#
View Menus,Toolbars and Actions

###### Identifier:

org.eclipse.ui.viewActions

###### Description:

This extension point is used to add actions to the pulldown menu and toolbar for views registered by other plug-ins. Each view has a local pulldown menu normally activated by clicking on the top right triangle button. Other plug-ins can contribute submenus and actions to this menu. Plug-ins may also contribute actions to a view toolbar. View owners are first given a chance to populate these areas. Optional additions by other plug-ins are appended.

An action's enablement and/or visibility can be defined using the elements `enablement` and `visibility` respectively. These two elements contain a boolean expression that is evaluated to determine the enablement and/or visibility.

The syntax is the same for the `enablement` and `visibility` elements. Both contain only one boolean expression sub-element. In the simplest case, this will be an `objectClass`, `objectState`, `pluginState`, or `systemProperty` element. In the more complex case, the `and`, `or`, and `not` elements can be combined to form a boolean expression. Both the `and`, and `or` elements must contain 2 sub-elements. The `not` element must contain only 1 sub-element.

###### Configuration Markup:

<!ELEMENT extension (viewContribution+)>

<!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 viewContribution (menu* , action*)>

<!ATTLIST viewContribution

id CDATA #REQUIRED

targetID CDATA #REQUIRED>

This element is used to define a group of view actions and/or menus.

- id - a unique identifier used to reference this contribution.
- targetID - a unique identifier of a registered view that is the target of this contribution.

<!ELEMENT action (selection* | enablement?)>

<!ATTLIST action

id CDATA #REQUIRED

label CDATA #REQUIRED

menubarPath CDATA #IMPLIED

toolbarPath CDATA #IMPLIED

icon CDATA #IMPLIED

disabledIcon CDATA #IMPLIED

hoverIcon CDATA #IMPLIED

tooltip CDATA #IMPLIED

helpContextId CDATA #IMPLIED

style (push|radio|toggle) "push"

state (true | false)

class CDATA #REQUIRED

enablesFor CDATA #IMPLIED>

This element defines an action that the user can invoke in the UI.

- id - a unique identifier used as a reference for this action.
- label - a translatable name used either as the menu item text or toolbar button label. The name can include mnenomic information.
- menubarPath - a slash-delimited path ('/') used to specify the location of this action in the pulldown menu. Each token in the path, except the last one, must represent a valid identifier of an existing menu in the hierarchy. The last token represents the named group into which this action will be added. If the path is omitted, this action will not appear in the pulldown menu.
- toolbarPath - a named group within the local toolbar of the target view. If the group does not exist, it will be created. If omitted, the action will not appear in the local toolbar.
- icon - a relative path of an icon used to visually represent the action in its context. If omitted and the action appears in the toolbar, the Workbench will use a placeholder icon. The path is relative to the location of the plugin.xml file of the contributing plug-in. The icon will appear in the toolbar but not in the pulldown menu.
- disabledIcon - a relative path of an icon used to visually represent the action in its context when the action is disabled. If omitted, the normal icon will simply appear greyed out. The path is relative to the location of the plugin.xml file of the contributing plug-in. The disabled icon will appear in the toolbar but not in the pulldown menu.
- hoverIcon - a relative path of an icon used to visually represent the action in its context when the mouse pointer is over the action. If omitted, the normal icon will be used. The path is relative to the location of the plugin.xml file of the contributing plug-in.
- tooltip - a translatable text representing the action's tool tip. Only used if the action appears in the toolbar.
- helpContextId - a unique identifier indicating the help context for this action. If the action appears as a menu item, then pressing F1 while the menu item is highlighted will display help.
- style - an optional attribute to define the user interface style type for the action. If defined, the attribute value will be one of the following:

  | push | - as a regular menu item or tool item.
  | radio | - as a radio style menu item or tool item. Actions with the radio style within the same menu or toolbar group behave as a radio set. The initial value is specified by the `state` attribute.
  | toggle | - as a checked style menu item or as a toggle tool item. The initial value is specified by the `state` attribute.

