Eclipse Plug-in Developer Guide
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Platform Plug-in Developer Guide Reference Extension Points Reference

Internal and External Editors

Identifier:

org.eclipse.ui.editors

Description:

This extension point is used to add new editors to the workbench. A editor is a visual component within a workbench page. It is typically used to edit or browse a document or input object. To open an editor, the user will typically invoke "Open" on an IFile. When this action is performed the workbench registry is consulted to determine an appropriate editor for the file type and then a new instance of the editor type is created. The actual result depends on the type of the editor. The workbench provides support for the creation of internal editors, which are tightly integrated into the workbench, and external editors, which are launched in a separate frame window. There are also various level of integration between these extremes.

In the case of an internal editor tight integration can be achieved between the workbench window and the editor part. The workbench menu and toolbar are pre-loaded with a number of common actions, such as cut, copy, and paste. The active part, view or editor, is expected to provide the implementation for these actions. An internal editor may also define new actions which appear in the workbench window. These actions only appear when the editor is active.

The integration between the workbench and external editors is more tenuous. In this case the workbench may launch an editor but after has no way of determining the state of the external editor or collaborating with it by any means except through the file system.

Configuration Markup:

<!ELEMENT extension ( editor*)>

<!ATTLIST extension

point CDATA #REQUIRED

id CDATA #IMPLIED

name CDATA #IMPLIED

point - a fully qualified identifier of the target extension point
id - an optional identifier of the extension instance
name - an optional name of the extension instance

<!ELEMENT editor ( contentTypeBinding*)>

<!ATTLIST editor

id CDATA #REQUIRED

name CDATA #REQUIRED

icon CDATA #IMPLIED

extensions CDATA #IMPLIED

class CDATA #IMPLIED

command CDATA #IMPLIED

launcher CDATA #IMPLIED

contributorClass CDATA #IMPLIED

default (true | false) "false"

filenames CDATA #IMPLIED

symbolicFontName CDATA #IMPLIED

matchingStrategy CDATA #IMPLIED

id - a unique name that will be used to identify this editor
name - a translatable name that will be used in the UI for this editor
icon - A relative name of the icon that will be used for all resources that match the specified extensions. Editors should provide an icon to make it easy for users to distinguish between different editor types. If you specify a command rather than a class, an icon is not needed. In that case, the workbench will use the icon provided by the operating system.
extensions - an optional field containing the list of file types understood by the editor. This is a string containing comma separate file extensions. For instance, an editor which understands hypertext documents may register for "htm, html".
class - the name of a class that implements org.eclipse.ui.IEditorPart. The attributes class, command, and launcher are mutually exclusive. If this attribute is defined then contributorClass should also be defined.
command - a command to run in order to launch an external editor. The executable command must be located on the system path or in the plug-in's directory. The attributes class, command, and launcher are mutually exclusive.
launcher - the name of a class which that implements org.eclipse.ui.IEditorLauncher. A launcher will open an external editor. The attributes class, command, and launcher are mutually exclusive.
contributorClass - the name of a class that implements org.eclipse.ui.IEditorActionBarContributor. This attribute should only be defined if the class attribute is defined. This class is used to add new actions to the workbench menu and tool bar which reflect the features of the editor type.
default - if true, this editor will be used as the default editor for the type. This is only relevant in a case where more than one editor is registered for the same type. If an editor is not the default for the type, it can still be launched using "Open with..." submenu for the selected resource.
Please note that this attribute is only honored for filename and extension associations at this time. It will not be honored for content type bindings. Content type-based resolution will occur on a first come, first serve basis and is not explicitly specified.
filenames - an optional field containing the list of file names understood by the editor. This is a string containing comma separate file names. For instance, an editor which understands specific hypertext documents may register for "ejb.htm, ejb.html".
symbolicFontName - the symbolic name of a font. The symbolic font name must be the id of a defined font (see org.eclipse.ui.fontDefinitions). If this attribute is missing or invalid then the font name is the value of "org.eclipse.jface.textfont" in the editor's preferences store. If there is no preference store or the key is not defined then the JFace text font will be used. The editor implementation decides if it uses this symbolic font name to set the font.
matchingStrategy - the name of a class that implements org.eclipse.ui.IEditorMatchingStrategy. This attribute should only be defined if the class attribute is defined. This allows the editor extension to provide its own algorithm for matching the input of one of its editors to a given editor input.

<!ELEMENT contentTypeBinding EMPTY>

<!ATTLIST contentTypeBinding

contentTypeId IDREF #REQUIRED

Advertises that the containing editor understands the given content type and is suitable for editing files of that type.

contentTypeId - The content type identifier. This is an ID defined by the 'org.eclipse.core.contenttype.contentTypes' extension point.

Examples:

The following is an example of an internal editor extension definition:


   <extension point=
"org.eclipse.ui.editors"
> 
      <editor 
         id=
"com.xyz.XMLEditor"
 
         name=
"Fancy XYZ XML editor"
 
         icon=
"./icons/XMLEditor.gif"
 
         extensions=
"xml"
 
         class=
"com.xyz.XMLEditor"
 
         contributorClass=
"com.xyz.XMLEditorContributor"
 
         symbolicFontName=
"org.eclipse.jface.textfont"

         default=
"false"
> 
      </editor> 
   </extension>

Supplied Implementation:

The workbench provides a "Default Text Editor". The end user product may contain other editors as part of the shipping bundle. In that case, editors will be registered as extensions using the syntax described above.

Copyright (c) 2002, 2007 IBM Corporation and others.
All rights reserved. This program and the accompanying materials are made available under the terms of the Eclipse Public License v1.0 which accompanies this distribution, and is available at https://www.eclipse.org/legal/epl-v10.html