Handling button press events on a GtkImage.

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33

static gboolean
button_press_callback (GtkWidget      *event_box,
                       GdkEventButton *event,
                       gpointer        data)
{
  g_print ("Event box clicked at coordinates %f,%f\n",
           event->x, event->y);

  // Returning TRUE means we handled the event, so the signal
  // emission should be stopped (don’t call any further callbacks
  // that may be connected). Return FALSE to continue invoking callbacks.
  return TRUE;
}

static GtkWidget*
create_image (void)
{
  GtkWidget *image;
  GtkWidget *event_box;

  image = gtk_image_new_from_file ("myfile.png");

  event_box = gtk_event_box_new ();

  gtk_container_add (GTK_CONTAINER (event_box), image);

  g_signal_connect (G_OBJECT (event_box),
                    "button_press_event",
                    G_CALLBACK (button_press_callback),
                    image);

  return image;
}

When handling events on the event box, keep in mind that coordinates in the image may be different from event box coordinates due to the alignment and padding settings on the image (see GtkMisc). The simplest way to solve this is to set the alignment to 0.0 (left/top), and set the padding to zero. Then the origin of the image will be the same as the origin of the event box.

Sometimes an application will want to avoid depending on external data files, such as image files. GTK+ comes with a program to avoid this, called “gdk-pixbuf-csource”. This library allows you to convert an image into a C variable declaration, which can then be loaded into a GdkPixbuf using gdk_pixbuf_new_from_inline().

CSS nodes

GtkImage has a single CSS node with the name image. The style classes may appear on image CSS nodes: .icon-dropshadow, .lowres-icon.

gtk_image_get_icon_set ()

void
gtk_image_get_icon_set (GtkImage *image,
                        GtkIconSet **icon_set,
                        GtkIconSize *size);

Gets the icon set and size being displayed by the GtkImage. The storage type of the image must be GTK_IMAGE_EMPTY or GTK_IMAGE_ICON_SET (see gtk_image_get_storage_type()).

gtk_image_get_pixbuf ()

GdkPixbuf *
gtk_image_get_pixbuf (GtkImage *image);

Gets the GdkPixbuf being displayed by the GtkImage. The storage type of the image must be GTK_IMAGE_EMPTY or GTK_IMAGE_PIXBUF (see gtk_image_get_storage_type()). The caller of this function does not own a reference to the returned pixbuf.

gtk_image_get_stock ()

void
gtk_image_get_stock (GtkImage *image,
                     gchar **stock_id,
                     GtkIconSize *size);

Gets the stock icon name and size being displayed by the GtkImage. The storage type of the image must be GTK_IMAGE_EMPTY or GTK_IMAGE_STOCK (see gtk_image_get_storage_type()). The returned string is owned by the GtkImage and should not be freed.

gtk_image_get_animation ()

GdkPixbufAnimation *
gtk_image_get_animation (GtkImage *image);

Gets the GdkPixbufAnimation being displayed by the GtkImage. The storage type of the image must be GTK_IMAGE_EMPTY or GTK_IMAGE_ANIMATION (see gtk_image_get_storage_type()). The caller of this function does not own a reference to the returned animation.

gtk_image_get_icon_name ()

void
gtk_image_get_icon_name (GtkImage *image,
                         const gchar **icon_name,
                         GtkIconSize *size);

Gets the icon name and size being displayed by the GtkImage. The storage type of the image must be GTK_IMAGE_EMPTY or GTK_IMAGE_ICON_NAME (see gtk_image_get_storage_type()). The returned string is owned by the GtkImage and should not be freed.

Since: 2.6

gtk_image_get_gicon ()

void
gtk_image_get_gicon (GtkImage *image,
                     GIcon **gicon,
                     GtkIconSize *size);

Gets the GIcon and size being displayed by the GtkImage. The storage type of the image must be GTK_IMAGE_EMPTY or GTK_IMAGE_GICON (see gtk_image_get_storage_type()). The caller of this function does not own a reference to the returned GIcon.

Since: 2.14

gtk_image_get_storage_type ()

GtkImageType
gtk_image_get_storage_type (GtkImage *image);

Gets the type of representation being used by the GtkImage to store image data. If the GtkImage has no image data, the return value will be GTK_IMAGE_EMPTY.

gtk_image_new_from_file ()

GtkWidget *
gtk_image_new_from_file (const gchar *filename);

Creates a new GtkImage displaying the file filename . If the file isn’t found or can’t be loaded, the resulting GtkImage will display a “broken image” icon. This function never returns NULL, it always returns a valid GtkImage widget.

If the file contains an animation, the image will contain an animation.

If you need to detect failures to load the file, use gdk_pixbuf_new_from_file() to load the file yourself, then create the GtkImage from the pixbuf. (Or for animations, use gdk_pixbuf_animation_new_from_file()).

