GTK+ Reference Manual | ||||
---|---|---|---|---|
#include <gtk/gtk.h> GtkImage; enum GtkImageType; void gtk_image_get_icon_set (GtkImage *image, GtkIconSet **icon_set, GtkIconSize *size); void gtk_image_get_image (GtkImage *image, GdkImage **gdk_image, GdkBitmap **mask); GdkPixbuf* gtk_image_get_pixbuf (GtkImage *image); void gtk_image_get_pixmap (GtkImage *image, GdkPixmap **pixmap, GdkBitmap **mask); void gtk_image_get_stock (GtkImage *image, gchar **stock_id, GtkIconSize *size); GdkPixbufAnimation* gtk_image_get_animation (GtkImage *image); void gtk_image_get_icon_name (GtkImage *image, G_CONST_RETURN gchar **icon_name, GtkIconSize *size); GtkImageType gtk_image_get_storage_type (GtkImage *image); GtkWidget* gtk_image_new_from_file (const gchar *filename); GtkWidget* gtk_image_new_from_icon_set (GtkIconSet *icon_set, GtkIconSize size); GtkWidget* gtk_image_new_from_image (GdkImage *image, GdkBitmap *mask); GtkWidget* gtk_image_new_from_pixbuf (GdkPixbuf *pixbuf); GtkWidget* gtk_image_new_from_pixmap (GdkPixmap *pixmap, GdkBitmap *mask); GtkWidget* gtk_image_new_from_stock (const gchar *stock_id, GtkIconSize size); GtkWidget* gtk_image_new_from_animation (GdkPixbufAnimation *animation); GtkWidget* gtk_image_new_from_icon_name (const gchar *icon_name, GtkIconSize size); void gtk_image_set_from_file (GtkImage *image, const gchar *filename); void gtk_image_set_from_icon_set (GtkImage *image, GtkIconSet *icon_set, GtkIconSize size); void gtk_image_set_from_image (GtkImage *image, GdkImage *gdk_image, GdkBitmap *mask); void gtk_image_set_from_pixbuf (GtkImage *image, GdkPixbuf *pixbuf); void gtk_image_set_from_pixmap (GtkImage *image, GdkPixmap *pixmap, GdkBitmap *mask); void gtk_image_set_from_stock (GtkImage *image, const gchar *stock_id, GtkIconSize size); void gtk_image_set_from_animation (GtkImage *image, GdkPixbufAnimation *animation); void gtk_image_set_from_icon_name (GtkImage *image, const gchar *icon_name, GtkIconSize size); void gtk_image_clear (GtkImage *image); GtkWidget* gtk_image_new (void); void gtk_image_set (GtkImage *image, GdkImage *val, GdkBitmap *mask); void gtk_image_get (GtkImage *image, GdkImage **val, GdkBitmap **mask); void gtk_image_set_pixel_size (GtkImage *image, gint pixel_size); gint gtk_image_get_pixel_size (GtkImage *image);
GObject +----GInitiallyUnowned +----GtkObject +----GtkWidget +----GtkMisc +----GtkImage
"file" gchararray : Read / Write "icon-name" gchararray : Read / Write "icon-set" GtkIconSet : Read / Write "icon-size" gint : Read / Write "image" GdkImage : Read / Write "mask" GdkPixmap : Read / Write "pixbuf" GdkPixbuf : Read / Write "pixbuf-animation" GdkPixbufAnimation : Read / Write "pixel-size" gint : Read / Write "pixmap" GdkPixmap : Read / Write "stock" gchararray : Read / Write "storage-type" GtkImageType : Read
The GtkImage widget displays an image. Various kinds of object
can be displayed as an image; most typically, you would load a
GdkPixbuf ("pixel buffer") from a file, and then display that.
There's a convenience function to do this, gtk_image_new_from_file()
,
used as follows:
GtkWidget *image; image = gtk_image_new_from_file ("myfile.png");
If the file isn't loaded successfully, the image will contain a
"broken image" icon similar to that used in many web browsers.
