1Image(3)              User Contributed Perl Documentation             Image(3)
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NAME

6       Tk::Image - Create and manipulate images
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SYNOPSIS

9       $image = $widget->type(?arg arg ...?)
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11       $image->method(?arg arg ...?)
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DESCRIPTION

14       The image constructors and methods are used to create, delete, and
15       query images.  It can take several different forms, depending on the
16       type.
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18       The constructors require a $widget to invoke them, this is used to
19       locate a MainWindow. (This is because the underlying Tk code registers
20       the images in the data structure for the MainWindow.)
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22       The legal forms are:
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24       $widget->type?(?name?,?option=>value ...)?
25           Creates a new image and returns an object.  type specifies the type
26           of the image, which must be one of the types currently defined
27           (e.g., Bitmap).  name specifies the name for the image;  if it is
28           omitted then Tk picks a name of the form imagex, where x is an
29           integer.  There may be any number of option=>value pairs, which
30           provide configuration options for the new image.  The legal set of
31           options is defined separately for each image type;  see below for
32           details on the options for built-in image types.  If an image
33           already exists by the given name then it is replaced with the new
34           image and any instances of that image will redisplay with the new
35           contents.
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37       $image->delete
38           Deletes the image $image and returns an empty string.  If there are
39           instances of the image displayed in widgets, the image won't
40           actually be deleted until all of the instances are released.
41           However, the association between the instances and the image
42           manager will be dropped.  Existing instances will retain their
43           sizes but redisplay as empty areas.  If a deleted image is
44           recreated (with the same name) the existing instances will use the
45           new image.
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47       $image->height
48           Returns a decimal string giving the height of image name in pixels.
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50       $image->inuse
51           Returns a boolean value indicating whether or not the image is in
52           use by any widgets.
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54       $widget->imageNames
55           Returns a list containing all existing images for $widget's
56           MainWindow.
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58       $image->type
59           Returns the type of  $image (the value of the type method when the
60           image was created).
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62       $widget->imageTypes
63           Returns a list whose elements are all of the valid image types
64           (i.e., all of the values that may be supplied for the type to
65           create an image).
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67       $image->width
68           Returns a decimal string giving the width of image name in pixels.
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BUILT-IN IMAGE TYPES

71       The following image types are defined by Tk so they will be available
72       in any Tk application.  Individual applications or extensions may
73       define additional types.
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75       Bitmap
76           Each pixel in the image displays a foreground color, a background
77           color, or nothing.  See Tk::Bitmap for more information.
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79       Pixmap
80           Pixmap is slightly more general than Bitmap, each pixel can be any
81           available color or "transparent" (rendered as background color of
82           the widget image is displayed in). Pixmap is best used for icons
83           and other simple graphics with only a few colors.
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85           Pixmap is derived from Tix. See Tk::Pixmap for more information.
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87       Photo
88           Displays a variety of full-color images, using dithering to
89           approximate colors on displays with limited color capabilities.
90           See Tk::Photo documentation for more information.
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CAVEATS

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

99       Tk::Bitmap Tk::Pixmap Tk::Photo
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KEYWORDS

102       height, image, types of images, width
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106perl v5.28.0                      2018-07-15                          Image(3)
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