The storage type (gtk_image_get_storage_type()) of the returned image is not defined, it will be whatever is appropriate for displaying the file.

gtk_image_new_from_icon_set ()

GtkWidget *
gtk_image_new_from_icon_set (GtkIconSet *icon_set,
                             GtkIconSize size);

Creates a GtkImage displaying an icon set. Sample stock sizes are GTK_ICON_SIZE_MENU, GTK_ICON_SIZE_SMALL_TOOLBAR. Instead of using this function, usually it’s better to create a GtkIconFactory, put your icon sets in the icon factory, add the icon factory to the list of default factories with gtk_icon_factory_add_default(), and then use gtk_image_new_from_stock(). This will allow themes to override the icon you ship with your application.

The GtkImage does not assume a reference to the icon set; you still need to unref it if you own references. GtkImage will add its own reference rather than adopting yours.

gtk_image_new_from_pixbuf ()

GtkWidget *
gtk_image_new_from_pixbuf (GdkPixbuf *pixbuf);

Creates a new GtkImage displaying pixbuf . The GtkImage does not assume a reference to the pixbuf; you still need to unref it if you own references. GtkImage will add its own reference rather than adopting yours.

Note that this function just creates an GtkImage from the pixbuf. The GtkImage created will not react to state changes. Should you want that, you should use gtk_image_new_from_icon_name().

gtk_image_new_from_stock ()

GtkWidget *
gtk_image_new_from_stock (const gchar *stock_id,
                          GtkIconSize size);

Creates a GtkImage displaying a stock icon. Sample stock icon names are GTK_STOCK_OPEN, GTK_STOCK_QUIT. Sample stock sizes are GTK_ICON_SIZE_MENU, GTK_ICON_SIZE_SMALL_TOOLBAR. If the stock icon name isn’t known, the image will be empty. You can register your own stock icon names, see gtk_icon_factory_add_default() and gtk_icon_factory_add().

gtk_image_new_from_animation ()

GtkWidget *
gtk_image_new_from_animation (GdkPixbufAnimation *animation);

Creates a GtkImage displaying the given animation. The GtkImage does not assume a reference to the animation; you still need to unref it if you own references. GtkImage will add its own reference rather than adopting yours.

Note that the animation frames are shown using a timeout with G_PRIORITY_DEFAULT. When using animations to indicate busyness, keep in mind that the animation will only be shown if the main loop is not busy with something that has a higher priority.

gtk_image_new_from_icon_name ()

GtkWidget *
gtk_image_new_from_icon_name (const gchar *icon_name,
                              GtkIconSize size);

Creates a GtkImage displaying an icon from the current icon theme. If the icon name isn’t known, a “broken image” icon will be displayed instead. If the current icon theme is changed, the icon will be updated appropriately.

Since: 2.6

gtk_image_new_from_gicon ()

GtkWidget *
gtk_image_new_from_gicon (GIcon *icon,
                          GtkIconSize size);

Creates a GtkImage displaying an icon from the current icon theme. If the icon name isn’t known, a “broken image” icon will be displayed instead. If the current icon theme is changed, the icon will be updated appropriately.

Since: 2.14

gtk_image_new_from_resource ()

GtkWidget *
gtk_image_new_from_resource (const gchar *resource_path);

Creates a new GtkImage displaying the resource file resource_path . If the file isn’t found or can’t be loaded, the resulting GtkImage will display a “broken image” icon. This function never returns NULL, it always returns a valid GtkImage widget.

If the file contains an animation, the image will contain an animation.

If you need to detect failures to load the file, use gdk_pixbuf_new_from_file() to load the file yourself, then create the GtkImage from the pixbuf. (Or for animations, use gdk_pixbuf_animation_new_from_file()).

The storage type (gtk_image_get_storage_type()) of the returned image is not defined, it will be whatever is appropriate for displaying the file.

Since: 3.4

gtk_image_new_from_surface ()

GtkWidget *
gtk_image_new_from_surface (cairo_surface_t *surface);

Creates a new GtkImage displaying surface . The GtkImage does not assume a reference to the surface; you still need to unref it if you own references. GtkImage will add its own reference rather than adopting yours.

Since: 3.10

gtk_image_set_from_file ()

void
gtk_image_set_from_file (GtkImage *image,
                         const gchar *filename);

See gtk_image_new_from_file() for details.

gtk_image_set_from_icon_set ()

void
gtk_image_set_from_icon_set (GtkImage *image,
                             GtkIconSet *icon_set,
                             GtkIconSize size);

See gtk_image_new_from_icon_set() for details.

gtk_image_set_from_pixbuf ()

void
gtk_image_set_from_pixbuf (GtkImage *image,
                           GdkPixbuf *pixbuf);

See gtk_image_new_from_pixbuf() for details.

gtk_image_set_from_stock ()

void
gtk_image_set_from_stock (GtkImage *image,
                          const gchar *stock_id,
                          GtkIconSize size);

See gtk_image_new_from_stock() for details.

gtk_image_set_from_animation ()

void
gtk_image_set_from_animation (GtkImage *image,
                              GdkPixbufAnimation *animation);

Causes the GtkImage to display the given animation (or display nothing, if you set the animation to NULL).

gtk_image_set_from_icon_name ()

void
gtk_image_set_from_icon_name (GtkImage *image,
                              const gchar *icon_name,
                              GtkIconSize size);

See gtk_image_new_from_icon_name() for details.