If you want to handle errors in loading the file yourself,
for example by displaying an error message, then load the image with
gdk_pixbuf_new_from_file()
, then create the GtkImage with
gtk_image_new_from_pixbuf()
.
The image file may contain an animation, if so the GtkImage will display an animation (GdkPixbufAnimation) instead of a static image.
GtkImage is a subclass of GtkMisc, which implies that you can align it (center, left, right) and add padding to it, using GtkMisc methods.
GtkImage is a "no window" widget (has no GdkWindow of its own), so by default does not receive events. If you want to receive events on the image, such as button clicks, place the image inside a GtkEventBox, then connect to the event signals on the event box.
Example 8. Handling button press events on a GtkImage.
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 program
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()
.
typedef struct _GtkImage GtkImage;
This struct contain private data only and should be accessed by the functions below.
typedef enum { GTK_IMAGE_EMPTY, GTK_IMAGE_PIXMAP, GTK_IMAGE_IMAGE, GTK_IMAGE_PIXBUF, GTK_IMAGE_STOCK, GTK_IMAGE_ICON_SET, GTK_IMAGE_ANIMATION, GTK_IMAGE_ICON_NAME } 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.
GTK_IMAGE_EMPTY |
there is no image displayed by the widget |
GTK_IMAGE_PIXMAP |
the widget contains a GdkPixmap |
GTK_IMAGE_IMAGE |
the widget contains a GdkImage |
GTK_IMAGE_PIXBUF |
the widget contains a GdkPixbuf |
GTK_IMAGE_STOCK |
the widget contains a stock icon name (see Stock Items(3)) |
GTK_IMAGE_ICON_SET |
the widget contains a GtkIconSet |
GTK_IMAGE_ANIMATION |
the widget contains a GdkPixbufAnimation |
GTK_IMAGE_ICON_NAME |
the widget contains a named icon. This image type was added in GTK+ 2.6 |
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()
).
image : |
a GtkImage |
icon_set : |
location to store a GtkIconSet |
size : |
location to store a stock icon size |
void gtk_image_get_image (GtkImage *image, GdkImage **gdk_image, GdkBitmap **mask);
Gets the GdkImage and mask being displayed by the GtkImage.
The storage type of the image must be GTK_IMAGE_EMPTY
or
GTK_IMAGE_IMAGE
(see gtk_image_get_storage_type()
).
The caller of this function does not own a reference to the
returned image and mask.
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.
void gtk_image_get_pixmap (GtkImage *image, GdkPixmap **pixmap, GdkBitmap **mask);
Gets the pixmap and mask being displayed by the GtkImage.
The storage type of the image must be GTK_IMAGE_EMPTY
or
GTK_IMAGE_PIXMAP
(see gtk_image_get_storage_type()
).
The caller of this function does not own a reference to the
returned pixmap and mask.
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.
image : |
a GtkImage |
stock_id : |
place to store a stock icon name |
size : |
place to store a stock icon size |
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.
void gtk_image_get_icon_name (GtkImage *image, G_CONST_RETURN 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.
image : |
a GtkImage |
icon_name : |
place to store an icon name |
size : |
place to store an icon size |
Since 2.6
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
.
image : |
a GtkImage |
Returns : | image representation being used |
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.
filename : |
a filename |
Returns : | a new GtkImage |
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.
icon_set : |
a GtkIconSet |
size : |
a stock icon size |
Returns : | a new GtkImage |
GtkWidget* gtk_image_new_from_image (GdkImage *image, GdkBitmap *mask);
Creates a GtkImage widget displaying a image
with a mask
.
A GdkImage is a client-side image buffer in the pixel format of the
current display.
The GtkImage does not assume a reference to the
image or mask; you still need to unref them if you own references.
GtkImage will add its own reference rather than adopting yours.
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_set()
.
