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Writing a plugin

• Most plugins simply add an entry to the Tools menu and register a keyboard shortcut

• However, plugins can access a large API and can add quite a bit of customized behavior.

• Plugins can even run in the background and perform actions in response to OnOpen, OnClose, and OnKey events

Changing an existing plugin

• Let's say we want to change the plugin "Insert accented character"

• Look at files in the SciTE home directory (Windows, this is the directory containing SciTE.exe, Linux, this is /usr/share/scite-with-python or /usr/local/share/scite-with-python)

• From this directory open tools_internal/tools_insert_accented_character/register.properties

• To change the keyboard binding: type a new binding into the line that starts with customcommand.insert_accented_character.shortcut

• To change the code: edit tools_internal/tools_insert_accented_character/__init__.py

• To disable the plugin: delete or rename register.properties

Adding a new plugin

• Look at files in the SciTE home directory (Windows, this is the directory containing SciTE.exe, Linux, this is /usr/share/scite-with-python or /usr/local/share/scite-with-python)

• Create a new directory in the form tools_internal/example

• Create a file register.properties within tools_internal/example

• Let's say we are on Windows and we want the keyboard shortcut Ctrl+Shift+Q to open Notepad

• Add the following to tools_internal/example/register.properties

    *customcommandsregister.example_opennotepad=example_opennotepad|
    customcommand.example_opennotepad.name=Open notepad
    customcommand.example_opennotepad.shortcut=Ctrl+Shift+Q
    customcommand.example_opennotepad.action.start=C:\Windows\System32\notepad.exe

• Open SciTEGlobal.properties and scroll to the end, noticing other import statements. Add the line

    import tools_internal/example/register

• Save changes, close SciTE, and re-open SciTE. Now the item "Open notepad" will appear in the Tools menu, bound to Ctrl+Shift+Q

• If we want the plugin to only be active if a .txt file is open, add this line to tools_internal/example/register.properties

    customcommand.example_opennotepad.filetypes=*.txt

Using variables

• Edit the last line of tools_internal/example/register.properties so that it reads

    customcommand.example_opennotepad.action.start=C:\Windows\System32\notepad.exe "$(FilePath)"

• Now Ctrl+Shift+Q will open the currently opened file in Notepad.

• Other variables exposed include $(CurrentWord), $(CurrentSelection), $(SciteDefaultHome), $(SciteUserHome), and $(FileDir)

Adding a Python plugin

• Let's create a plugin that makes three copies of the current line when the user presses Ctrl+Shift+3

• Follow the steps from "adding a new plugin" above

• Open tools_internal/example/register.properties and add the following registration

    *customcommandsregister.example_makethreecopies=example_makethreecopies|
    customcommand.example_makethreecopies.name=Make three copies
    customcommand.example_makethreecopies.shortcut=Ctrl+Shift+3
    customcommand.example_makethreecopies.action.py=ThisModule().makeThreeCopies()
    customcommand.example_makethreecopies.path=tools_internal/example

• Create a file tools_internal/example/__init__.py.

• Add the following code to tools_internal/example/__init__.py

    def makeThreeCopies():
        from scite_extend_ui import ScEditor
        ScEditor.LineDuplicate()
        ScEditor.LineDuplicate()
        ScEditor.LineDuplicate()

• Save, close SciTE, and re-open SciTE. Type some text into a document. Pressing Ctrl+Shift+3 will run the plugin and make three copies of the current line.

• See other ScEditor methods here.

Registering for events

• Let's create a plugin that inserts the text '456' whenever you type the text '123'

• Follow every step in "adding a Python plugin" above

• Add the following line to tools_internal/example/register.properties, after the line that starts with customcommand.example_makethreecopies.path,

    customcommand.example_makethreecopies.callbacks=OnChar

• Add the following code to tools_internal/example/__init__.py

    def OnChar(c):
        print('OnChar seen, character = ' + chr(c))
        if chr(c) == '3':
            from scite_extend_ui import ScEditor
            current_pos = ScEditor.GetCurrentPos()
            if chr(ScEditor.GetCharAt(current_pos - 2)) == '2':
                if chr(ScEditor.GetCharAt(current_pos - 3)) == '1':
                    ScEditor.ReplaceSel('456')

• Save, close SciTE, and re-open SciTE. After typing a few letters, the output pane on the right should show the "OnChar seen" logging we added. (Logging like this is useful when developing a plugin.)

• After typing '123' into a document, the text '456' should appear

• Events that can be registered: OnOpen, OnBeforeSave, OnSave, OnDoubleClick, OnMarginClick, OnClose, OnChar, OnUserListSelection, OnKey, OnFileChange

• The OnKey method is given four arguments (key, shift, ctrl, alt), where shift, ctrl, and alt are bools

• OnOpen, OnBeforeSave, OnSave, OnClose are given the current filename as an argument

• Register for more than one event by writing customcommand.example_makethreecopies.callbacks=OnChar|OnOpen

Useful API calls

• ScApp.GetFilePath() returns path of current file

• ScEditor.GetSelectedText() returns the selected text

• ScEditor.ReplaceSel(text) to insert text at the current caret position as if the text were typed

• ScEditor.BeginUndoAction() and ScEditor.EndUndoAction(), so that Ctrl+Z will undo a set of changes

