INX widgets and parameters#
This page contains the reference documentation for INX widgets and parameters. Their primary goal is to make it easy to design GUIs for Inkscape Extensions using the built-in INX extension descriptor format, although (invisible) parameters can also be used for extensions that don’t need to show a user interface.
Introduction#
Extension GUIs consists of an arbitrary number of GUI elements, so-called Widgets. These can be simple text labels, boxes and spacers to control layout or more complex UI elements like images.
A special class of Widgets are Parameters. They differ from other Widgets in that they have a user-settable value, for example a boolean (implemented as checkbox) or integer (implemented as number entry). The value of each Parameter is passed to the extension on execution and can be used to control its behavior.
All Widgets are described using an easy-to-learn XML schema with predefined tags and attributes which are described in detail below.
Available Widgets#
A general Widget takes the form
<widget_name attribute1="value1" attribute2="value2" ...>value</widget_name>
where widget_name
specifies the name of the widget and is one of the
following:
label
since 1.0hbox
since 1.0/vbox
since 1.0separator
since 1.0/spacer
since 1.0image
since 1.0param
(for all Parameter types)
Available Parameter types#
A general Parameter takes the form
<param type="parameter_type" attribute1="value1" atribute2="value2" ...>value</param >
where parameter_type
specifies the type of the parameter and is one
of the following:
bool
since 1.0int
float
string
path
since 1.0optiongroup
notebook
color
If a parameter is made invisible (see gui-hidden
attribute in the
next section) it will not be shown in the GUI
but it’s value is still passed to an extension. This is useful if you
want to hardcode parameter value the user should not be able to change.
If all parameters (and potential widgets) are invisible, Inkscape will
not show a GUI and execute the extension immediately instead, but will
still pass the values of the invisible parameters.
Common attributes#
For all widgets#
Attribute name |
Allowed value(s) |
Default value |
Required? |
---|---|---|---|
|
|
|
optional |
If set to Note: If there are no visible parameters defined in a GUI, the extension is executed immediately without showing a dialog. |
|||
|
|
|
optional |
Sets indentation level of the parameter. Increasing indentation adds padding to the start of the line. |
Only for Parameters#
Attribute name |
Allowed value(s) |
Default value |
Required? |
---|---|---|---|
|
(text) |
– |
required |
Used as an identifier of the parameter. It has to be unique since the value of this attribute is used to save and transmit parameter values internally! |
|||
|
see above |
– |
required |
Determines the type of the parameter, see the extensive description of Parameters below. |
|||
|
(text) |
– |
required (visible
parameters), optional
(hidden parameters +
|
Label shown for the parameter in the GUI. |
|||
|
(text) |
– |
optional |
Tooltip shown for the parameter when the user hovers the mouse cursor over the active area of the parameter in question. |
Widgets#
hbox
/ vbox
#
Creates a container for other widgets. No visual rendering but provides a possibility to align and
layout other widgets. Child widgets are either added in horizontal (hbox
) or vertical
(vbox
) direction.
<hbox>…</hbox> <vbox>…</vbox>
A box can contain an arbitrary number of other widgets and parameters (including other boxes) to fine-tune the layout of the GUI.
Note: When you start with an empty extension GUI, you’re basically starting with a vbox
.
Also notebook
pages behave like vertically oriented boxes.
image
#
Creates a widget displaying an image. The content of the node specifies the path of the image file (ideally specify a path relative to the .inx file itself).
<image>path/to/image.svg</image>
By default the image will be rendered at it’s actual size. Use
attributes width/heigth
to override the default size (in this case
both attributes need to be supplied; units are pixels).
Images are aligned in the horizontal center of the current box; different alignment
can be realized by wrapping the image in a hbox and adding a
spacer with size="expand"
before (for right alignment) or after (for left alignment) of the image.
Implementation note: Loadable image formats are determined by GdkPixbuf and therefore system-specific. PNG should always work and is the safe choice. SVG should mostly work and is the preferred choice for obvious reasons.
label
#
Creates a widget showing text. The content of the node corresponds to the text content that will be rendered.
<label>Some text here.</label>
Note: Labels are intended to provide additional information / help. For
labeling parameters use the gui-text
attribute; for short help texts
that are specific to a single parameter prefer gui-description
which
will render as a tooltip.
When setting the attribute
appearance="header"
the text is styled as a heading and can be used as another possibility to group parameters.- When setting the attribute
appearance="url"
the text is rendered as a clickable link.Note: The text is escaped and used as the link target as-is. Creating a link text that differs from the URL is prevented for security reasons. When setting the attribute
xml:space="preserve"
any white-space (spaces, tabs, line-breaks, etc.) in the label will be preserved, allowing to format the label accordingly. By default all leading/tailing and intermediary whitespace is collapsed into a single space character.
separator
#
Creates a separator for visual separation of other widgets. Renders as a horizontal/vertical line.
<separator />
The direction of the separator will automatically adjust depending on
direction of the current container (vertical for “empty” extension GUIs
and notebook
pages; vertical/horizontal for vbox
and hbox
respectively).
spacer
#
Creates a spacer for visual separation of other widgets. No visual rendering but provides variable spacing.
