Difference between revisions of "Extensions: INX widgets and parameters"

From Inkscape Wiki
Jump to navigation Jump to search
 
(6 intermediate revisions by 4 users not shown)
Line 1: Line 1:
This page contains the reference documentation for INX widgets and parameters. Their primary goal is to make it easy to design GUIs for [[Extension subsystem|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.
{{Template:MovedToOtherSite|topic=Extension development|new_url=https://inkscape.gitlab.io/extensions/documentation/authors/inx-widgets.html|new_site=GitLab}}


== Introduction ==
----
 
Extension GUIs consists of an arbitrary number of GUI elements, so-called '''[[#Widgets|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|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.
 
<!-- TODO: Simple "hello world"-like example -->
 
 
=== Available Widgets ===
 
A general Widget takes the form
 
<source lang="xml">
  <widget_name attribute1="value1" atribute2="value2" …>value</widget_name>
</source>
 
where <code>widget_name</code> specifies the name of the widget and is one of the following:
 
* <code>label</code>{{added_in|1.0}}
* <code>hbox</code>{{added_in|1.0}}/<code>vbox</code>{{added_in|1.0}}
* <code>separator</code>{{added_in|1.0}}/<code>spacer</code>{{added_in|1.0}}
* <code>image</code>{{added_in|1.0}}
* <code>param</code> (for all Parameter types)
 
=== Available Parameter types ===
 
A general Parameter takes the form
 
<source lang="xml">
  <param type="parameter_type" attribute1="value1" atribute2="value2" …>value</param >
</source>
 
where <code>parameter_type</code> specifies the type of the parameter and is one of the following:
 
* <code>bool</code>{{added_in|1.0}}
* <code>int</code>
* <code>float</code>
* <code>string</code>
* <code>path</code>{{added_in|1.0}}
* <code>optiongroup</code>
* <code>notebook</code>
* <code>color</code>
 
If a parameter is made invisible (see <code>gui-hidden</code> attribute in the [[#Common attributes|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 ==
 
{| class="wikitable" style="vertical-align:top;" valign="top"
|-
!colspan="5"|For all Widgets
|-
! Attribute name
! Allowed value(s)
! Default value
! Required?
! Description
|- style="vertical-align:top;"
| style="white-space:nowrap" | <code>gui-hidden</code>
| <code>true</code>,<code>false</code>
| <code>false</code>
| optional
| If set to <code>true</code> the Widget is hidden from the GUI (primarily used to add hidden parameters that are passed to the extension but are not supposed to be editable by the user.)
 
''Note: If there are '''no''' visible parameters defined in a GUI, the extension is executed immediately without showing a dialog.''
|- style="vertical-align:top;"
| style="white-space:nowrap" | <code>indent</code>
| <code>0,1,2,...</code>
| <code>0</code>
| optional
| Sets indentation level of the parameter. Increasing indentation adds padding to the start of the line.
|- style="border:none;background:none"
!colspan="5" style="border:none;background:none"|&nbsp;
|-
!colspan="5"|Only for Parameters
|-
! Attribute name
! Allowed value(s)
! Default value
! Required?
! Description
|- style="vertical-align:top;"
| style="white-space:nowrap" | <code>name</code>
| ''(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!
|- style="vertical-align:top;"
| style="white-space:nowrap" | <code>type</code>
| (see [[#Available Parameter types|above]])
| -
| required
| Determines the type of the parameter, see the extensive description of [[#Parameters|Parameters]] below.
|- style="vertical-align:top;"
| style="white-space:nowrap" | <code>gui-text</code>
| ''(text)''
| -
| required ''(visible parameters)'',<br/>optional ''(hidden parameters + <code>notebook</code>s)''
| Label shown for the parameter in the GUI.
|- style="vertical-align:top;"
| style="white-space:nowrap" | <code>gui-description</code>
| ''(text)''
| -
| optional
| Tooltip shown for the parameter when the user hovers the mouse cursor over the active area of the parameter in question.
|-
|}
 
== Widgets ==
 
{| class="wikitable" style="width:100%"
 
|+ Parameter reference
 
|-
! Type
! Description / Code
! Result
 
|-
! 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 (<code>hbox</code>) or vertical (<code>vbox</code>) direction.
 
