Ubuntu Manpage: Tk::Image - Create and manipulate images

Provided by: perl-tk_804.036+dfsg1-1ubuntu3_amd64

NAME

       Tk::Image - Create and manipulate images

SYNOPSIS

       $image = $widget->type(?arg arg ...?)

       $image->method(?arg arg ...?)

DESCRIPTION

The image constructors and methods are used to create, delete, and query images. It can take several
different forms, depending on the type.

The constructors require a $widget to invoke them, this is used to locate a MainWindow. (This is because
the underlying Tk code registers the images in the data structure for the MainWindow.)

The legal forms are:

$widget->type?(?name?,?option=>value ...)?
Creates a new image and returns an object. type specifies the type of the image, which must be one
of the types currently defined (e.g., Bitmap). name specifies the name for the image; if it is
omitted then Tk picks a name of the form imagex, where x is an integer. There may be any number of
option=>value pairs, which provide configuration options for the new image. The legal set of options
is defined separately for each image type; see below for details on the options for built-in image
types. If an image already exists by the given name then it is replaced with the new image and any
instances of that image will redisplay with the new contents.

$image->delete
Deletes the image $image and returns an empty string. If there are instances of the image displayed
in widgets, the image won't actually be deleted until all of the instances are released. However,
the association between the instances and the image manager will be dropped. Existing instances will
retain their sizes but redisplay as empty areas. If a deleted image is recreated (with the same
name) the existing instances will use the new image.

$image->height
Returns a decimal string giving the height of image name in pixels.

$image->inuse
Returns a boolean value indicating whether or not the image is in use by any widgets.

$widget->imageNames
Returns a list containing all existing images for $widget's MainWindow.

$image->type
Returns the type of $image (the value of the type method when the image was created).

$widget->imageTypes
Returns a list whose elements are all of the valid image types (i.e., all of the values that may be
supplied for the type to create an image).

$image->width
Returns a decimal string giving the width of image name in pixels.

BUILT-IN IMAGE TYPES

       The following image types are defined by Tk so they will be available in any Tk application.   Individual
       applications or extensions may define additional types.

       Bitmap
           Each  pixel in the image displays a foreground color, a background color, or nothing.  See Tk::Bitmap
           for more information.

       Pixmap
           Pixmap is slightly more general than Bitmap, each pixel can be any available color  or  "transparent"
           (rendered as background color of the widget image is displayed in). Pixmap is best used for icons and
           other simple graphics with only a few colors.

           Pixmap is derived from Tix. See Tk::Pixmap for more information.

       Photo
           Displays  a  variety  of  full-color  images,  using dithering to approximate colors on displays with
           limited color capabilities.  See Tk::Photo documentation for more information.

CAVEATS

       It's necessary to use the "delete" method to delete an image object and free memory associated  with  it.
       Just using a lexical variable for storing the image object and letting the variable to go out of scope or
       setting to "undef" is not sufficient.

KEYWORDS