<spacer />
The direction of the spacer will automatically adjust depending on
direction of the current container (vertical for “empty” extension GUIs
and notebook
pages; vertical/horizontal for vbox
and hbox
respectively).
Use the size
attribute to set the spacing in pixels (default:
size="10"
). The special value expand
results in a spacer that
grows dynamically and always uses up as much space as possible (useful
for aligning content).
Parameters#
bool
#
New in version 1.0.
Creates a checkbox to set a boolean value. Allowed values are
true
or false
(default value: true
).
<param name="name" type="bool" gui-text="Some label text">false</param>
color
#
Creates a control to select an RGBA color value. Values should be
given in hexadecimal notation, e.g. 0xff0000ff
for red with full
opacity (default value: 0x000000ff
)
<param name="name" type="color" gui-text="Some label text">0x000000ff</param>
Use appearance="colorbutton"
for a simple button that opens a
simplified color picker. Otherwise a full ColorNotebook will be
rendered.
Changed in version 1.0: Implementation note: colors values are internally treated as 32-bit
unsigned integers (unsigned long). Acceptable default values include
everything the standard library function strtoul
1 understands (since Inkscape 1.0).
Earlier Inkscape version only handled decimal numbers. The value passed
to the extension script will also be a decimal number.
float
#
Creates a input to enter a floating point number. Limit the input
range with the min
and max
attributes; set the number of decimal
places with the precision
attribute. (defaults: min="0"
,
max="10"
and precision="1"
; default value: 0)
<param name="name" type="float" precision="1" min="0" max="100"
gui-text="Float Parameter">1.234</param>
Use the attribute appearance="full"
to create a slider with which
the value can be adjusted dynamically over the full range.
int
#
Creates a textbox input to enter an integer number. Limit the input
range with the min
and max
attributes. (defaults: min="0"
and max="10"
; default value: 0)
<param name="name" type="int" min="1" max="100" gui-text="Integer Parameter">1</param>
Use the attribute appearance="full"
to create a slider with which
the value can be adjusted dynamically over the full range.
notebook
#
Creates a set of pages (aka tab control). The user can switch between individual pages. Each page can contain an arbitrary set of other Widgets and Parameters. Individual pages are created with the element.
The returned value for notebook
parameters is the value of the
name
attribute of the selected . By default the first page is
selected.
Notebooks can be used to show widgets based on an option; that option would be implemented as notebook.
<param name="name" type="notebook">
<page name="page_1" gui-text="First page">
…
</page>
<page name="page_2" gui-text="Second page">
…
</page>
</param>
optiongroup
#
Creates a control that allows to select one option one option from a set of multiple choices. The different choices are created with elements.
The returned value for optiongroup
type parameters is the value
of the value
attribute of the selected . By default the first is
selected.
<param name="name" type="optiongroup" appearance="radio/combo"
gui-text="Some label text">
<option value="1">First option</option>
<option value="2">Second option</option>
</param>
New in version 1.0: Set the attribute appearance="radio"
to render radio buttons
(default). Set the attribute appearance="combo"
to display a
drop-down list instead.
path
#
New in version 1.0.
Creates a control to choose a path. Paths can either be entered manually or by using the file chooser that can be opened using the ellipsis button.
The mode
attribute allows to set behavior of the file chooser (i.e.
if files or folders can be selected, if they need to exist previously
and if multiple selections are possible). The filetypes
attribute
holds a comma-separated list of file extensions and restricts the
selectable file types in file picker mode.
<param type="path" name="varname" gui-text="label" mode="$mode" [filetypes="$filetypes"]/>
Possible values for the mode
attribute:
file
- select a single existing filefiles
- select multiple existing filesfolder
- select a single existing folderfolders
- select multiple existing foldersfile_new
- select a single new file namefile_new
- select a single new folder name
Examples
Files:
Choose a file, with file type restriction (optional):
<param name="my_file" type="path" mode="file" filetypes="png,jpg" gui-text="A file:">my/path/to/file.png</param>
Choose multiple files (file type restriction possible, too):
<param name="my_files" type="path" mode="files" gui-text="Multiple files:">my/path/to/file.png</param>
Create a new file:
<param name="my_new_file" type="path" mode="file_new" filetypes="png" gui-text="A new file:">my/path/to/file.png</param>
Folders:
Choose a folder:
<param name="my_folder" type="path" mode="folder" gui-text="A folder:">my/path/</param>
Choose multiple folders:
<param name="my_folders" type="path" mode="folders" gui-text="Folders:">my/path/</param>
Create a new folder:
<param name="my_new_folder" type="path" mode="folder_new" filetypes="png" gui-text="A new folder:">my/path/</param>
Implementation note: Existence of paths are not checked before passing them to the extension, so extension authors need to implement suitable error handling, especially in case of manual path entry. For multiple selections the individual paths are joined using the pipe character (“|”) and passed to the extension as a single string.
string
#
Creates a input to enter a string. Limit the number of characters
the user is allowed to enter with the max-length
attribute.
(defaults: no character limit; default value: empty string)
<param name="name" type="string" gui-text="Some text label">Some default text</param>
New in version 1.0: Set the attribute appearance="multiline"
to render a multi-line
input. Line-breaks will be encoded as literal \n
in the value passed
to the extension.