GtkWidget* gtk_image_new_from_pixmap (GdkPixmap *pixmap, GdkBitmap *mask);
Creates a GtkImage widget displaying pixmap
with a mask
.
A GdkPixmap is a server-side image buffer in the pixel format of the
current display. The GtkImage does not assume a reference to the
pixmap or mask; you still need to unref them if you own references.
GtkImage will add its own reference rather than adopting yours.
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()
.
stock_id : |
a stock icon name |
size : |
a stock icon size |
Returns : | a new GtkImage displaying the stock icon |
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.
animation : |
an animation |
Returns : | a new GtkImage widget |
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.
icon_name : |
an icon name |
size : |
a stock icon size |
Returns : | a new GtkImage displaying the themed icon |
Since 2.6
void gtk_image_set_from_file (GtkImage *image, const gchar *filename);
See gtk_image_new_from_file()
for details.
void gtk_image_set_from_icon_set (GtkImage *image, GtkIconSet *icon_set, GtkIconSize size);
See gtk_image_new_from_icon_set()
for details.
image : |
a GtkImage |
icon_set : |
a GtkIconSet |
size : |
a stock icon size |
void gtk_image_set_from_image (GtkImage *image, GdkImage *gdk_image, GdkBitmap *mask);
See gtk_image_new_from_image()
for details.
void gtk_image_set_from_pixbuf (GtkImage *image, GdkPixbuf *pixbuf);
See gtk_image_new_from_pixbuf()
for details.
void gtk_image_set_from_pixmap (GtkImage *image, GdkPixmap *pixmap, GdkBitmap *mask);
See gtk_image_new_from_pixmap()
for details.
void gtk_image_set_from_stock (GtkImage *image, const gchar *stock_id, GtkIconSize size);
See gtk_image_new_from_stock()
for details.
image : |
a GtkImage |
stock_id : |
a stock icon name |
size : |
a stock icon size |
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
).
image : |
a GtkImage |
animation : |
the GdkPixbufAnimation |
void gtk_image_set_from_icon_name (GtkImage *image, const gchar *icon_name, GtkIconSize size);
See gtk_image_new_from_icon_name()
for details.
image : |
a GtkImage |
icon_name : |
an icon name |
size : |
an icon size |
Since 2.6
void gtk_image_clear (GtkImage *image);
Resets the image to be empty.
image : |
a GtkImage |
Since 2.8
GtkWidget* gtk_image_new (void);
Creates a new empty GtkImage widget.
Returns : | a newly created GtkImage widget. |
void gtk_image_set (GtkImage *image, GdkImage *val, GdkBitmap *mask);
gtk_image_set
is deprecated and should not be used in newly-written code.
Sets the GtkImage.
void gtk_image_get (GtkImage *image, GdkImage **val, GdkBitmap **mask);
gtk_image_get
is deprecated and should not be used in newly-written code.
Gets the GtkImage.
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()
.
image : |
a GtkImage |
pixel_size : |
the new pixel size |
Since 2.6
file
" property"file" gchararray : Read / Write
Filename to load and display.
Default value: NULL
icon-name
" property"icon-name" gchararray : Read / Write
The name of the icon in the icon theme. If the icon theme is changed, the image will be updated automatically.
Default value: NULL
Since 2.6
icon-size
" property"icon-size" gint : Read / Write
Symbolic size to use for stock icon, icon set or named icon.
Allowed values: >= 0
Default value: 4
pixbuf-animation
" property"pixbuf-animation" GdkPixbufAnimation : Read / Write
GdkPixbufAnimation to display.
pixel-size
" property"pixel-size" gint : Read / Write
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
.
Allowed values: >= -1
Default value: -1
Since 2.6
stock
" property"stock" gchararray : Read / Write
Stock ID for a stock image to display.
Default value: NULL
storage-type
" property"storage-type" GtkImageType : Read
The representation being used for image data.
Default value: GTK_IMAGE_EMPTY