Accelerator scopes

An accelerator scope is used to define the appropriate context for accelerator keys.  The workbench defines two accelerator scopes:

• Global scope means an accelerator is appropriate throughout the workbench UI.
• Text editor scope means the accelerator is only appropriate while a text editor is active.

The scope dictates when an accelerator set (in the active accelerator configuration) is considered active.  The scope is declared in the accelerator set markup:

<extension
      point="org.eclipse.ui.acceleratorSets">
   <acceleratorSet
         scopeId="org.eclipse.ui.globalScope"
         configurationId="org.eclipse.ui.emacsAcceleratorConfiguration">
      <accelerator
            key="Ctrl+F4||Ctrl+X Ctrl+K"
            id="org.eclipse.ui.file.close">
      </accelerator>
      <accelerator
            key="Ctrl+Shift+F4||Ctrl+X Ctrl+C"
            id="org.eclipse.ui.file.closeAll">
      </accelerator>
      <accelerator
            key="Ctrl+X Ctrl+S"
            id="org.eclipse.ui.file.save">
      </accelerator>
      ...

How is the current scope determined?  By default, the workbench operates in a global scope.  When a text editor becomes active, it is responsible for resetting the scope to the text editor scope.  This is all handled by the workbench and text editor code.  Most plug-ins need only determine the appropriate scope for their accelerator sets when defining them.  

Defining new accelerator scopes

When a plug-in defines an accelerator set, it usually assigns it to an existing accelerator scope.   However, if your plug-in defines a new style of editor, it's possible that you'll also want to introduce a new scope for accelerator keys.  For example, a multi-page editor may have different scopes for each page in the editor.  

When you define your own scope, it is up to your plug-in to ensure that the proper scopes are set into the IKeyBindingService as appropriate for your editor.  A complete discussion of how this works is beyond the scope (pun intended!) of this documentation.  Refer to IKeyBindingService and its implementors for more detail.  

Plug-ins define accelerator scopes using the org.eclipse.ui.acceleratorScopes extension point.  The workbench markup for the global and text editor accelerator configurations is shown below:

<extension
    point="org.eclipse.ui.acceleratorScopes">
      <acceleratorScope
            name="%GlobalAcceleratorScope.name"
            description="%GlobalAcceleratorScope.description"
            id="org.eclipse.ui.globalScope">
      </acceleratorScope>
      <acceleratorScope
            name="%TextEditorAcceleratorScope.name"
            parentScope="org.eclipse.ui.globalScope"
            description="%TextEditorAcceleratorScope.description"
            id="org.eclipse.ui.textEditorScope">
      </acceleratorScope>
</extension>