<source lang="xml">
<hbox>...</hbox>
<vbox>...</vbox>
</source>
 
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 <code>vbox</code>. Also <code>notebook</code> pages behave like vertically oriented boxes.
 
|
[[File:INX_sample-separators.png]]
 
 
 
|-
! image
|Creates a widget displaying an image. The content of the <code><image></code> node specifies the path of the image file (ideally specify a path relative to the .inx file itself).
 
<source lang="xml">
<image>path/to/image.svg</label>
</source>
 
By default the image will be rendered at it's actual size. Use attributes <code>width/heigth</code> to override the default size (in this case ''both'' attributes need to be supplied; units are pixels).
 
''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.''
 
|
[[File:INX_sample-image.png]]
 
|-
! label
|Creates a widget showing text. The content of the <code><label></code> node corresponds to the text content that will be rendered.
 
<source lang="xml">
<label>Some text here.</label>
</source>
 
''Note: Labels are intended to provide additional information / help. For labeling parameters use the <code>gui-text</code> attribute; for short help texts that are specific to a single parameter prefer <code>gui-description</code> which will render as a tooltip.''
 
* When setting the attribute <code>appearance="header"</code> the text is styled as a heading and can be used as another possibility to group parameters.
* When setting the attribute <code>appearance="url"</code> the text is rendered as a clickable link.<br/>''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 <code>xml:space="preserve"</code> 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.
 
|
[[File:INX_sample-labels.png|frame|none|Different label types (in order):<ul><li>default</li><li><code>appearance="header"</code></li><li><code>appearance="url"</code></li><li><code>xml:space="preserve"</code></li></ul>]]
 
|-
! separator
|Creates a separator for visual separation of other widgets. Renders as a horizontal/vertical line.
 
<source lang="xml">
<separator />
</source>
 
The direction of the separator will automatically adjust depending on direction of the current container (vertical for "empty" extension GUIs and <code>notebook</code> pages; vertical/horizontal for <code>vbox</code> and <code>hbox</code> respectively).
|
[[File:INX_sample-separators.png]]
 
|-
! spacer
|Creates a spacer for visual separation of other widgets. No visual rendering but provides variable spacing.
 
<source lang="xml">
<spacer />
</source>
 
The direction of the spacer will automatically adjust depending on direction of the current container (vertical for "empty" extension GUIs and <code>notebook</code> pages; vertical/horizontal for <code>vbox</code> and <code>hbox</code> respectively).
 
Use the <code>size</code> attribute to set the spacing in pixels (default: <code>size="10"</code>). The special value <code>expand</code> results in a spacer that grows dynamically and always uses up as much space as possible (useful for aligning content).
 
|
[[File:INX_sample-spacers.png|frame|none|Different spacer types:<ol><li>default</li><li><code>size="20"</code></li><li><code>size="expand"</code></li></ol>]]
 
|}
 
== Parameters ==
 
{| class="wikitable" style="width:100%"
 
|+ Parameter reference
 
|-
! Type
! Description / Code
! Result
 
|-
! bool{{added_in|1.0}}
|Creates a checkbox to set a '''boolean value'''. Allowed values are <code>true</code> or <code>false</code> (default value: <code>true</code>).
 
<source lang="xml">
<param name="name" type="boolean" gui-text="Some label text">false</param>
</source>
 
|[[File:INX_sample-boolean.png]]
 
|-
! color
|Creates a control to select an '''RGBA color value'''. Values should be given in hexadecimal notation, e.g. <code>0xff0000ff</code> for red with full opacity (default value: <code>0x000000ff</code>)
 
<source lang="xml">
<param name="name" type="color">0x000000ff</param>
</source>
 
Use <code>appearance="colorbutton"</code> for a simple button that opens a simplified color picker. Otherwise a full ColorNotebook will be rendered.
 
