historically 9px.
*/
virtual nscoord GetCheckboxRadioPrefSize() {
return mozilla::CSSPixel::ToAppUnits(9);
}
/**
* Get the minimum border-box size of a widget, in device pixels.
*/
virtual mozilla::LayoutDeviceIntSize GetMinimumWidgetSize(
nsPresContext* aPresContext, nsIFrame* aFrame,
StyleAppearance aWidgetType) = 0;
enum Transparency { eOpaque = 0, eTransparent, eUnknownTransparency };
/**
* Returns what we know about the transparency of the widget.
*/
virtual Transparency GetWidgetTransparency(nsIFrame* aFrame,
StyleAppearance aWidgetType) {
return eUnknownTransparency;
}
/**
* Sets |*aShouldRepaint| to indicate whether an attribute or content state
* change should trigger a repaint. Call with null |aAttribute| (and
* null |aOldValue|) for content state changes.
*/
NS_IMETHOD WidgetStateChanged(nsIFrame* aFrame, StyleAppearance aWidgetType,
nsAtom* aAttribute, bool* aShouldRepaint,
const nsAttrValue* aOldValue) = 0;
NS_IMETHOD ThemeChanged() = 0;
virtual bool WidgetAppearanceDependsOnWindowFocus(
StyleAppearance aWidgetType) {
return false;
}
/**
* ThemeGeometryType values are used for describing themed nsIFrames in
* calls to nsIWidget::UpdateThemeGeometries. We don't simply pass the
* -moz-appearance value ("widget type") of the frame because the widget may
* want to treat different frames with the same -moz-appearance differently
* based on other properties of the frame. So we give the theme a first look
* at the frame in nsITheme::ThemeGeometryTypeForWidget and pass the
* returned ThemeGeometryType along to the widget.
* Each theme backend defines the ThemeGeometryType values it needs in its
* own nsITheme subclass. eThemeGeometryTypeUnknown is the only value that's
* shared between backends.
*/
typedef uint8_t ThemeGeometryType;
enum { eThemeGeometryTypeUnknown = 0 };
/**
* Returns the theme geometry type that should be used in the ThemeGeometry
* array that's passed to the widget using nsIWidget::UpdateThemeGeometries.
* A return value of eThemeGeometryTypeUnknown means that this frame will
* not be included in the ThemeGeometry array.
*/
virtual ThemeGeometryType ThemeGeometryTypeForWidget(
nsIFrame* aFrame, StyleAppearance aWidgetType) {
return eThemeGeometryTypeUnknown;
}
/**
* Can the nsITheme implementation handle this widget?
*/
virtual bool ThemeSupportsWidget(nsPresContext* aPresContext,
nsIFrame* aFrame,
StyleAppearance aWidgetType) = 0;
virtual bool WidgetIsContainer(StyleAppearance aWidgetType) = 0;
/**
* Does the nsITheme implementation draw its own focus ring for this widget?
*/
virtual bool ThemeDrawsFocusForWidget(nsIFrame*, StyleAppearance) = 0;
// Whether we want an inner focus ring for buttons and menulists.
virtual bool ThemeWantsButtonInnerFocusRing() { return false; }
/**
* Should we insert a dropmarker inside of combobox button?
*/
virtual bool ThemeNeedsComboboxDropmarker() = 0;
virtual bool ThemeSupportsScrollbarButtons() = 0;
};
NS_DEFINE_STATIC_IID_ACCESSOR(nsITheme, NS_ITHEME_IID)
// Singleton accessor functions, these should never return null.
//
// Do not use directly, use nsPresContext::Theme instead.
extern already_AddRefed<nsITheme> do_GetNativeThemeDoNotUseDirectly();
extern already_AddRefed<nsITheme> do_GetBasicNativeThemeDoNotUseDirectly();
extern already_AddRefed<nsITheme> do_GetRDMThemeDoNotUseDirectly();
// Native theme creation function, these should never return null.
extern already_AddRefed<mozilla::widget::Theme>
do_CreateNativeThemeDoNotUseDirectly();
#endif