91 lines
3.3 KiB
C++
91 lines
3.3 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* 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
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
/* the features that media queries can test */
|
|
|
|
#ifndef nsMediaFeatures_h_
|
|
#define nsMediaFeatures_h_
|
|
|
|
#include "nsCSSProps.h"
|
|
|
|
class nsIAtom;
|
|
class nsPresContext;
|
|
class nsCSSValue;
|
|
|
|
struct nsMediaFeature;
|
|
typedef nsresult
|
|
(* nsMediaFeatureValueGetter)(nsPresContext* aPresContext,
|
|
const nsMediaFeature* aFeature,
|
|
nsCSSValue& aResult);
|
|
|
|
struct nsMediaFeature
|
|
{
|
|
nsIAtom **mName; // extra indirection to point to nsGkAtoms members
|
|
|
|
enum RangeType { eMinMaxAllowed, eMinMaxNotAllowed };
|
|
RangeType mRangeType;
|
|
|
|
enum ValueType {
|
|
// All value types allow eCSSUnit_Null to indicate that no value
|
|
// was given (in addition to the types listed below).
|
|
eLength, // values are such that nsCSSValue::IsLengthUnit() is true
|
|
eInteger, // values are eCSSUnit_Integer
|
|
eFloat, // values are eCSSUnit_Number
|
|
eBoolInteger,// values are eCSSUnit_Integer (0, -0, or 1 only)
|
|
eIntRatio, // values are eCSSUnit_Array of two eCSSUnit_Integer
|
|
eResolution, // values are in eCSSUnit_Inch (for dpi),
|
|
// eCSSUnit_Pixel (for dppx), or
|
|
// eCSSUnit_Centimeter (for dpcm)
|
|
eEnumerated, // values are eCSSUnit_Enumerated (uses keyword table)
|
|
eIdent // values are eCSSUnit_Ident
|
|
// Note that a number of pieces of code (both for parsing and
|
|
// for matching of valueless expressions) assume that all numeric
|
|
// value types cannot be negative. The parsing code also does
|
|
// not allow zeros in eIntRatio types.
|
|
};
|
|
ValueType mValueType;
|
|
|
|
enum RequirementFlags : uint8_t {
|
|
// Bitfield of requirements that must be satisfied in order for this
|
|
// media feature to be active.
|
|
eNoRequirements = 0,
|
|
eHasWebkitPrefix = 1 << 0, // Feature name must start w/ "-webkit-", even
|
|
// before any "min-"/"max-" qualifier.
|
|
|
|
// Feature is only supported if the pref
|
|
// "layout.css.prefixes.device-pixel-ratio-webkit" is enabled.
|
|
// (Should only be used for -webkit-device-pixel-ratio.)
|
|
eWebkitDevicePixelRatioPrefEnabled = 1 << 1
|
|
};
|
|
uint8_t mReqFlags;
|
|
|
|
union {
|
|
// In static arrays, it's the first member that's initialized. We
|
|
// need that to be void* so we can initialize both other types.
|
|
// This member should never be accessed by name.
|
|
const void* mInitializer_;
|
|
// If mValueType == eEnumerated: const int32_t*: keyword table in
|
|
// the same format as the keyword tables in nsCSSProps.
|
|
const nsCSSProps::KTableEntry* mKeywordTable;
|
|
// If mGetter == GetSystemMetric (which implies mValueType ==
|
|
// eBoolInteger): nsIAtom * const *, for the system metric.
|
|
nsIAtom * const * mMetric;
|
|
} mData;
|
|
|
|
// A function that returns the current value for this feature for a
|
|
// given presentation. If it returns eCSSUnit_Null, the feature is
|
|
// not present.
|
|
nsMediaFeatureValueGetter mGetter;
|
|
};
|
|
|
|
class nsMediaFeatures
|
|
{
|
|
public:
|
|
// Terminated with an entry whose mName is null.
|
|
static const nsMediaFeature features[];
|
|
};
|
|
|
|
#endif /* !defined(nsMediaFeatures_h_) */
|