''Implementation note: colors values are internally treated as 32-bit unsigned integers (<code>unsigned long</code>). Acceptable default values include everything the standard library function [https://en.cppreference.com/w/cpp/string/byte/strtoul <code>strtoul</code>] understands{{added_in|1.0}}. Earlier Inkscape version only handled decimal numbers. The value passed to the extension script will also be a decimal number.''
 
|
[[File:INX_sample-color.png|frame|none|default]]
 
[[File:INX color-btn.png|frame|none|<code>appearance="colorbutton"</code>]]
 
|-
! float
|Creates a input to enter a '''floating point number'''. Limit the input range with the <code>min</code> and <code>max</code> attributes; set the number of decimal places with the <code>precision</code> attribute. (defaults: <code>min="0"</code>, <code>max="10"</code> and <code>precision="1"</code>; default value: 0)
 
<source lang="xml">
<param name="name" type="float" precision="3" min="0" max="9999"
gui-text="Some label text">1.234</param>
</source>
 
Use the attribute <code>appearance="full"</code> to create a slider with which the value can be adjusted dynamically over the full range.
 
|
[[File:INX_sample-float.png|frame|none|default]]
 
[[File:INX_sample-float_full.png|frame|none|<code>appearance="full"</code>]]
 
|-
! int
|Creates a textbox input to enter an '''integer number'''. Limit the input range with the <code>min</code> and <code>max</code> attributes. (defaults: <code>min="0"</code> and <code>max="10"</code>; default value: 0)
 
<source lang="xml">
<param name="name" type="int" min="1" max="100" gui-text="Some label text">1</param>
</source>
 
Use the attribute <code>appearance="full"</code> to create a slider with which the value can be adjusted dynamically over the full range.
 
|
[[File:INX_sample-int.png|frame|none|default]]
 
[[File:INX_sample-int_full.png|frame|none|<code>appearance="full"</code>]]
 
|-
! 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 <code><page></code> element.
 
The '''returned value''' for <code>notebook</code> parameters is the value of the <code>name</code> attribute of the selected <code><page></code>. By default the first page is selected.
 
<source lang="xml">
<param name="name" type="notebook">
    <page name="page_1" gui-text="First page">
        ...
    </page>
    <page name="page_2" gui-text="Second page">
        ...
    </page>
</param>
</source>
 
|[[File:INX_sample-notebook.png]]
 
|-
! optiongroup
|Creates a control that allows to select one option '''one option''' from a set of multiple choices. The different choices are created with <code><option></code> elements.
 
The '''returned value''' for <code>optiongroup</code> type parameters is the value of the <code>value</code> attribute of the selected <code><option></code>. By default the first <code><option></code> is selected.
 
<source lang="xml">
<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>
</source>
 
Set the attribute <code>appearance="radio"</code>{{added_in|1.0}} to render radio buttons (default). Set the attribute <code>appearance="combo"</code>{{added_in|1.0}} to display a drop-down list instead.<br>
|
[[File:INX_sample-optiongroup.png|frame|none|<code>appearance="radio"</code>]]
 
[[File:INX_sample-optiongroup-minimal.png|frame|none|<code>appearance="combo"</code>]]
 
|-
! path{{added_in|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 <code>mode</code> 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 <code>filetypes</code> attribute holds a comma-separated list of file extensions and restricts the selectable file types in file picker mode.
 
<source lang="xml">
<param type="path" name="varname" gui-text="label" mode="$mode" [filetypes="$filetypes"]/>
</source>
 
Possible values for the <code>mode</code> attribute:
* <code>file</code> - select a single existing file
* <code>files</code> - select multiple existing files
* <code>folder</code> - select a single existing folder
* <code>folders</code> - select multiple existing folders
* <code>file_new</code> - select a single new file name
* <code>file_new</code> - select a single new folder name
 
''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.''
 
|[[File:INX path.png]]
 
|-
! string
|Creates a input to enter a '''string'''. Limit the number of characters the user is allowed to enter with the <code>max-length</code> attribute. (defaults: no character limit; default value: empty string)
 
<source lang="xml">
<param name="name" type="string" gui-text="Some text label">Some default text</param>
</source>
 
Set the attribute <code>appearance="multiline"</code>{{added_in|1.0}} to render a multi-line input. Line-breaks will be encoded as literal <code>\n</code> in the value passed to the extension.
 
|
[[File:INX_sample-string.png|frame|none|default]]
 
[[File:INX_sample-multiline-string.png|frame|none|<code>appearance="multiline"</code>]]
 
|}
 
== Translation of widgets and parameters ==
 
<!-- TODO -->
 
 
== Deprecated Functionality ==
 
These widgets and parameters have been deprecated and should not be used anymore. Extension authors are encouraged to update their existing extensions wherever possible. Documentation is kept for authors that need to make their extensions backwards-compatible but please be aware that deprecated functionality '''''will''''' be removed eventually and without further notice.
 
