Gdk::DrawingContext Class Reference

Drawing context for GDK windows. More...

`#include <gdkmm/drawingcontext.h>`

Inheritance diagram for Gdk::DrawingContext:
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## Public Member Functions

| DrawingContext (DrawingContext && src) noexcept
DrawingContext & | operator= (DrawingContext && src) noexcept
| ~DrawingContext () noexcept override
GdkDrawingContext * | gobj ()
| Provides access to the underlying C GObject.
const GdkDrawingContext * | gobj () const
| Provides access to the underlying C GObject.
GdkDrawingContext * | gobj_copy ()
| Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.
Glib::RefPtr< Window > | get_window ()
| Retrieves the window that created the drawing context.
Glib::RefPtr< const Window > | get_window () const
| Retrieves the window that created the drawing context.
::Cairo::RefPtr< ::Cairo::Region > | get_clip () const
| Retrieves a copy of the clip region used when creating the context.
bool | is_valid () const
| Checks whether the given Gdk::DrawingContext is valid.
::Cairo::RefPtr< ::Cairo::Context > | get_cairo_context ()
| Retrieves a Cairo context to be used to draw on the Gdk::Window that created the Gdk::DrawingContext.
::Cairo::RefPtr< const ::Cairo::Context > | get_cairo_context () const
| Retrieves a Cairo context to be used to draw on the Gdk::Window that created the Gdk::DrawingContext.
Glib::PropertyProxy_ReadOnly< Glib::RefPtr< Window > > | property_window () const
| The Gdk::Window that created the drawing context.

## Static Public Member Functions

static GType | get_type ()
| Get the GType for this class, for use with the underlying GObject type system.
static Glib::RefPtr< DrawingContext > | get_drawing_context_from_cairo_context (const ::Cairo::RefPtr< ::Cairo::Context > & cr)
| Retrieves the Gdk::DrawingContext that created the Cairo context cr.

## Protected Member Functions

| DrawingContext ()

## Related Symbols

(Note that these are not member symbols.)
Glib::RefPtr< Gdk::DrawingContext > | wrap (GdkDrawingContext * object, bool take_copy=false)
| A Glib::wrap() method for this object.

## Detailed Description

Drawing context for GDK windows.

Gdk::DrawingContext is an object that represents the current drawing state of a Gdk::Window.

It's possible to use a Gdk::DrawingContext to draw on a Gdk::Window via rendering API like Cairo or OpenGL.

A Gdk::DrawingContext can only be created by calling Gdk::Window::begin_draw_frame() and will be valid until a call to Gdk::Window::end_draw_frame().

Since gtkmm 3.22:

## Constructor & Destructor Documentation

## DrawingContext() [1/2]

Gdk::DrawingContext::DrawingContext | ( | DrawingContext && | src | ) |

noexcept

## ~DrawingContext()

Gdk::DrawingContext::~DrawingContext | ( |  | ) |

override noexcept

## DrawingContext() [2/2]

Gdk::DrawingContext::DrawingContext | ( |  | ) |

protected

## Member Function Documentation

## get_cairo_context() [1/2]

::Cairo::RefPtr< ::Cairo::Context > Gdk::DrawingContext::get_cairo_context | ( |  | ) |

Retrieves a Cairo context to be used to draw on the Gdk::Window that created the Gdk::DrawingContext.

The returned context is guaranteed to be valid as long as the Gdk::DrawingContext is valid, that is between a call to Gdk::Window::begin_draw_frame() and Gdk::Window::end_draw_frame().

Since gtkmm 3.22:

Returns
  A Cairo context to be used to draw the contents of the Gdk::Window. The context is owned by the Gdk::DrawingContext and should not be destroyed.

## get_cairo_context() [2/2]

::Cairo::RefPtr< const ::Cairo::Context > Gdk::DrawingContext::get_cairo_context | ( |  | ) | const

Retrieves a Cairo context to be used to draw on the Gdk::Window that created the Gdk::DrawingContext.

The returned context is guaranteed to be valid as long as the Gdk::DrawingContext is valid, that is between a call to Gdk::Window::begin_draw_frame() and Gdk::Window::end_draw_frame().

Since gtkmm 3.22:

Returns
  A Cairo context to be used to draw the contents of the Gdk::Window. The context is owned by the Gdk::DrawingContext and should not be destroyed.

## get_clip()

::Cairo::RefPtr< ::Cairo::Region > Gdk::DrawingContext::get_clip | ( |  | ) | const

Retrieves a copy of the clip region used when creating the context.

Since gtkmm 3.22:

Returns
  A Cairo region.

## get_drawing_context_from_cairo_context()

static Glib::RefPtr< DrawingContext > Gdk::DrawingContext::get_drawing_context_from_cairo_context | ( | const ::Cairo::RefPtr< ::Cairo::Context > & | cr | ) |

static

Retrieves the Gdk::DrawingContext that created the Cairo context cr.

Since gtkmm 3.22:

Parameters

  cr | A Cairo context.

Returns
  A Gdk::DrawingContext, if any is set.

## get_type()

static GType Gdk::DrawingContext::get_type | ( |  | ) |

static

Get the GType for this class, for use with the underlying GObject type system.

## get_window() [1/2]

Glib::RefPtr< Window > Gdk::DrawingContext::get_window | ( |  | ) |

Retrieves the window that created the drawing context.

Since gtkmm 3.22:

Returns
  A Gdk::Window.

## get_window() [2/2]

Glib::RefPtr< const Window > Gdk::DrawingContext::get_window | ( |  | ) | const

Retrieves the window that created the drawing context.

Since gtkmm 3.22:

Returns
  A Gdk::Window.

## gobj() [1/2]

GdkDrawingContext * Gdk::DrawingContext::gobj | ( |  | ) |

inline

Provides access to the underlying C GObject.

## gobj() [2/2]

const GdkDrawingContext * Gdk::DrawingContext::gobj | ( |  | ) | const

inline

Provides access to the underlying C GObject.

## gobj_copy()

GdkDrawingContext * Gdk::DrawingContext::gobj_copy | ( |  | ) |

Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

## is_valid()

bool Gdk::DrawingContext::is_valid | ( |  | ) | const

Checks whether the given Gdk::DrawingContext is valid.

Since gtkmm 3.22:

Returns
  `true` if the context is valid.

## operator=()

DrawingContext & Gdk::DrawingContext::operator= | ( | DrawingContext && | src | ) |

noexcept

## property_window()

Glib::PropertyProxy_ReadOnly< Glib::RefPtr< Window > > Gdk::DrawingContext::property_window | ( |  | ) | const

The Gdk::Window that created the drawing context.

Since gtkmm 3.22:

Returns
  A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.

## Friends And Related Symbol Documentation

## wrap()

Glib::RefPtr< Gdk::DrawingContext > wrap | ( | GdkDrawingContext * | object,
|  | bool | take_copy = `false`
| ) |  |

related

A Glib::wrap() method for this object.

Parameters

  object | The C instance.
  take_copy | False if the result should take ownership of the C instance. True if it should take a new copy or ref.

Returns
  A C++ instance that wraps this C instance.