Since: 2.6

gtk_image_set_from_gicon ()

void
gtk_image_set_from_gicon (GtkImage *image,
                          GIcon *icon,
                          GtkIconSize size);

See gtk_image_new_from_gicon() for details.

Since: 2.14

gtk_image_set_from_resource ()

void
gtk_image_set_from_resource (GtkImage *image,
                             const gchar *resource_path);

See gtk_image_new_from_resource() for details.

gtk_image_set_from_surface ()

void
gtk_image_set_from_surface (GtkImage *image,
                            cairo_surface_t *surface);

See gtk_image_new_from_surface() for details.

Since: 3.10

gtk_image_clear ()

void
gtk_image_clear (GtkImage *image);

Resets the image to be empty.

Since: 2.8

gtk_image_new ()

GtkWidget *
gtk_image_new (void);

Creates a new empty GtkImage widget.

gtk_image_set_pixel_size ()

void
gtk_image_set_pixel_size (GtkImage *image,
                          gint pixel_size);

Sets the pixel size to use for named icons. If the pixel size is set to a value != -1, it is used instead of the icon size set by gtk_image_set_from_icon_name().

Since: 2.6

gtk_image_get_pixel_size ()

gint
gtk_image_get_pixel_size (GtkImage *image);

Gets the pixel size used for named icons.

Since: 2.6

struct GtkImage

struct GtkImage;

This struct contain private data only and should be accessed by the functions below.

enum GtkImageType

Describes the image data representation used by a GtkImage. If you want to get the image from the widget, you can only get the currently-stored representation. e.g. if the gtk_image_get_storage_type() returns GTK_IMAGE_PIXBUF, then you can call gtk_image_get_pixbuf() but not gtk_image_get_stock(). For empty images, you can request any storage type (call any of the "get" functions), but they will all return NULL values.

The “file” property

  “file”                     char *

Filename to load and display.

Owner: GtkImage

Flags: Read / Write

Default value: NULL

The “gicon” property

  “gicon”                    GIcon *

The GIcon displayed in the GtkImage. For themed icons, If the icon theme is changed, the image will be updated automatically.

Owner: GtkImage

Flags: Read / Write

Since: 2.14

The “icon-name” property

  “icon-name”                char *

The name of the icon in the icon theme. If the icon theme is changed, the image will be updated automatically.

Owner: GtkImage

Flags: Read / Write

Default value: NULL

Since: 2.6

The “icon-set” property

  “icon-set”                 GtkIconSet *

Icon set to display.

Owner: GtkImage

Flags: Read / Write

The “icon-size” property

  “icon-size”                int

Symbolic size to use for stock icon, icon set or named icon.

Owner: GtkImage

Flags: Read / Write

Allowed values: >= 0

Default value: 4

The “pixbuf” property

  “pixbuf”                   GdkPixbuf *

A GdkPixbuf to display.

Owner: GtkImage

Flags: Read / Write

The “pixbuf-animation” property

  “pixbuf-animation”         GdkPixbufAnimation *

GdkPixbufAnimation to display.

Owner: GtkImage

Flags: Read / Write

The “pixel-size” property

  “pixel-size”               int

The "pixel-size" property can be used to specify a fixed size overriding the “icon-size” property for images of type GTK_IMAGE_ICON_NAME.

Owner: GtkImage

Flags: Read / Write

Allowed values: >= -1

Default value: -1

Since: 2.6

The “resource” property

  “resource”                 char *

A path to a resource file to display.

Owner: GtkImage

Flags: Read / Write

Default value: NULL

Since: 3.8

The “stock” property

  “stock”                    char *

Stock ID for a stock image to display.

Owner: GtkImage

Flags: Read / Write

Default value: NULL

The “storage-type” property

  “storage-type”             GtkImageType

The representation being used for image data.

Owner: GtkImage

Flags: Read

Default value: GTK_IMAGE_EMPTY

The “surface” property

  “surface”                  CairoSurface *

A cairo_surface_t to display.

Owner: GtkImage

Flags: Read / Write

The “use-fallback” property

  “use-fallback”             gboolean

Whether the icon displayed in the GtkImage will use standard icon names fallback. The value of this property is only relevant for images of type GTK_IMAGE_ICON_NAME and GTK_IMAGE_GICON.

Owner: GtkImage

Flags: Read / Write

Default value: FALSE

Since: 3.0