Creating New Functions for Live Templates
The Predefined Functions are the building blocks for creating Parameterized Templates and Surround Templates. However, sometimes the Predefined Functions are not enough.
This tutorial illustrates how to add custom functions to an IntelliJ Platform plugin and make them available for use by Live Templates. As an example, a function is created to convert a selection to Title Case. Refer to the SDK code sample live_templates
.
Implementing a New Function
Under the hood, the predefined functions for Live Templates are called macros. A new custom function for Live Templates is implemented in TitleCaseMacro
, which extends MacroBase
. Three TitleCaseMacro
methods are of particular interest:
The
TitleCaseMacro()
constructor passes the name and description of the macro to the parent constructor.The
isAcceptableInContext()
method tests whether the macro is available in the current context. The test relies on theMarkdownContext
object previously defined in thelive_templates
plugin.The
calculateResult()
method gets invoked when the titleCase function is used in a Live Template. The text to be capitalized is retrieved from the Live Template and converted to Title Case.
Adding a Live Template
Using the procedures previously discussed for Template Creation and Export the Live Template, add a Live Template to the Markdown.xml file for the plugin. The XML representation of an example Live Template using the new titleCase
function is listed below.
There is only one variable, TITLE
. The expression for TITLE
evaluates to the titleCase
function provided by the plugin. The argument to the titleCase
function is SELECTION
, which tells the IntelliJ Platform to operate on the current selection.
Register Extension Point
Using the com.intellij.liveTemplateMacro
extension point, register the implementation with the IntelliJ Platform.
Check Plugin
Now verify the plugin is working correctly.
Run the plugin in a Development Instance.
Create a new file
testing.md
and enter several words in lower case.Highlight the text and enter invoke Surround With popup. Confirm that the SDK: Convert to title case is available in the popup, and select it.
to open theThe selected text will change to have each word capitalized.