{| class="wikitable" style="width:100%"
 
|+ Deprecated Parameters
 
|-
! Type
! Description / Code
! Result
 
|-
! boolean{{deprecated_in|1.0}}
|'''Replace with <code><param type="bool" .../></code> parameter.'''
 
Creates a checkbox to set a '''boolean value'''. Allowed values are <code>true</code> or <code>false</code> (default value: <code>true</code>).
 
<source lang="xml">
<param name="name" type="boolean" gui-text="Some label text">false</param>
</source>
 
|[[File:INX_sample-boolean.png]]
 
|-
! description{{deprecated_in|1.0}}
|'''Replace with <code><label>...</label></code> widget.'''
 
Creates a text element. Specifying the attribute <code>xml:space="preserve"</code> preserves whitespace in the text content  of the description and enables multiline text.
 
<source lang="xml">
<param name="name" type="description">Some text here.</param>
</source>
 
When additionally setting the attribute <code>appearance="header"</code> the text is styled as a heading and can be used as another possibility to group parameters.
<source lang="xml"><param name="name" type="description" appearance="header">Header</param></source>
 
All <code>description</code> type parameters are purely informational (they do not return any value). They are intended to be used to provide additional information / help on other parameters (Consider using the <code>gui-description</code> attribute for short help texts that are specific to a single parameter, though).
 
 
|[[File:INX_sample-description.png]]<br><small>default appearance</small><br><br><br><br>
[[File:INX_sample-description_header.png]]<br><small>with <code>appearance="header"</code></small><br><br><br>&nbsp;
 
 
|-
! enum{{deprecated_in|1.0}}
|'''Replace with <code><optiongroup appearance="combo" ...></code> parameter.'''
 
Creates a drop-down list from which '''one predefined value''' can be chosen. The different choices are created with <code><item></code> elements. The first <code><item></code> is selected by default.
The '''returned value''' for <code>enum</code> type parameters is the value of the <code>value</code> attribute of the selected <code><item></code>.
 
<source lang="xml">
<param name="name" type="enum" gui-text="Some label text">
  <item value="1">First option</item>
  <item value="2">Second option</item>
</param>
</source>
|[[File:INX_sample-enum.png]]
 
|}
 
=== Other deprecations ===
 
* Parameters of type <code>optiongroup</code>:
:* <code>appearance="minimal"</code>{{deprecated_in|1.0}}
 
=== Deprecated localization functionality of parameters{{deprecated_in|1.0}} ===
 
To mark parameters to be included into the translation files variants of all relevant attributes and tag names existed that started with an underscore.
 
While the underscored variants are still accepted for backwards-compatibility, translations are handled differently since Inkscape 1.0, which solved a number of limitations of the prior implementation, while also making the INX specification significantly cleaner. See [[Translation of widgets and parameters]] for details.
 
<!-- TODO
 
Use parameter elements to capture user input for further use by a script. The basic structure of the element is:
 
<source lang="xml">
<param name="some_name" type="some_type">default value</param>
</source>
 
The default value is the value that is shown in the input control the first time the user opens the dialog window. Inkscape automatically displays the values used last time when the dialog window is opened again.
 
 
* Parameter values (when opening the dialog) are set to the last used value, which is saved in the user's preferences file (e.g. ~/.config/inkscape/preferences.xml on GNU/Linux systems):
<source lang="xml">
<inkscape>
  <group id="extensions" com.attrib.id.param_name="param value"/>
</inkscape>
</source>
The (default) values in the inx file are visible only when the user first uses the extension.
 
 
-->


[[Category:Developer Documentation]]
[[Category:Developer Documentation]]
[[Category:Extensions]]
[[Category:Extensions]]

Latest revision as of 19:55, 3 February 2023

The Inkscape Wiki is no longer used to host information about Extension development.

You can now find related information at GitLab.

This page is kept for historical reasons, e.g. to document specific decisions in Inkscape development.

Retrieved from "https://wiki.inkscape.org/wiki/index.php?title=Extensions:_INX_widgets_and_parameters&oldid=122085"