QFlags Class

  label->setAlignment(Qt::AlignLeft | Qt::AlignTop);

  class MyClass
  {
  public:
      enum Option {
          NoOptions = 0x0,
          ShowTabs = 0x1,
          ShowAll = 0x2,
          SqueezeBlank = 0x4
      };
      Q_DECLARE_FLAGS(Options, Option)
      ...
  };

  Q_DECLARE_OPERATORS_FOR_FLAGS(MyClass::Options)

  Q_FLAG(Options)

成员函数

QFlags::QFlags(const QFlags &other)

Constructs a copy of other.

QFlags::QFlags(Enum flag)

Constructs a QFlags object storing the given flag.

QFlags::QFlags(Zero zero = Q_NULLPTR)

Constructs a QFlags object with no flags set. zero must be a literal 0 value.

QFlags::QFlags(QFlag value)

Constructs a QFlags object initialized with the given integer value.

The QFlag type is a helper type. By using it here instead of int, we effectively ensure that arbitrary enum values cannot be cast to a QFlags, whereas untyped enum values (i.e., int values) can.

QFlags::QFlags(std::initializer_list<Enum> flags)

Constructs a QFlags object initialized with all flags combined using the bitwise OR operator.

This function was introduced in Qt 5.4.

参见 operator|=() and operator|().

QFlags &QFlags::setFlag(Enum flag, bool on = true)

Sets the indicated flag if on is true or unsets it if on is false. Returns a reference to this object.

This function was introduced in Qt 5.7.

bool QFlags::testFlag(Enum flag) const

Returns true if the flag is set, otherwise false.

This function was introduced in Qt 4.2.

QFlags::operator Int() const

Returns the value stored in the QFlags object as an integer.

参见 Int.

bool QFlags::operator!() const

Returns true if no flag is set (i.e., if the value stored by the QFlags object is 0); otherwise returns false.

QFlags QFlags::operator&(int mask) const

Returns a QFlags object containing the result of the bitwise AND operation on this object and mask.

参见 operator&=(), operator|(), operator^(), and operator~().

QFlags QFlags::operator&(uint mask) const

This is an overloaded function.

QFlags QFlags::operator&(Enum mask) const

This is an overloaded function.

QFlags &QFlags::operator&=(int mask)

Performs a bitwise AND operation with mask and stores the result in this QFlags object. Returns a reference to this object.

参见 operator&(), operator|=(), and operator^=().

QFlags &QFlags::operator&=(uint mask)

This is an overloaded function.

QFlags &QFlags::operator&=(Enum mask)

This is an overloaded function.

QFlags &QFlags::operator=(const QFlags &other)

Assigns other to this object and returns a reference to this object.

QFlags QFlags::operator^(QFlags other) const

Returns a QFlags object containing the result of the bitwise XOR operation on this object and other.

参见 operator^=(), operator&(), operator|(), and operator~().

QFlags QFlags::operator^(Enum other) const

This is an overloaded function.

QFlags &QFlags::operator^=(QFlags other)

Performs a bitwise XOR operation with other and stores the result in this QFlags object. Returns a reference to this object.

参见 operator^(), operator&=(), and operator|=().

QFlags &QFlags::operator^=(Enum other)

This is an overloaded function.

QFlags QFlags::operator|(QFlags other) const

Returns a QFlags object containing the result of the bitwise OR operation on this object and other.

参见 operator|=(), operator^(), operator&(), and operator~().

QFlags QFlags::operator|(Enum other) const

This is an overloaded function.

QFlags &QFlags::operator|=(QFlags other)

Performs a bitwise OR operation with other and stores the result in this QFlags object. Returns a reference to this object.

参见 operator|(), operator&=(), and operator^=().

QFlags &QFlags::operator|=(Enum other)

This is an overloaded function.

QFlags QFlags::operator~() const

Returns a QFlags object that contains the bitwise negation of this object.

参见 operator&(), operator|(), and operator^().

  typedef QFlags<Enum> Flags;