- state - an optional attribute indicating the initial state (either `true` or `false`), used when the `style` attribute has the value `radio` or `toggle`.
- class - name of the fully qualified class that implements `org.eclipse.ui.IViewActionDelegate`.
- enablesFor - a value indicating the selection count which must be met to enable the action. If this attribute is specified and the condition is met, the action is enabled. If the condition is not met, the action is disabled. If no attribute is specified, the action is enabled for any number of items selected. The following attribute formats are supported:

  | ! | - 0 items selected
  | ? | - 0 or 1 items selected
  | + | - 1 or more items selected
  | multiple, 2+ | - 2 or more items selected
  | n | - a precise number of items selected.a precise number of items selected. For example: enablesFor=" 4" enables the action only when 4 items are selected
  | * | - any number of items selected

<!ELEMENT menu (separator+ , groupMarker*)>

<!ATTLIST menu

id CDATA #REQUIRED

label CDATA #REQUIRED

path CDATA #IMPLIED>

This element is used to defined a new menu.

- id - a unique identifier that can be used to reference this menu.
- label - a translatable name used by the Workbench for this new menu. The name should include mnemonic information.
- path - the location of the new menu starting from the root of the menu. Each token in the path must refer to an existing menu, except the last token which should represent a named group in the last menu in the path. If omitted, the new menu will be added to the `additions` named group of the menu.

<!ELEMENT separator EMPTY>

<!ATTLIST separator

name CDATA #REQUIRED>

This element is used to create a menu separator in the new menu.

- name - the name of the menu separator. This name can later be referenced as the last token in a menu path. Therefore, a separator also serve as named group into which actions and menus can be added.

<!ELEMENT groupMarker EMPTY>

<!ATTLIST groupMarker

name CDATA #REQUIRED>

This element is used to create a named group in the new menu. It has no visual representation in the new menu, unlike the `separator` element.

- name - the name of the group marker. This name can later be referenced as the last token in the menu path. It serves as named group into which actions and menus can be added.

<!ELEMENT selection EMPTY>

<!ATTLIST selection

class CDATA #REQUIRED

name CDATA #IMPLIED>

This element is used to help determine the action enablement based on the current selection. Ignored if the `enablement` element is specified.

- class - a fully qualified name of the class or interface that each object in the selection must implement in order to enable the action.
- name - an optional wild card filter for the name that can be applied to all objects in the selection. If specified and the match fails, the action will be disabled.

<!ELEMENT enablement (and | or | not | objectClass | objectState | pluginState | systemProperty)>

This element is used to define the enablement for the extension.

<!ELEMENT visibility (and | or | not | objectClass | objectState | pluginState | systemProperty)>

This element is used to define the visibility for the extension.

<!ELEMENT and (and | or | not | objectClass | objectState | pluginState | systemProperty)>

This element represent a boolean AND operation on the result of evaluating it's two sub-element expressions.

<!ELEMENT or (and | or | not | objectClass | objectState | pluginState | systemProperty)>

This element represent a boolean OR operation on the result of evaluating it's two sub-element expressions.

<!ELEMENT not (and | or | not | objectClass | objectState | pluginState | systemProperty)>

This element represent a boolean NOT operation on the result of evaluating it's sub-element expressions.

<!ELEMENT objectClass EMPTY>

<!ATTLIST objectClass

name CDATA #REQUIRED>

This element is used to evaluate the class or interface of each object in the current selection. If each object in the selection implements the specified class or interface, the expression is evaluated as true.

- name - a fully qualified name of a class or interface. The expression is evaluated as true only if all objects within the selection implement this class or interface.

<!ELEMENT objectState EMPTY>

<!ATTLIST objectState

name CDATA #REQUIRED

value CDATA #REQUIRED>

This element is used to evaluate the attribute state of each object in the current selection. If each object in the selection has the specified attribute state, the expression is evaluated as true. To evaluate this type of expression, each object in the selection must implement, or adapt to, `org.eclipse.ui.IActionFilter` interface.

- name - the name of an object's attribute. Acceptable names reflect the object type, and should be publicly declared by the plug-in where the object type is declared.
- value - the required value of the object's attribute. The acceptable values for the object's attribute should be publicly declared.

<!ELEMENT pluginState EMPTY>

<!ATTLIST pluginState

id CDATA #REQUIRED

value (installed|activated) "installed">

This element is used to evaluate the state of a plug-in. The state of the plug-in may be one of the following: `installed` or `activated`.

- id - the identifier of a plug-in which may or may not exist in the plug-in registry.
- value - the required state of the plug-in. The state of the plug-in may be one of the following: `installed` or `activated`.