• ScEditor.SetSel(start, end) to set the selection

• Note that any method on ScEditor can also be called on ScOutput

• Be sure to see the API reference

User-interfaces

• Multi-key (chained) shortcuts

  • Use ScAskUserChoiceByPressingKey to create a multi-key shortcut

  • It will capture the next keypress and invoke a callback with the choice that was made

  • See it in action by using a built-in plugin like "change casing" or "change lines"

  • As input, provide a list of strings, with each string in the format "key|choice id|string to display"

    class ExampleAskChoice(object):
      def go(self):
          from scite_extend_ui import ScAskUserChoiceByPressingKey
          self.choices = ['M|mint|Mint ice cream',
              'C|chocolate|Chocolate ice cream',
              'P|pecan|Pecan ice cream']
          ScAskUserChoiceByPressingKey(
              choices=self.choices, label='Please choose', callback=self.onChoiceMade)
    
      def onChoiceMade(self, choice):
          print('You chose ' + choice)
    
    def makeThreeCopies():
      from scite_extend_ui import ScEditor
      ScEditor.LineDuplicate()
      ScEditor.LineDuplicate()
      ScEditor.LineDuplicate()
      ExampleAskChoice().go()

• GUI interfaces

  • Use ScToolUIBase to create a user-interface complete with labels, buttons, entry boxes, and combo boxes

  • It will be shown at the bottom of the editor, staying open until the user presses Escape or clicks a button with close action

  • See it in action by pressing Ctrl+Shift+G to start the built-in search-for-filenames tool

  • Make a class deriving from ScToolUIBase, with an AddControls() method and OnOpen() method

    from scite_extend_ui import ScToolUIBase, ScApp
    class ExampleUserInterface(ScToolUIBase):
      def AddControls(self):
          self.AddLabel('Please enter text:')
          self.cmbBox = self.AddCombo()
          self.AddButton('Perform action', callback=self.OnPerformAction, default=True)
          self.AddButton('Close', closes=True)
    
      def OnOpen(self):
          self.Set(self.cmbBox, 'some initial text here')
    
      def OnPerformAction(self):
          textEntered = self.Get(self.cmbBox)
          print('You entered the text ' + textEntered)
          print('The current file is ' + ScApp.GetFilePath())
    
    def RunPlugin():
      ExampleUserInterface().Show()

  • Methods on ScToolUIBase

    • self.Show() creates and displays the UI

    • self.Close() closes the UI

    • self.AddLabel(text) (to only be called within the AddControls method)

    • self.AddButton(text, callback=None, closes=False, default=False) (to only be called within the AddControls method)

    • self.AddCombo() (to only be called within the AddControls method)

    • self.AddEntry(text) (to only be called within the AddControls method)

    • self.AddRow() (to only be called within the AddControls method)

    • self.Get(control) retrieves the current text in an Entry or Combo

    • self.Set(control, text) sets the current text in an Entry or Combo

    • self.SetList(control, text) sets the options in a Combo, provide one string delimited by \n

  • Optionally, override the method def OnEvent(self, control, eventType) and receive events

    • from scite_extend_ui import ScConst

    • values for eventType include ScConst.eventTypeChange, ScConst.eventTypeFocusIn, ScConst.eventTypeFocusOut

• Custom context menus

  • ScEditor.UserListShow and registering for the event OnUserListSelection can be used to show a custom context menu

• Modal dialogs

  • In Windows, ScApp.MsgBox(s) will show a message box

  • In Windows, see the Python module tools_internal/wincommondialog which can show text input dialogs, file open dialogs, file save dialogs, and dialogs asking for confirmation

• Sending data

  • In Windows, other processes can send events to SciTE with a WM_COPYDATA message if they have SciTE's process id. For example, tools_external/tools_search/code_search_definition.py in def sendSciteCmdNavigateToFirstResult; this code is running in an external python.exe process, but it can tell SciTE.exe to open a file.

  • SciTE can be started with command-line arguments to run actions on startup, as described in SciTE Documentation / search for the text "Command line arguments to SciTE"

Registration modes

• When registering a plugin, there are different registration modes

• Use customcommand.example.action.waitforcomplete_console and provide the path to a executable along with optional command-line arguments. The command will be run and standard output will appear in the output pane.

• Use customcommand.example.action.waitforcomplete and provide the path to a executable along with optional command-line arguments.

• Use customcommand.example.action.start and provide the path to a executable along with optional command-line arguments. The process will be run asynchronously in the background, and not waited for.

• Use customcommand.example.action.py and provide Python code to run. Typically uses ThisModule(), see the example above.

• Advanced: use customcommand.example.action.py_immediate and provide Python code to run. The code will run immediately, even if another command is already running.

• Advanced: code running as py_immediate can call ScApp.RequestThatEventContinuesToPropagate(), which raises a special exception telling SciTE to let the keyboard event continue. For a plugin that registers for Ctrl+S and that calls ScApp.RequestThatEventContinuesToPropagate(), when you press Ctrl+S, both the plugin and SciTE's default action "save" occur.

• Further options, for example customcommand.example.mode=filter:yes,quiet:yes,savebefore:yes

  • filter:yes tells SciTE to refresh the current file after running the tool

  • quiet:yes suppresses standard out

  • savebefore:yes will automatically save current document before running tool

  • safebefore:prompt will ask if current document should be saved before running tool