<!ELEMENT systemProperty EMPTY>

<!ATTLIST systemProperty

name CDATA #REQUIRED

value CDATA #REQUIRED>

This element is used to evaluate the state of some system property. The property value is retrieved from the `java.lang.System`.

- name - the name of the system property.
- value - the required value of the system property.

###### Examples:

The following is an example of a view action extension:

       <extension point="org.eclipse.ui.viewActions">
          <viewContribution
             id="com.xyz.xyzViewC1"
             targetID="org.eclipse.ui.views.navigator.ResourceNavigator">
             <menu
                id="com.xyz.xyzMenu"
                label="XYZ Menu"
                path="additions">
                <separator name="group1"/>
             </menu>
             <action
                id="com.xyz.runXYZ"
                label="&amp;Run XYZ Tool"
                menubarPath="com.xyz.xyzMenu/group1"
                toolbarPath="Normal/additions"
                style="toggle"
                state="true"
                icon="icons/runXYZ.gif"
                tooltip="Run XYZ Tool"
                helpContextId="com.xyz.run_action_context"
                class="com.xyz.actions.RunXYZ">
                <selection class="org.eclipse.core.resources.IFile" name="*.java"/>
             </action>
         </viewContribution>
       </extension>

In the example above, the specified action will only enable for a single selection (`enablesFor` attribute). In addition, the object in the selection must be a Java file resource.

The following is an other example of a view action extension:

       <extension point="org.eclipse.ui.viewActions">
          <viewContribution
             id="com.xyz.xyzViewC1"
             targetID="org.eclipse.ui.views.navigator.ResourceNavigator">
             <menu
                id="com.xyz.xyzMenu"
                label="XYZ Menu"
                path="additions">
                <separator name="group1"/>
             </menu>
             <action
                id="com.xyz.runXYZ2"
                label="&amp;Run XYZ2 Tool"
                menubarPath="com.xyz.xyzMenu/group1"
                style="push"
                icon="icons/runXYZ2.gif"
                tooltip="Run XYZ2 Tool"
                helpContextId="com.xyz.run_action_context2"
                class="com.xyz.actions.RunXYZ2">
                <enablement>
                   <and>
                      <objectClass name="org.eclipse.core.resources.IFile"/>
                      <not>
                         <objectState name="extension" value="java"/>
                      </not>
                   </and>
                </enablement>
             </action>
          </viewContribution>
       </extension>

In the example above, the specified action will appear as a menu item. The action is enabled if the selection contains no Java file resources.

###### API Information:

The value of the `class` attribute must be a fully qualified name of a Java class that implements `org.eclipse.ui.IViewActionDelegate`. This class is loaded as late as possible to avoid loading the entire plug-in before it is really needed.

The interface `org.eclipse.ui.IViewActionDelegate` extends `org.eclipse.ui.IActionDelegate` and adds an additional method that allows the delegate to initialize with the view instance it is contributing into.

This extension point can be used to contribute actions into menus previously created by the target view. Omitting the menu path attribute will result in adding the new menu or action at the end of the pulldown menu.

The enablement criteria for an action extension is initially defined by `enablesFor`, and also either `selection` or `enablement`. However, once the action delegate has been instantiated, it may control the action enable state directly within its `selectionChanged` method.

Action and menu labels may contain special characters that encode mnemonics using the following rules:

1. Mnemonics are specified using the ampersand ('&') character in front of a selected character in the translated text. Since ampersand is not allowed in XML strings, use `&amp;` character entity.

If two or more actions are contributed to a menu or toolbar by a single extension the actions will appear in the reverse order of how they are listed in the plugin.xml file. This behavior is admittedly unintuitive. However, it was discovered after the Eclipse Platform API was frozen. Changing the behavior now would break every plug-in which relies upon the existing behavior.

The `selection` and `enablement` elements are mutually exclusive. The `enablement` element can replace the `selection` element using the sub-elements `objectClass` and `objectState`. For example, the following:

     <selection
      class="org.eclipse.core.resources.IFile"
      name="*.java">
     </selection>

can be expressed using:

     <enablement>
      <and>
       <objectClass name="org.eclipse.core.resources.IFile"/>
       <objectState name="extension" value="java"/>
      </and>
     </enablement>

###### Supplied Implementation:

Each view normally comes with a number of standard items on the pulldown menu and local toolbar. Additions from other plug-ins will be appended to the standard complement.

Copyright (c) 2002, 2005 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 http://www.eclipse.org/legal/epl-v10.html